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1
Barman, Gopa. "Synthetic studies on N - Aryl Y - Lactam & N - Aryl Y - Thio - Lactam : chemoselective Transformation to N-Aryl-Pyrrolidine, N-Aryl Succinimide and Other Bioactive Compounds." Thesis, University of North Bengal, 2009. http://hdl.handle.net/123456789/1379.
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Bhattacharya, Biplob. "Synthesis and Anti-MRSA Activity of Hydrophilic C3-Acylated N-Thiolated β-Lactams and N-Acyl Ciprofloxacin-N-Thiolated β-Lactam Hybrids". Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4289.
Full textAbstract:
The Turos laboratory has been working with N-thiolated β-lactams for years trying to understand the mode of action and structural features it needs to have biological activity. Over the years new data has shown promising inhibitory activity against various microbes.
In this dissertation, a review of the vast amount of work carried out on N-thiolated β-lactams in Turos laboratory has been done and their novelty, in terms of structure and mechanism has been discussed. A complete outline of our work in the discovery and ongoing development of these compounds, starting from our initial, unexpected finding of antimicrobial activity for one of the lead compounds, to a more complete understanding of their chemical and biological mode of action and potential utility as antibacterial compounds, has been provided.
Previous researches by graduate students in the Turos laboratory have shown that N-thiolated β-lactams targets Type II Fatty Acid Synthesis (FAS). In process of understanding this further, other FAS inhibiting antibiotics like Triclosan were compared to our lactams by adding excess of exogenous fatty acids. Results revealed vast differences in the MIC value of triclosan and N-thiolated β-lactams, giving an idea that there might be a different mode of action or a different target altogether.
The third chapter discusses the study of attaching hydrophilic C3 side chains like amino acids and carbohydrates on N-thiolated β-lactams while studying the influence of microbiological activity. From the study it was found that the lengthening of the side chain halts the inhibitory activity regardless of whether the side chain contains unsaturation or branching. Results showed that polar groups were not well tolerated and the inhibitory activity goes down regardless of polarity.
Finally, research on dual-action antibiotics was discussed. Antibiotics cause continuous bacterial resistance and in this aspect use of two drugs with different mode of action can call for reduction of the resistance. Herein, N-acyl ciprofloxacin and N-thiolated β-lactams were connected together via an ester linkage. Six new hybrid compounds have been synthesized successfully and tested against E. faecium, K. pneumoniae, A. baumannii, P. aeruginosa, and E. cloacae.
3
Bekdemir, Yunus. "The mechanisms of hydrolysis and protonation behaviour of N-aryl sultams." Thesis, University of Essex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387004.
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Dyke, Alan. "Novel Câ‚‚-symmetric N,N-donor ligands and the anionic thia-Fries rearrangement of aryl triflates." Thesis, University of Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404435.
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Yasui, Hiroto. "Studies on Addition to 1-Aryl-1-alkynes and N-Alkynyl Amides." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/57271.
Full textAbstract:
Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(工学)<br>甲第13827号<br>工博第2931号<br>新制||工||1433(附属図書館)<br>26043<br>UT51-2008-C743<br>京都大学大学院工学研究科材料化学専攻<br>(主査)教授 大嶌 幸一郎, 教授 檜山 爲次郎, 教授 松原 誠二郎<br>学位規則第4条第1項該当
6
Mori, Shigeki. "Studies on metallation of meso-aryl substituted hexaphyrins and N-fused pentaphyrins." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/136922.
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Baeza, Mario Ivan. "Synthesis and characterization of acetylenic derivatives of the actinide extractant (aryl)-N,N-di-(alkyl)carbamoylmethylphosphine oxide (CMPO)." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Prosen, Katherine Rose. "Investigating the Mode of Action of a Novel N-sec-butylthiolated Beta-lactam Against Staphylococcus aureus." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3609.
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N-sec -butylthioloated β-lactam (NsβL) is a novel beta-lactam antimicrobial with a mechanism of action proposed to inhibit 3-oxoacyl-acyl carrier protein synthase (ACP) III (FabH), resulting in the inhibition of fatty acid synthesis. It has been suggested that NsβL inhibits FabH indirectly by inactivating coenzyme-A (CoA). CoA is an essential cofactor for numerous proteins involved in glycolysis, the citric acid cycle (TCA), and pyruvate metabolism, in addition to fatty acid biosynthesis. This study aimed to determine the effects of NsβL on a diverse array of laboratory and clinical Staphylococcus aureus isolates by analyzing the mode of resistance in spontaneous and adaptive mutant NsβL-resistant mutants. Phenotypic analysis of the mutants was performed, as well as sequence analysis of fabH; along with comparative proteomic analysis of intracellular proteomes. Our results indicate that NsβL resistance is mediated by drastic changes in the cell wall, oxidative stress response, virulence regulation, and those pathways associated with CoA. It is our conclusion that Nsβ
L has activity towards CoA, resulting in wide-spread effects on metabolism, virulence factor production, stress response, and antimicrobial resistance.
9
Cui, Xiuhua. "Asymmetric hydrogenations of aryl alkenes using imidazol-2-ylidene iridium complexes." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2456.
Full textAbstract:
A library of iridium complexes featuring oxazoline and imidazol-2-ylidene ligands
were synthesized by reaction of a library of imidazoles with a second library of oxazoline
iodides. These complexes were active catalysts for hydrogenations of aryl substituted
monoenes. Tri- and 1,1-disubstituted alkenes were hydrogenated quantitatively with ee??s
up to 99% at 1 atm hydrogen pressure. Catalyst, substrate, temperature and pressure
effects were studied.
The iridium complexes were also used for the kinetic study of hydrogenation of 2,3-
diphenylbutadiene. This hydrogenation is a stepwise reaction: one double bond was
hydrogenated first, then the second one. Both step hydrogenations were zero order in
alkene. The consumption of 2,3-diphenylbutadiene was first order in catalyst, and
probably first order in hydrogen pressure too. The enantioselectivity for the first step
hydrogenation was low. There were match and mismatch catalyst-substrate relationships
for the second step hydrogenation, and the enantioselectivities for this step were catalyst
controlled. NMR studies indicated that the initiation of the reaction involved both
hydrogen and alkene substrate. A competitive experiment was designed to explore the
formation of meso-alkane at first step hydrogenation, and the results indicated that the
alkane was formed predominantly via an associative mechanism.
Four types of conjugate dienes were synthesized and hydrogenated. Different
reactivities and selectivities were obtained for each type of dienes. In the best case, a
diene was hydrogenated quantitatively with an excellent ent/meso ratio of 20:1.0 and
99% enantioselectivity. The scope, limitation and potential applications of the reactions
were discussed. A selection of the dienes was hydrogenated with the Crabtree??s catalyst,
for comparison, and the yields, conversions and diastereoselectivities were inferior to
those from iridium-oxazoline-imidazol-2-ylidene catalysts.
10
Jiao, Dezhi. "Alkyl and aryl imidazolium salts in aqueous supramolecular systems with cucurbit[n]uril." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610692.
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Zajdel, Pawel. "Novel Aryl-alkyl-piperazines with N-acylated amino acids as serotoninergic receptors ligands." Montpellier 1, 2006. http://www.theses.fr/2006MON13511.
Full textAbstract:
Ce travail présente des nouveaux composés ciblant les récepteurs sérotoninergiques. La première partie traite de la synthèse supposée d'une chimiothèque d'arylpiperazines. Plusieurs composés montrent une haute affinité pour 5-HT1A(K1=3-52nM). Des tests pharmacologiques pré-cliniques ont révélé des comportements de type agoniste complet ou partiel de 5-HT1A ou antagoniste 5-HT1A/5-HT2A. La synthèse supportée de 64 dérivés sulfonamide de la proline carboxamide est décrite, visant l'obtention d'antagonistes de 5-HT7. La dernière partie traite de la synthèse supportée sur lanternes BAL de dérivés d'arylalkyl amines ciblant les récepteurs des amines biogéniques du SNC. Une synthèse originale supportée d'une nouvelle classe d'arylpipérazines a été présentée. L'étude biologique in vitro a révélé plusieurs doubles ligands 5-TH1A/5-HT2A possédant in vivi une activité anxiolytique et antidépressive. Les résultats du criblage des composés sur 5-HT7 aideront à la conception de nouvelles séries.
12
Wang, Yue-Ting. "Detection of reactive intermediates from quinol esters and O-aryl-N-methanesulfonyl hydroxylamine." Miami University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=miami1249001098.
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Mtongana, Sibusiso. "A multinuclear magnetic resonance spectroscopy study of E/Z configurational isomers of unsymmetrical N-alkyl-N-alkyl(aryl)-N'-acylthioureas of platinum(II) complexes." Thesis, Stellenbosch : Stellenbosch University, 2006. http://hdl.handle.net/10019.1/21893.
Full textAbstract:
Dissertation (PhD)--University of Stellenbosch, 2006.<br>ENGLISH ABSTRACT: The partial double bond character of the carbon-nitrogen bond of the (S)C-NRR’ moiety results in unsymmetrical
dialkyl-substituted N-alkyl-N-alkyl(aryl)-N’-acylthioureas, R”C(O)NHC(S)NRR’ (HL) displaying E,Z
configurational isomerism in solution. The isomerism manifests itself by the duplication of resonances of the N-alkyl
groups in the 1H and 13C NMR spectra. In one class of these ligands where R and R’ groups are non-equivalent alkyl
groups the isomerism is easily observable at 298 K in chloroform. In the other class where R’ is still an alkyl group
and R is a para-substituted phenyl group the isomerism is only observable at much lower temperatures due to a lower
barrier to rotation around the (S)C-N(alkyl)(para-X-Ph) bond (X = O-CH3, H and NO2). The electron-withdrawing
nature of the nitro group in N-methyl-N-(4-nitro-phenyl)-N’-2,2-dimethylpropanoylthiourea, HL3A and N-pentyl-N-
(4-nitro-phenyl)-N’-2,2-dimethylpropanoylthiourea, HL3D result in the E,Z isomerism of these ligands not observable
even at 198 K in dichloromethane. The distribution of E and Z isomers of the unbound ligands vary depending on
these R and R’ groups. Several E isomers of these ligands have been isolated and structurally characterised and the
(S)C-NRR’ bond falls in the range [1.343(3) – 1.329(3) Å] which shorter than the average C-N single bond of
1.472(5) Å.
The E,Z configurational isomerism in the unbound ligands is passed on to the Pt(II) chelates derived from these
ligands. The presence of cis-[Pt(ZZ-L-S,O)2], cis-[Pt(EZ-L-S,O)2] and cis-[Pt(EE-L-S,O)2] is readily observable by
means of 195Pt NMR spectroscopy which shows three well resolved resonances, and this can be confirmed by 1H and
13C NMR spectra of these complexes. The 195Pt nuclei are spatially linked to the 13C nuclei, four bonds away
resulting in 4J(195Pt-13C) couplings with N-CH2- or N-CH3 carbons in a W pathway. The 195Pt NMR spectra are also
linked to N-CH2- or N-CH3 proton resonances by means of the ZZ, EZ and EE isomer distributions. Assignment of
these configurational isomers was then achieved by means of a combination of low magnetic field 13C NMR spectra
and high-resolution gHSQC (1H/13C) NMR experiments.
1H NMR rotational dynamics study showed that the barrier to rotation, ΔG≠, around the (S)C-N(Me)(para-X-Ph)
bond in cis-bis(N-methyl-N-(4-methoxy-phenyl)-N’-2,2-dimethylpropanoylthioureato)platinum(II), cis-[Pt(L1AS,
O)2]; cis-bis(N-methyl-N-phenyl-N’-2,2-dimethylpropanoylthioureato)platinum(II), cis-[Pt(L2A-S,O)2] and cisbis(
N-methyl-N-(4-nitro-phenyl)-N’-2,2-dimethylpropanoylthioureato)platinum(II), cis-[Pt(L3A-S,O)2] complexes
was observed to follow the order: (electron-withdrawing group) NO2 < H < (electron-donating group) O-CH3. The
ZZ isomer was observed to be favoured over the EZ and EE isomers in this order of the para-substituent on the Nphenyl
group. The 1H dynamic NMR trends about the barrier to rotation, ΔG≠, around the (S)C-N(Me)(para-X-Ph)
bond were also complemented by DFT linear transit calculations. The isomer distributions were also influenced by
solvent polarity and the temperature at which the distributions are determined apart from the electronic influence of
the para-substituent of the N-phenyl group.
The ZZ, EZ and EE isomers of complexes derived from N-alkyl-N-(para-X-Ph)-N’-acylthioureas with varying Nalkyl
substituent (methyl, isopropyl, cyclohexyl and n-pentyl) were determined from the 195Pt NMR spectra which were measured under identical conditions. The ZZ isomer was observed to be favoured over the EZ and EE isomers
upon methyl group substitution with a bulkier alkyl group in the order: methyl < isopropyl < cyclohexyl < n-pentyl.
Qualitatively it has been shown that a bulkier N-pentyl group increases the barrier to rotation around the (S)CN(
alkyl)(para-X-Ph) bond over the N-methyl group and this leads to higher concentrations of the ZZ isomer over the
EZ and EE isomers. The combined effects of the electron-donating substituent (X = O-CH3) on the N-(para-X-Ph)
group and the bulkier N-alkyl group (n-pentyl) result in highest ZZ concentration (76 %) over EZ and EE isomers in
the complex cis-bis(N-pentyl-N-(4-methoxy-phenyl)-N’-2,2-dimethylpropanoylthioureato)platinum(II), cis-[Pt(L1DS,
O)2]. The lowest concentration ZZ (27 %) is obtained in the complex cis-bis(N-methyl-N-(4-nitro-phenyl)-N’-2,2-
dimethylpropanoylthioureato)platinum(II), cis-[Pt(L3A-S,O)2] when the coordinated ligand has both N-methyl group
and N-(4-nitro-Ph) group which both lower the barrier to rotation around the (S)C-N(alkyl)(para-X-Ph) bond.
A crystal of the complex cis-bis(N-pentyl-N-(4-methoxy-phenyl)-N’-2,2-dimethylpropanoylthioureato)platinum(II),
cis-[Pt(L1D-S,O)2] has been isolated and structurally characterised and was shown to be in the ZZ configuration,
which is the major component (76 %) in chloroform. This is the first example of Pt(II) chelates with asymmetrically
disubstituted ligands to be reported.<br>AFRIKAANSE OPSOMMING: Die gedeeltelike dubbelbinding karakter van die koolstof-stikstof-binding van die (S)C-NRR’-moieteit lei tot
onsimmetriese dialkiel-gesubstitueerde N,N-dialkiel-N’-asieltioureums, R”C(O)NHC(S)NRR’ (HL) wat E,Zkonfigurasionele
isomerie in oplossing besit. Die isomerie is sigbaar in die verdubbelling van die seine van die Nalkielgroepe
in die 1H- en 13C-KMR spektra. In een so klas ligande waar R- en R’-groepe nie-ekwivalente
alkielgroepe is, is isomerie duidelik sigbaar by 298 K in chloroform. In die ander klas waar R’ steeds ’n alkielgroep
is, en R ’n para-gesubstitueerde feniel groep, is die isomerie alleenlik sigbaar by baie laer temperature as gevolg van
’n laer rotasieversperring om die (S)C-N(alkiel)(para-X-Ph)-binding (X = O-CH3, H and NO2). Die
elektrononttrekkende aard van die nitrogroep in N-metiel-N-(4-nitrofeniel)-N’-(2,2-dimetielpropanoïel)tioüreum,
HL3A en N-(4-nitrofenyl)-N-pentiel-N’-(2,2-dimetielpropanoïel)tioüreum, HL3D lei daartoe dat die E,Z-isomerie van
die ligande nie eers by 198 K in dichlorometaan waargeneem word nie. Die verspreiding van die E en Z isomere
verskil na gelang van die R en R’ groepe. Verskeie E-isomere van hierdie ligande is geïsoleer en struktureel
gekarakteriseer en die (S)C-NRR’-bindingslengte is in ‘n gebied [1.343(3) – 1.329(3) Å] wat korter is as die
gemiddelde C-N-enkelbindingslengte van 1.472(5) Å.
Die Pt(II) chelate wat afgelei is van die ligande is blootgestel aan die E,Z-konfigurasie isomere van die ongebinde
ligande. Die teenwoordigheid van cis-[Pt(ZZ-L-S,O)2], cis-[Pt(EZ-L-S,O)2] en cis-[Pt(EE-L-S,O)2] is maklik
waarneembaar deur middel van 195Pt-KMR-spektroskopy wat drie goed geresolueerde seine toon, en dit kan bevestig
word met 1H- en 13C-KMR spectra van hierdie komplekse. Die 195Pt kerne is ruimtelik geskakel met die 13C kerne
deur vier bindings wat aanleiding gee tot 4J(195Pt-13C)-koppelings met N-CH2- of N-CH3-koolstofatome in ‘n Wkonformasie.
Die 195Pt KMR spektra word geskakel met die N-CH2- of N-CH3-protonresonansies in al drie die
moontlike ZZ, EZ en EE kompleksisomere. Toekenning van die konfigurasionele isomere is dan bewerkstellig deur
middel van ‘n kombinasie van lae magneetveld 13C-KMR spectra en hoë resolusie gHSQC (1H/13C) KMR
experimente.
1H-KMR-rotasiedinamiek studie toon dat die rotasiegrens, ΔG≠, om die (S)C-N(Me)(para-X-Ph)-binding in cisbis(
N-metiel-N-(4-metoksifeniel)-N’-2,2-dimetielpropanoïeltioureato)platinum(II), cis-[Pt(L1A-S,O)2]; cis-bis(Nfeniel-
N-metiel-N’-2,2-dimetielpropanoïeltioureato)platinum(II), cis-[Pt(L2A-S,O)2] en cis-bis(N-metiel-N-(4-
nitrofeniel)-N’-2,2-dimetielpropanoïeltioureato)platinum(II), cis-[Pt(L3A-S,O)2] komplekse was met die volgende
orde bepaal: (elektron-ontrekkende groep) NO2 < H < (elektron-skenkende groep) O-CH3. Die ZZ-isomeer blyk by
voorkeur te vorm bo die EZ- en EE-isomere in dieselfde orde as hierbo wat betref para-substituent aan die Nfenielgroep.
Die 1H dinamiese KMR tendencies ten opsigte van die rotasiegrens, ΔG≠, om die (S)C-N(Me)(para-XPh)-
binding is gekomplimenteer met DFT-linêre organgs berekeninge. Die isomer verspreidings blyk ook beïnvloed
te word deur die oplosmiddel polariteit en die temperatuur waarby die verspreidings bepaal is, buiten die elektroniese
invloed van die para-substituent aan die N-fenielgroep. Die ZZ, EZ en EE isomeer verspreiding van komplekse wat afgelei is van N-alkiel-N-(para-X-Ph)-N’-asieltioureums
met veranderlike N-alkiel substituente (metiel, isopropyl, sikloheksiel, en n-pentiel) is vasgestel deur middel van die
195Pt KMR wat opgeneem is onder identiese kondisies. Die ZZ-isomeer blyk die verkose isomeer te wees bo die EZen
EE-isomere waar die metiel substituent vervang word met ‘n groter alkiel groep in die orde van: metiel <
isopropiel < sikloheksiel < n-pentiel. Dit is kwalitatief getoon dat die groter N-pentielgroep die rotasiegrens verhoog
vir rotasie om die (S)C-N(alkiel)(para-X-Ph)-binding bo dié van die N-metielgroep wat aanleiding gee tot hoër
konsentrasies van die ZZ-isomeer relatief tot die EZ- en EE-isomere. Die gekombineerde uitwerking van die
electron-skenkende substituent (O-CH3) op die N-(para-X-Ph)-groep en die groter N-alkiel groep (n-pentiel) gee
aanleiding tot die hoogste ZZ-konsentrasie (76%) bo EZ- en EE-isomere in die kompleks cis-bis(N-pentiel-N-(4-
metoksifeniel)-N’-2,2-dimetielpropanoïeltioureato)platinum(II), cis-[Pt(L1D-S,O)2]. Die laagste konsentrasie ZZ
(27%) is verkry in die kompleks cis-bis(N-metiel-N-(4-nitrofeniel)-N’-2,2-dimetielpropanoïel)tioureato)platinum(II),
cis-[Pt(L3A-S,O)2] waar die gekoördineerde ligand beide die N-metiel- sowel as die N-(4-nitro-Ph)-groep, wat albei
die rotasiegrens van die (S)C-N(alkiel)(para-X-Ph)-binding verlaag.
‘n Kristalstruktuur van die kompleks cis-bis(N-pentiel-N-(4-metoksifeniel)-N’-2,2-dimetielpropanoïeltioureato)
platinum(II), cis-[Pt(L1D-S,O)2] wat geïsoleer is, is struktureel gekarakteriseer en is in die ZZ-konfigurasie,
wat die hoofkomponent (76%) is in chloroform. Hierdie is die eerste voorbeeld van Pt(II) chelate met asimmetriese
digesubstitueerde ligande om geraporteer te word.
14
Bruce, Jocelyn Catherine. "Use of the N,N-dialkyl-N’-benzoyl(thio)selenoureas as single source precursors for the synthesis of semiconducting quantum dots." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/1205.
Full textAbstract:
Thesis (PhD (Chemistry and Polymer Science))--Stellenbosch University, 2008.<br>The successful preparation and structural characterization of a number of N,N-dialkyl-N’-benzoyl(thio)selenourea
ligands is described; where the intermolecular interactions are characterized by the presence of Resonance Assisted
Hydrogen Bonding (RAHB), π- π interactions between neighbouring benzene residues only being evident amongst
the longer alkyl chain derivatives. The first structural characterization of an asymmetrically substituted N,N-dialkyl-
N’-benzoylselenourea ligand reveals an increased stability of the Z isomer in the solid state, this being reflected by
the sulfur analogue. Attempts to synthesise N,N-dicyclohexyl-N’-benzoylselenourea led to the isolation and
structural characterization of a novel 1,3,5-oxaselenazine salt and dicyclohexylaminobenzoate. The first structural
characterization of a “bipodal” N,N-dialkyl-N’-benzoylselenourea ligand, 3,3,3’,3’-tetrabutyl-1,1’-
isophthaloylbis(selenourea), reveals RAHB in the crystal lattice similar to that exhibited by the “monopodal”
analogue, N,N-dibutyl-N’-benzoylselenourea.
The successful complexation of the N,N-dialkyl-N’-benzoyl(thio)selenourea ligands to a number of different
transition metal ions is reported allowing the preparation of several potential single source precursors. Coordination
through the O and Se/S donor atoms to Pd(II) results in the formation of square planar metal complexes, with a cis
conformation, several of which could be structurally characterized. In particular, the first structural elucidation of an
asymmetrically substituted N,N-dialkyl-N’-benzoylselenourea metal complex, cis-bis(N-benzyl-N-methyl-N’-
benzoylselenoureato)palladium(II) indicates the increased stability of the EZ isomer in the solid state. Structural
elucidation of the novel (N,N-diphenyl-N’-benzoylselenoureato)cadmium(II) reveals a bimetallic complex in the
solid state, where the expected 2:1 ligand : metal ratio is maintained, and the two Cd(II) centres are 5 and 6
coordinated, with O and Se donor atoms. Multinuclear Nuclear Magnetic Resonance (NMR) Spectroscopy has been
employed in the thorough characterisation of the potential single source precursors, 77Se NMR spectroscopy
indicating a decreased shielding of the 77Se nucleus as the “hardness” of the central metal ion increases i.e. Pd(II) >
Zn(II) > Cd(II). Use of 113Cd NMR spectroscopy indicates the preferential binding of N,N-diethyl-N’-
benzoylselenourea to Cd(II) over that of its sulfur analogue, and initial studies suggest a form of chelate metathesis
taking place in solution. 31P NMR spectroscopy is used to gain insight into the formation of cis-bis(N,N-diethyl-N’-
benzoylselenoureato)Pt(II).
Thermolysis of (N,N-diethyl-N’-benzoylselenoureato)cadmium(II) and its sulfur analogue led to the successful
synthesis of CdSe and CdS quantum dots respectively, where thermolysis over a range of temperatures allows a
degree of size control over the resulting nanoparticles. The effect of precursor alkyl chain length on nanoparticle
morphology was investigated for both the N,N-dialkyl-N’-benzoylthio- and –selenoureas. A correlation between the
two for the (N,N-dialkyl-N’-benzoylselenoureato)Cd(II) complexes is described and possible growth mechanisms
are discussed. Preliminary investigations into the use of other N,N-dialkyl-N’-benzoyl(thio)selenourea metal
complexes as single source precursors reveal that both (N,N-diethyl-N’-benzoylselenoureato)Zn(II) and its sulfur
analogue show potential as single source precursors for the formation of ZnO and ZnS nanoparticles respectively.
Initial studies into the use of N,N-dialkyl-N’-benzoyl(thio)selenourea metal complexes as single source precursors
for the synthesis of core-shell nanoparticles is briefly described.
The Aerosol Assisted Chemical Vapour Deposition (AACVD) of several N,N-dialkyl-N’-benzoyl(thio)selenourea
metal complexes is reported, where both (N,N-diethyl-N’-benzoylselenoureato)Cd(II) and its sulfur analogue allow
the deposition of crystalline CdSe and CdS respectively. The AACVD of (N,N-diethyl-N’-
benzoylselenoureato)Zn(II) leads to the deposition of crystalline ZnSe, ZnS being deposited by (N,N-diethyl-N’-benzoylthioureato)Zn(II). The deposition of heazelwoodite (Ni3S2) with varying morphologies results from the
AACVD of cis-bis(N,N-diethyl-N’-benzoylthioureato)Ni(II). Thermal annealing of the amorphous material
deposited by the AACVD of cis-bis(N,N-diethyl-N’-benzoylthioureato)Pd(II), allows the formation of highly
crystalline palladium. The deposition of metallic platinum using cis-bis(N,N-diethyl-N’-benzoylthioureato)Pt(II) is
described as well as the deposition of crystalline Pd17Se15 from cis-bis(N,N-diethyl-N’-benzoylselenoureato)Pd(II).
This, to the best of our knowledge, is the first time that AACVD has been performed, using the N,N-dialkyl-N’-
benzoyl(thio)selenourea metal complexes as single source precursors, in addition, we believe it to be the first time
that palladium selenide has been deposited using the AACVD technique.
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Axelsson, Linda. "Development of HIV-1 Protease Inhibitors and Palladium-Catalyzed Synthesis of Aryl Ketones and N-Allylbenzamides." Doctoral thesis, Uppsala universitet, Institutionen för läkemedelskemi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-211672.
Full textAbstract:
The use of palladium-catalyzed reactions to introduce new carbon-carbon bonds is a fundamental synthetic strategy that has been widely embraced due to its high chemo- and regioselectivity and functional group tolerance. In this context, Pd(0)-catalyzed aminocarbonylations using Mo(CO)6 instead of toxic and gaseous CO and with allylamine as the nucleophile were investigated. The aminocarbonylated product dominated over the Mizoroki-Heck product, and (hetero)aryl iodides, bromides and chlorides gave N-allylbenzamides in good yields. In this thesis improvements to an existing protocol for the Pd(II)-catalyzed synthesis of aryl ketones from five benzoic acids and a variety of nitriles are also presented. Addition of TFA improved the yields and employing THF as solvent enabled the use of solid nitriles, and the aryl ketones were isolated in good yields. The pandemic of HIV infection is one of the greatest public health issues of our time and approximately 35.3 million people worldwide are living with HIV. There are currently many drugs on the market targeting various parts of the viral reproduction cycle, but the problems of resistance warrant the search for new drugs. HIV-1 protease makes the virus mature into infectious particles. In this thesis a new type of HIV-1 protease inhibitor (PI) is presented, based on two of the PIs on the market, atazanavir and indinavir, but it has a tertiary alcohol, as well as a two-carbon tether between the quaternary carbon and the hydrazide β-nitrogen. A total of 25 new inhibitors were designed, synthesized and biologically evaluated, the best compound had an EC50 value of 3 nM. Based on this series a project aimed at synthesizing macrocycles spanning the P1-P3 area was initiated. Macrocycles often tend to have an improved affinity and metabolic profile compared to their linear analogs. Introduction of a handle in the para position of the P1 benzyl group proved difficult, despite efforts to synthesize intermediates containing either a bromo-, hydroxy-, methoxy-, silyl-group protected hydroxy- or an alkyne-group. The lactone intermediate was abandoned in favor of an alternative synthetic route and initial studies were found to be promising. This new approach requires further investigation before the target macrocycles can be synthesized.
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El-Hassan, Inas. "Synthèse de N-aryl-C, C-dialkoxycarbonylnitrones et étude par RPE de leur conversion en nitroxydes." Aix-Marseille 1, 2006. http://www.theses.fr/2006AIX11033.
Full textAbstract:
La première partie de ce mémoire décrit la synthèse d'une série de sept N-Aryl-C,C-dialkoxycarbonylnitrones (1-7), par condensation d'un carbanion dérivé du bromomalonate d'éthyle ou de méthyle sur un composé nitroso approprié. Les rendements en cétonitrones varient de 25 % à 85 %, en fonction de la nature du groupement aryle. La seconde partie concerne la conversion des cétonitrones 1-7 en nitroxydes selon trois mécanismes : le piégeage de radicaux, la réaction de Forrester-hepburn et le piégeage de SPIN inversé. Ces cétonitrones sont toutes de très bons pièges des radicaux carbones, mais sont inadaptées à la détection des radicaux hydroxyle et superoxyde. Lorsqu'elles ont été mises en oeuvre dans des réactions de Forrester-Hepburn avec toute une série d'agents nucléophiles, seuls quelques uns des nitroxydes attendus ont effectivement été détectés, et dans la majorité de cas un produit de décomposition paramagnétique a été observé. Le mécanisme de piégeage de SPIN inversé n'a été utilisé que pour convertir les cétonitrones en bitroxydes des BETA-FLUORES. Cinq de ces sept nitrones étudiées ont permis de réaliser cette conversion. Tous les nitroxydes dérivés des cétonitrones 1-7, quel que soit leur mécanisme de formation, ont été caractérisés par leur spectre de résonance paramagnétique électronique (RPE). Les signaux obtenus consistent principalement en un triplet, dû au couplage hyperfin entre l'électron non apparié et l'azote de la fonction aminoxyle, élargi ou démultiplié du fait de couplages hyperfins avec les protons du cycle aryle. Des signaux plus simples ont été obtenus à partir de nitrones portant des groupements substituants ou des deutériums sur le cycle aromatique
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Chopra, Karishma. "Improved Cryopreservation of Induced Pluripotent Stem Cells Using N-aryl Glycosidic Small Molecule Ice Recrystallization Inhibitors." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42323.
Full textAbstract:
Induced pluripotent stem cells (iPSCs) are an attractive cell source for various applications in regenerative medicine and cell-based therapies given their unique capability to differentiate into any cell type of the human body. However, human iPSCs are highly vulnerable to cryopreservation with post-thaw survival rates of 40-60%; this is due to cryoinjury resulting from ice recrystallization when using conventional slow cooling protocols.
Ice recrystallization is a process where the growth of large ice crystals occurs at the expense of small ice crystals. Ice recrystallization inhibitors (IRIs) are designed to inhibit the growth of intracellular ice crystals, increasing post-thaw viability. In this study, we tested a panel of four IRIs to determine if the inhibition of ice recrystallization can decrease cellular damage during freezing and improve viability post-thaw of iPSC colonies. We supplemented commercially available and serum-free cryopreservation medium mFreSR, routinely used for the cryopreservation of iPSCs, with a class of N-aryl-D-ß-gluconamide IRIs. A 2-fold increase in post-thaw viability was observed, in a dose dependent response, for N-(4-methoxyphenyl)-D-gluconamide (PMA) at 15 mM, N-(2-fluorophenyl)-D-gluconamide (2FA) at 10 mM, and N-(4-chlorophenyl)-D-gluconamide (4ClA) at 0.5 mM over mFreSR controls. After testing the panel of four IRIs, 2FA frozen iPSCs showed an increase in cell viability, proliferation, and recovery. The addition of ROCK inhibitor (RI), commonly used to increase iPSC viability post thaw, further enhanced the survival of the iPSCs frozen in the presence of 2FA and is used routinely in research. This additive effect increased cell recovery and colony formation post thaw, resulting in increased proliferation with no adverse effects on iPSC pluripotency or differentiation capabilities.
The development of improved cryopreservation strategies for iPSCs is key to establishing master clonal cell banks and limiting cell selection pressures, all while maintaining high post-thaw viability and function. This will help ensure sufficient supplies of high-quality iPSC required to meet the cell demands for cell and regenerative based therapies. Since iPSCs hold promise as a potentially unlimited cell source for a plethora of cell-based therapies, improving cryopreservation is essential to the successful deployment of iPSC-derived therapeutic cell products in the future.
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Delgado, Justine Lane. "Design, synthesis, and evaluation of N-1 Aryl fluoroquinolones for the development of human topoisomerase inhibitors." Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6564.
Full textAbstract:
DNA topoisomerases are responsible for managing the topology of DNA and play critical roles in many biological processes involving DNA. DNA topoisomerases are known therapeutic targets of several successful anticancer chemotherapeutics. Most clinically used topoisomerase-targeting anticancer drugs convert the enzyme into a cellular poison by trapping a covalent topoisomerase-DNA catalytic intermediate as a topoisomerase-drug-DNA ternary complex. Formation of ternary complex leads to cytotoxic events, such as inhibition of DNA replication, DNA strand breaks, and ultimately cell death. This mode of action is associated with the development of secondary leukemias and cardiotoxicity.
Two lead molecules were discovered that catalytically inhibit human topoisomerase I and II. The lead molecules guiding this work do not act as topoisomerase poisons, which may eliminate some of the severe side effects associated with current topoisomerase-targeting agents. These lead molecules were found to exhibit anti-proliferative activity against several cancer cell lines in cell culture and against colon cancer in an animal model. Thus, these novel small molecules or their structural derivatives with improved human topoisomerase I inhibitory activity and biophysical properties, may be developed as novel anticancer therapeutics.
An important objective of this work was to explore structural requirements required for inhibition of human topoisomerases I and II. To achieve this objective, functional group modifications to the N-1, C-3, C-6, C-7, and C-8 positions of the quinolone core were explored to gain an understanding of structural requirements for inhibition of human topoisomerases while striving to improve potency and biophysical properties.
In addition to exploration of structural requirements for human topoisomerase inhibition, the in vitro anti-proliferative activity of novel fluoroquinolone analogs identified was determined. As fluoroquinolones are known to partially intercalate DNA, the role of N-1 aryl fluoroquinolone-DNA binding in anti-proliferative activity and human topoisomerase I inhibition was also evaluated.
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Aquino, Estefania da Costa. "Síntese de 3-Trifluoracetil-1H-pirróis N-Aril Substituídos." Universidade Federal de Santa Maria, 2011. http://repositorio.ufsm.br/handle/1/10481.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico<br>This work presents a new, simple and versatile strategy for the synthesis of new N-aryl substituted 3-trifluoroacetyl-1H-pyrroles. The pyrroles were obtained by the reaction of 3-trifluoroacetyl-4,5-dihydrofuran with aryl amines of general formula ArNH2, and Ar= C6H4, 2-MeO(C6H4), 3-MeO(C6H4), 4-MeO(C6H4), 2-Me(C6H4), 3-Me(C6H4), 4-Me(C6H4), 3-F(C6H4), 4-F(C6H4), 3-Cl(C6H4), 4-Cl(C6H4), 4-OH(C6H4), 2-OH-5-Me(C6H3), 3-OH-4-Me(C6H3), 4-Br(C6H4) generating 1,1,1-trifluoro-3-(2-hydroxyethyl)-4-arylamino-3-beten-2-ones intermediates that could not be isolated. These intermediaries were submitted to Swern oxidation reaction producing 1,1,1-trifluoro-3-(2-ethanal)-4-arylamino-3-buten-2-ones that underwent intramolecular cyclization followed by aromatization by dehydratation, producing N-aryl substituted 3-trifluoracetyl-1H-pyrroles in 30-56% yield. The pyrroles obtained in this study were identified by 1H NMR, 13C NMR, and GC-Mass Espectroscopy.<br>Este trabalho apresenta uma nova estratégia sintética simples e versátil para a preparação de uma série inédita de 3-trifluoracetil-1H-pirróis N-aril substituídos. Os pirróis foram obtidos a partir da reação do 3-trifluoracetil-4,5-diidrofurano com aril aminas de fórmula geral ArNH2, sendo Ar= C6H4, 2-MeO(C6H4), 3-MeO(C6H4), 4-MeO(C6H4), 2-Me(C6H4), 3-Me(C6H4), 4-Me(C6H4), 3-F(C6H4), 4-F(C6H4), 3-Cl(C6H4), 4-Cl(C6H4), 4-OH(C6H4), 2-OH-5-Me(C6H3), 3-OH-4-Me(C6H3), 4-Br(C6H4) gerando os intermediários 1,1,1-trifluoro-3-(2-hidroxietil)-4-arilamino-3-buten-2-onas, que não foram isolados. Esses intermediários foram submetidos a reação de oxidação de Swern produzindo 1,1,1-trifluoro-3-(2-etanal)-4-arilamino-3-buten-2-onas que sofreram reação de ciclização intramolecular, seguido de aromatização com a perda de uma molécula de água produzindo os 3-trifluoracetil-1H-pirróis N-aril substituídos, com rendimentos reacionais (30-56%). Os pirróis obtidos neste trabalho foram identificados por Ressonância Magnética Nuclear de Hidrogênio, Ressonância Magnética Nuclear de Carbono-13 e Espectroscopia de Massas.
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Esposito, Oriana. "Mechanistic and kinetic studies on aryl and alkyl amination reaction catalysed by palladium n-heterocyclic carbene complexes." Thesis, University of Sussex, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487117.
Full textAbstract:
Several studies have been carried out to establish the sequence of intermediates in the catalytic cycle for amination of aryl halides. I ,2 The mechanism suggested by Cloke and Caddick group for the catalytic amination of aryl chloride employing [Pd(NRC)2l as precatalyst (NRC = ·N-heterocyclic carbene), proposed a neutral, 12-electrons mono-ligated Pd(NHC) species as the active intermediate.3 The isolation of a series of (ItBu)2Pd(R-aryl)chloride complexes (ltBu = 1,3-di-tert-butylimidazol-2-ylidene) allowed for kinetic studies hence leading to a mechanistic understanding of the I oxidative addition step, confirming that it occurs by a dissociative mechanism. The subsequent step in the amination catalytic cycle, namely, the dissociation of a carbene and coordination of an amine was investigated and the results are presented in this thesis, and an array of (ItBu)Pd(amine)(R-aryl)chloride complexes were isolated and fully characterized. Kinetic studies were undertaken in order to identify the rate determinig step of the transamination reaction. Moreover, the electronic properties of the para-substituents (R) on the aryl groups of the (ItBu)2Pd(R-aryl)chloride complexes were found not only to influence the rate of the oxidative addition reaction, but also to affect the carbene displacement by the amines. Parallel research based on the understanding of the mechanism of oxidative addition of alkyl halides to the Pd(NHC)2 species have been undertaken, and the synthesis of (ItBu)Pd(neopentyl)chloride (trans isomer) and (IPr)Pd(neopentyl)chloride (cis isomer) (IPr = 1,3-Bis(2,6-Diisopropylphenyl)imidazol-2-ylidene) were. accomplished. Reactivity of these· two complexes was tested toward amines, revealing the significant influence ofN-substituents on the stability of the resulting compounds, and highlighting a possible barrier concerning the achievement of a Pd-catalysed alkyl amination reaction. The oxidative addition of (trimethylsilyl)methyl iodide to Pd(ItBu)z complex was investigated for comparison to the oxidative addition reactions of alkyl halides to the same palladium complex. The unexpected resultant complex, Pd(CHzltBu)zlz, was subjected to DFT study by Dr. Hazari to confirm the zwitterionic nature of the ligand. Kinetic study was conducted on the oxidative addition of TMSI to Pd(ItBu)z to reveal the occurrence of pre-dissociation of one ligand before the addition ofTMSI to yield the [(ItBu)Pd(TMS)(J.t-I)]z.
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Ng, Fei-yeung, and 吳飛洋. "Structure and properties of self-assembled coordination compounds: homoleptic d10-metal aryl/alkylacetylides, ruthenium n-heterocyclesand picolinates." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37878566.
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Mayoka, Godfrey Wabwile. "Synthesis, pharmacological and physicochemical profiling of antimalarial and antischistosomal N-aryl 3-trifluoromethyl pyrido [1,2-α] benzimidazoles". Doctoral thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29825.
Full textAbstract:
Malaria and schistosomiasis represent the two most prevalent parasitic infections with grievous repercussions on the socio-economic development of affected countries, mainly in sub-Saharan Africa and South-East Asia. Despite their ravaging effects, the treatments of these two diseases have been committed to a limited arsenal of drugs that are threatened by resistance. This scenario, therefore, calls for decisive steps being taken towards the discovery and development of novel drugs with the ability to target multiple parasite stages and be efficacious against resistant parasite strains to achieve effective control and treatment of malaria and schistosomiasis. Originating from a World Health Organisation-Tropical Disease Research initiative, a phenotypic whole cell screening was conducted on a commercial library against Plasmodium falciparum whereupon novel hits exemplified by compound 1, embodying a pyridobenzimidazole (PBI) scaffold, were found to portray in vitro potency against both chloroquine sensitive and resistant parasites. Initial medicinal chemistry iterations generated analogues including 2 from which improved in vitro potency and demonstrable in vivo efficacy in a mouse model were observed. In this thesis, further structural diversity around the PBI motif 3 (Figure 1) was pursued with the aim of generating analogues for structure-activity and structure-property relationship studies. Beyond the asexual blood stage activity, the library of compounds generated was also evaluated for activity against the liver and gametocyte stages of Plasmodium. In exploring the probable mechanism of antimalarial action based on their planar morphology and existence of basic centres, the compounds were evaluated for their capacity to disrupt the heme detoxification process, a recognised druggable target in antimalarial drug discovery. Prioritised compounds, based on in vitro potency, were progressed for in vitro drug metabolism and pharmacokinetics assessment, including metabolic stability and cytotoxicity against Chinese hamster ovarian cell lines. Representative compounds were evaluated for their interaction potential with the human ether-a-go-go-related gene (hERG), a potassium ion channel whose inhibition can cause potentially fatal irregular heartbeats due to perturbed repolarisation of the myocardial action potential. In vivo proof-of-concept efficacy and pharmacokinetics studies were carried out on the most promising leads according to a predetermined screening cascade. Arising from this work, structure-activity relationship (SAR) trends were discernible with electron withdrawing substituents on the aromatic side appendage providing active analogues compared to compounds comprising hydrophilic electron-releasing or donating substituents. Following in vitro microsomal metabolic stability analysis, the series displayed moderate to good metabolic stability with compounds incorporating heteroaromatic side groups showing increased susceptibility to biotransformation usually arising from the aromatic ring. In a P. berghei mouse model at an oral dose of 50mg/kg over four consecutive days, two compounds 1j/GMP-19 and 4i/GMP-75 achieved 98% and 99.9% reduction in parasitaemia and led to mean survival days of 12 and 14, respectively, compared to the untreated infected mice which survived for only 6 days. A drug repositioning approach was pursued, exploiting the cellular and biological similarities in the haemoglobin degradation pathways existent in both Plasmodium parasites and schistosomes. Out of the 57 analogues tested, 12 were found to be potent inhibitors of the adult worms (IC50 ≤ 2 µM), with several compounds also displaying potency against the newly transformed schistosomula. Structural features consistent with good antischistosomal potency, interestingly, overlapped with those present in some compounds that also showed good antiplasmodial activity. Prioritised compounds subjected to in vivo efficacy studies in mice infected with schistosomes identified 1b/GMP-09, 1j/GMP-19 and 4i/GMP-75 with modest antischistosomal activity (55- 70% total worm reduction). Metabolic stability and physicochemical properties correlated with observed in vivo efficacy and solubility- limited absorption was implicated to contribute to low in vivo exposure of the compounds. Further profiling of physicochemical parameters revealed the interdependence of the properties and that crystallinity, as measured by the melting point, influenced compound solubility. In summary, the work pursued in this thesis has unravelled the structural features compatible with potent antimalarial and antischistosomal activities of N-aryl substituted 3- trifluoromethyl PBI derivatives. Additionally, structure-property trends of generated analogues have been delineated. The evolvable nature of the structure-activity and structureproperty relationship trends make these compounds appealing as candidates for further optimisation campaigns to impart improvements in physicochemical properties and drug metabolism and pharmacokinetics attributes without abrogating activity. Moreover, having identified the overlap as well as divergence in chemical spaces relating to antimalarial and antischistosomal potencies of these series inspire further investigations into the mechanisms of observed antiparasitic actions. Finally, that this work has identified targets which are panactive across multiple stages of both Plasmodium and schistosomes, and possessing favourable safety profiles, provide an exciting opportunity for pursuing these analogues as antimalarial and antischistosomal leads with the potential for malaria chemoprevention and transmission blocking.
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Hartsel, Joshua Alan. "Revisiting aryl N-methylcarbamate acetylcholinesterase inhibitors as potential insecticides to combat the malaria-transmitting mosquito, Anopheles gambiae." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/73002.
Full textAbstract:
My graduate work focused on the syntheses and pharmacology of species-selective aryl methylcarbamate acetylcholinesterase inhibitors to combat the malaria-transmitting mosquito, Anopheles gambiae. We identified six novel carbamates that demonstrated levels of target selectivity exceeding our project milestone of 100-fold. Among the C2-substituted phenylcarbamates examined (class II), 2'-(2-
ethylbutoxy)phenyl N-methylcarbamate (9bd*) was extraordinarily selective (570-fold + 72). The high level of selectivity observed for many of the class II carbamates was attributed to a helical displacement within the active site of An. gambiae
acetylcholinesterase, able to accommodate carbamates with larger C2-substituted secondary β-branching side chains. Conversely, this type of side chain forms unfavorable interactions within the active site of human acetylcholinesterase. The C3-substituted carbamates (class I), such as terbam (9c), were less selective than many of the class II carbamates; however, class I carbamates related to terbam (9c) were highly toxic to An.
gambiae. In particular, the contact toxicity measured for 9c (LC50 = 0.037 mg/mL) was equal to the commonly used agricultural insecticide, propoxur (9a, LC 50 = 0.037 mg/mL). In total, seventy aryl carbamates were screened for their inhibition potency and contact toxicity towards An. gambiae.
The common final step in all of these syntheses was the carbamoylation of a phenol, which normally proceeded in a 70 to 90% yield. Thirty seven novel carbamates are reported out of the seventy two prepared. Although sixteen of the phenols were
commercially available, the others were prepared with known and adapted synthetic methodologies. The emerging structure-activity relationships led us to focus on the synthesis of 3-tert-alkylphenols (Class I) and 2-alkoxy or 2-alkylthio-substituted phenols (Class II). Three methods particularly stand out: First, we applied the methods of Tanaka to prepare 3-tert-alkylphenols wherein a methyl group was replaced by a trifluoromethyl group. Second, we adapted the methods of Tanaka to prepare 3-tert-alkylphenols that lack fluorine substitution. This method is competitive with the little known method of
Reetz to convert aryl ketones to the corresponding 1,1-dimethylalkyl group and allows one to access electron rich tert-alkyl-substituted aromatics that are not accessible by the Friedel-Crafts alkylation (Friedel-Crafts restricted). Third, we found a convenient and high-yielding method for selective S-alkylation of 2-mercaptophenol. In addition to the synthesis of carbamates, the preparation of one hundred three intermediates, phenols, and electron rich tert-alkyl arenes are reported.<br>Ph. D.
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Odabas, Serhat. "Asymmetric Synthesis Of N-aryl Substituted Chiral 1,4-amino Alcohol Derivatives And Applications In Various Asymmetric Transformation Reactions." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608489/index.pdf.
Full textAbstract:
The asymmetric synthesis of N-aryl substituted chiral 1,4-aminoalcohols and their applications in asymmetric borane reduction and enantioselective diethylzinc addition to benzaldehyde reactions were performed starting from meso anhydride 51 that is the cycloadduct of cyclopentadiene and maleic anhydride. The desymmetrization of meso-anhydride 51 was achieved by using quinine or quinidine with very high enantiomeric excess value (up to 98% ee) and with high chemicalb yield. The quinine-mediated desymmetrization of meso-anhydride 51 with methanol gave (2S,3R)-(-)-cis-monoester 52. The hemiester was subjected to chemoselective amidation with various types of N-aryl substituted amines and then, it was treated with LAH and followed by hydrogenation in the presence of palladium catalyst to get the chiral 1,4-amino alcohols. The catalytic effectiveness of these chiral 1,4-amino alcohol ligands, (2S,3R)-60, (2S,3R)-61, (2S,3R)-62 and (2S,3R)-63 were examined in asymmetric borane reduction and enantioselective diethylzinc addition to benzaldehyde reactions.
Keywords: Amino alcohol, chiral ligand, asymmetric reaction, borane reduction, diethylzinc addition
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Ng, Fei-yeung. "Structure and properties of self-assembled coordination compounds : homoleptic d10-metal aryl/alkylacetylides, ruthenium n-heterocycles and picolinates." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36587126.
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Iqbal, Aman. "Studies on an N-terminal nucleophile hydrolase and enzymes of clavulanic acid biosynthesis." Thesis, University of Oxford, 2008. http://ora.ox.ac.uk/objects/uuid:5ae868c0-007b-4cb8-b4cf-21ab93f69281.
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(3R,5R)-Clavulanic acid is a clinically important inhibitor of Class A β-lactamases. Progress has been made in to establishing the steps of clavulanic acid biosynthesis leading to (3S,5S)-clavaminic acid. However, the mechanism by which (3S,5S)-clavaminic acid is converted to the penultimate intermediate (3R,5R)-clavaldehyde remains elusive. It is believed that the products of the later genes (orf10-orf18) of the clavulanic acid biosynthesis gene cluster are probably involved in this conversion. Part I of this thesis describes biochemical and structural studies carried out on OAT2, a member of N-terminal nucleophile (Ntn) hydrolase superfamily of enzymes. OAT2 has been characterised to be an ornithine acetyl transferase (OAT) and is involved in clavulanic acid biosynthesis. OAT2 catalyses the reversible transfer of the acetyl group between N-acetyl-L-ornithine and L-glutamate. It was found that this reaction is catalysed via the formation of an acyl-enzyme intermediate. Subsequent studies including mass spectrometry, 13C NMR spectroscopy, infrared spectroscopy, X-ray crystallography and molecular dynamics simulations, further confirmed the viability of the intermediate. This acyl-enzyme intermediate of OAT2 was found to be exceptionally stable at physiological pH, as compared to the acyl-enzyme intermediates involved in catalysis by hydrolytic enzymes including proteases, Ntn hydrolases and β-lactamses. The X-ray studies revealed possible reason for this unusual stability. The infrared studies revealed two conformations for the acyl-enzyme. Modeling (MDS) studies assigned one of these to the structure observed by X-ray and proposed the other one to result from a hydroxyl hydrogen 'flip' involving the oxyanion hole component Thr-111 resulting in a singly hydrogen bonded acyl-enzyme intermediate. α, β Subunit co-expression studies with OAT2 were used to investigate the autocatalytic cleavage step. In one case an interesting N-acyl enzyme species was observed. Part II of this thesis describes efforts carried out to characterise the ORF10 and ORF15 proteins of clavulanic acid biosynthesis. ORF10 was characterised to be an 'active' cytochrome P450 and ORF10 crystals were obtained in the presence spinach ferredoxin, highlighting the role of the ferredoxin interaction in assisting ORF10 crystallisation. ORF15 was shown to be a probable peptide transporter, which binds bradykinin as observed in the crystal structure.
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Harrelson, John P. "A comparative study of cytochromes P450 2E1 and 2A6 : substrate dynamics, multiple ligand binding, and adduct formatioin by N-acetyl-m-aminophenol /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/8166.
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Bob-Egbe, Opetoritse. "Development of axially chiral 2-aryl-4-dialkylaminopyridine-N-oxide based catalysts for the sulfonylative kinetic resolution of amines." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9776.
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Lewis base catalysis has been studied extensively in recent years as a powerful tool for introducing asymmetry into a variety of reactions, avoiding the use of expensive and potentially toxic metal catalysts. There is however still ample scope for the development of procedures for the non-enzymatic catalytic kinetic resolution (KR) of amines. Unlike alcohols, the intrinsic high reactivity of amines towards acyl and sulfonyl donors makes their KR highly challenging. As a result, there are relatively few publications on non-enzymatic catalytic KR of amines via acylation1-8 and none via sulfonylation. This thesis describes the development of a new class of chiral 2-aryl-(4-dialkylamino)pyridine-N-oxides (2-Ar-(4-DAAP)-N-oxides) (A), which are chiral by virtue of atropisomerism around the biaryl axis, and their application as catalysts for the KR of amines via sulfonylation. [molecular structure diagram] The use of C-H activation was explored for the development of a concise and modular synthetic procedure to the target catalyst structure. As a result, the key step in our final synthesis is a microwave (MW) assisted C-H halogenation procedure.(9) This reaction provides facile access to a di-ortho functionalised late stage intermediate from which a subsequent Pd catalysed cross coupling with a range of activated aryl partners provides access to an array of chiral catalyst structures. [molecular structure diagram] These catalysts were synthesised for assessment in the kinetic resolution of the axially chiral amine NOBIN, a synthetically useful chiral ligand which suffers from a difficult enantioselective synthesis. [molecular structure diagram] This thesis will provide a description of the synthetic route developed to achiral and chiral catalysts, the dependence of sulfonylation rates on the electronics of the catalyst and the key role of C-H activation in achieving a successful efficient synthesis of the target chiral catalyst structures. *For molecular structure diagrams, please see the PDF of the thesis.
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Balkenhohl, Moritz [Verfasser], and Paul [Akademischer Betreuer] Knochel. "Metalation and amination of N-heterocycles and the halogen/zinc exchange of aryl halides / Moritz Balkenhohl ; Betreuer: Paul Knochel." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/1211957128/34.
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Leslie, J. Michelle. "N-Thiolated b-lactam antibiotics : synthesis and structure-activity studies of C3 oxygenated derivatives and attachement to new, functionalized caprolactone monomers and polymers." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001685.
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Meckle, Manuel [Verfasser]. "Synthesis and properties of fully conjugated cyclo[n]thiophenes and investigation into a boron-templated aryl-coupling method / Manuel Meckle." Ulm : Universität Ulm, 2016. http://d-nb.info/1103052330/34.
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Belot, Vincent. "Accès à une bibliothèque ciblée de n-aryl-thiazoline-2-thiones pour l'établissement d'une nouvelle échelle de taille de substituants usuels." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0408/document.
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Une échelle de taille contenant 20 substituants usuels en chimie a été construite à partir des barrières de rotations de N-aryl-thiazoline-2-thiones. L’énergie d’activation ΔG≠rot qui est mesurée reflète l’encombrement stérique du substituant en ortho du cycle benzénique. Les perturbations électroniques, et les facteurs externes tels que la température ou le solvant sont négligeables. La grande sensibilité du modèle proposé conduit au classement suivant Me > Cl et CN > OMe > OH. Ces classements divergents décrits dans la littérature seront discutés. Une limitation du modèle proposé concerne les substituants très volumineux comme le CF3 et l’iPr qui apparaissent plus petit qu’ils ne le sont en réalité à cause d’un encombrement stérique dans l’état fondamental qui abaissent la valeur de la barrière de rotation<br>A steric scale of 20 recurrent groups was established from comparison of rotational barriers on N-(o-substituted-aryl)-thiazoline-2-thione atropisomers. The resulting energy of activation ΔG≠rot reflects the spatial requirement of the ortho substituent borne by the aryl moiety, electronic aspects and external parameters (temperature and solvent) generating negligible contributions. Concerning divergent rankings reported in literature, the great sensitivity of this model allowed to show unambiguously that a methyl appears bigger than a chlorine, and gave the following order in size: CN > OMe > OH. For the very bulky CF3 and iPr groups, constraints in the ground state decreased the expected ΔG≠rot values resulting in a minimization of their apparent sizes
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Pialat, Amélie. "Formation de liaisons C-N et C-O par catalyse de coordination ou par oxydation à l'iode hypervalent." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20204/document.
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La fonctionnalisation directe de liaisons C-H offre une alternative plus économe en atomes et étapes que les traditionnelles méthodes de synthèse basées sur la transformation de molécules pré fonctionnalisées. Ainsi, les réactions d'amination intermoléculaire de liaisons C(sp3)-H avec des nitrènoïdes sont généralement effectuées avec des rendements et des régiosélectivités modérés et utilisent pour cela des catalyseurs coûteux. Dans ce contexte, nous avons créé de nouveaux systèmes bifonctionnels pour la formation de liaisons C-N aliphatiques catalysée par le cuivre et l'argent. Ces systèmes se sont cependant avérés inefficaces dans les conditions réactionnelles utilisées.Les travaux effectués dans le cadre de cette thèse se sont également concentrés sur la fonctionnalisation nucléophile d'anilides par oxydation à l'iode hypervalent. Grâce à cette méthodologie les triflation et triflimidation directes d'acétanilides ont été accomplies dans des conditions oxydantes douces, en présence de triflate et de triflimidate d'argent, respectivement. Ces transformations procèdent avec de bons rendements et présentent une régiosélectivité parfaite pour la position para<br>The direct functionalization of C-H bonds offers an attractive, atom- and step-economical alternative to traditional methods based on functional group transformations. Intermolecular C(sp3)-H amination reactions involving nitrene intermediates usually proceed with moderate yields and regioselectivities. In this context, new bifunctional compounds were developed and applied to copper and silver-catalyzed C-N bond-forming reactions. These systems, however, have been found to be ineffective under the reaction conditions.Our research has also focused on the iodine(III)-mediated nucleophilic functionalization of anilides. The direct triflation and triflimidation of acetanilides were accomplished with the use of affordable and easy-to-handle silver(I) triflate or triflimidate respectively, under mild oxidative conditions, exhibiting perfect regioselectivity for the para position. A complete optimization of the reaction conditions and an evaluation of the scope allowed us to prepare a variety of diversely substituted aryltriflates (and nonaflates) in synthetically useful yields
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Würtz, Sebastian. "Palladium-Katalyse Synthese und Anwendung neuartiger chiraler und achiraler N-heterocyclischer Carbene (NHC) in Palladium-katalysierten Kreuzkupplungen und Palladium-katalysierte oxidative Cyclisierung von N-Aryl-Enaminen zur Synthese hochfunktionalisierter Indole." Lichtenberg (Odw.) Harland Media, 2008. http://d-nb.info/992466458/04.
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Whipp, Christopher J. "Part 1: The Direct Arylation of Azine N-Oxides with Aryl Triflates Part 2: The Site-Selective Direct Arylation of Substituted Indoles." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28792.
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Part 1: The Direct Arylation of Azine N -Oxides with Aryl Triflates. Two sets of conditions for the palladium-catalyzed direct arylation of azine N-oxides with aryl triflates have been developed. Using palladium(II) acetate, a trialkylphosphine ligand, a carbonate base and pivalic acid, both mono- and diarylated azine N-oxides could be synthesized in good to excellent yields.*
The reaction regioselectivity was examined for 3-substituted pyridine N-oxides, with arylation at C2 being favoured. The methodology was applied to the efficient formal synthesis of a biologically active diaryl pyridine.
Part 2: The Site-Selective Direct Arylation of Substituted Indoles. Initial studies into the site selectivity of the direct arylation reaction were conducted. Several competition studies were performed using various methodologies to determine the selectivity, if any, between two arenes capable of undergoing direct arylation. It was found that selectivity was greatest when competition was between one electron-rich and one electron-poor arene.*
From these results a substituted indole was synthesized and subsequently derivatized at three different positions. It was demonstrated that site selectivity on a complex molecule could be achieved through careful selection of reaction conditions.
*Please refer to dissertation for diagrams.
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May, Tricia Lee. "Copper-Based N-Heterocyclic Carbene Complexes for Catalytic Enantioselective Conjugate Additions of Alkyl-, Aryl- and Vinyl-Based Nucleophiles to Form All-Carbon Quaternary Stereogenic Centers." Thesis, Boston College, 2011. http://hdl.handle.net/2345/2650.
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Thesis advisor: Amir H. Hoveyda<br>Chapter 1 Enantioselective Conjugate Additions of Carbon Nucleophiles to Activated Olefins: Preparation of Enantioenriched Compounds Containing All-Carbon Quaternary Stereogenic Centers. Methods for enantioselective conjugate addition of nucleophiles to activated olefins generating products containing all-carbon quaternary stereogenic centers are critically reviewed. Enantioselective conjugate addition has been shown to be a powerful and concise approach to construct carbon-carbon bonds to prepare compounds containing sterically hindered stereogenic centers and has seen great advances in the past several years. Owing to the difficult nature of additions to relatively unreactive conjugate acceptors, compared to additions generating tertiary stereogenic centers, and construction of a sterically-hindered bond, in many cases, new and active catalysts had to be developed. The review discusses the areas where significant advances have been made as well as current limitations and future outlook. Chapter 2 Development of New and Active Catalysts for Cu-Catalyzed Enantioselective Conjugate Addition of Alkyl- and Arylzinc Reagent. Through development of new chiral catalysts, we have found an active and enantiodiscriminating bidentate, sulfonate-containing NHC-Cu catalyst that effects enantioselective conjugate addition of alkyl- and arylzinc reagents on notoriously difficult trisubstituted cyclic enones. Products are prepared with high levels of selectivity and participate in a variety of further functionalizations. The enantioselective additions are efficient and practical, not requiring rigorously anhydrous or oxygen-free conditions. Chapter 3 Cu-Catalyzed Enantioselective Conjugate Addition of Alkyl- and Arylaluminum Reagents to Trisubstituted Enones. Outlined in this chapter is the first effective solution for Cu-catalyzed enantioselective addition of alkyl and aryl nucleophiles to trisubstituted cyclopentenones generating products bearing a β-all-carbon quaternary stereogenic center. Products are obtained in up to 97% yield and 99:1 er, only requiring 5 mol % of an in situ generated Cu-NHC catalyst. The methodology was highlighted as one of the key steps in the total synthesis of clavirolide C. Not only five-membered rings, but six- and seven-membered rings serve as proficient partners in the enantioselective process. Moreover, in cases for the enantioselective aryl addition, in situ prepared Me<sub>2</sub>AlAr can be used without purification, filtration, or isolation, only requiring the corresponding aryl halides. The additions have also been extended to trisubstituted unsaturated lactones and chromones. Chapter 4 Cu-Catalyzed Enantioselective Conjugate Addition of Vinylaluminum Reagents to Cyclic Trisubstituted Enones. An enantioselective protocol for the formation of β,β-disubstituted cyclic ketones containing a synthetically versatile vinylsilane is disclosed. Enantioselective conjugate addition of in situ prepared silyl-substituted vinylaluminum reagents to β,β-unsaturated ketones promoted by 5 mol % of chiral Cu-NHC complexes delivers desired products with high efficiency (up to 95% yield after purification) and enantioselectivities (up to >98:<2 er). Several functionalizations utilizing the vinylsilanes, vicinal to an all-carbon quaternary stereogenic center, are shown, including an oxidative rearrangement, vinyl iodide formation and protodesilylation, accessing products not previously attainable. Furthermore, the enantioselective protocol is demonstrated as the key transformation in the total synthesis of riccardiphenol B<br>Thesis (PhD) — Boston College, 2011<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
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Cromer, Rémy. "Porphyrines n-substituees : modelisation de l'inhibition d'hemoproteines." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13015.
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Migration cobalt-azote des groupements : phenyl et styryl. L'etude des reactions de migration dans les porphyrines de cobalt(iii) aryliques a justifie l'utilisation de ces dernieres pour modeliser l'hydrazinolyse des hemoproteines. Les porphyrines de cobalt(iii) aryliques ont un comportement analogue a celui des porphyrines de fer(iii) aryliques. Oxydation des styryl -co(iii) porphyrines. Mecanisme de reaction. Extension de cette reaction a la cyclisation en serie arylique qui permet la synthese de la premiere porphyrine n,n'-(phenylene-1,2) analogue du produit d'inhibition suicide obtenu apres activation de l'amino-1 benzotriazole par divers enzymes a cytochrome p-450
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Svensson, Akusjärvi Emma [Verfasser]. "Mechanistic Investigations of the Direct Arylation of Pyridine N-oxides with Bromoarenes and Structure-Reactivity Relationship of Aryl Palladium Complexes in Transmetalations with Organoboron Compounds / Emma Svensson Akusjärvi." Berlin : Freie Universität Berlin, 2018. http://d-nb.info/1176635034/34.
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Platon, Mélanie. "Propriétés et performances de phosphines ferrocéniques dans le couplage C-O, C-S et C-N : nouvelles méthodologies de synthèse au palladium." Phd thesis, Université de Bourgogne, 2012. http://tel.archives-ouvertes.fr/tel-00818998.
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Les ligands multidentes montrent généralement de très bonnes activités dans la catalyse organométallique au palladium à faibles charges. Parmi ces ligands, l'utilisation des ligands polyphosphines ferrocéniques mènent à des résultats intéressants. Des systèmes catalytiques palladium/triphosphine ferrocénique robustes ont permis d'obtenir d'une part des diarylamines et d'autre part des éthers d'aryle et d'hétéroaryle avec de faibles charges catalytiques. Des calculs théoriques de DFT sur le cycle catalytique lors de la formation d'éthers d'aryle et d'hétéroaryle ont été réalisés. La présence d'un troisième groupement phosphino permettrait de stabiliser les états de transition et accélèrerait l'élimination réductrice. Les triarylamines ont pu être obtenues à l'aide d'une diphosphine ferrocénique avec une charge de 2 mol% de palladium. Des résultats modérés à excellents ont été obtenus. Enfin, les thioéthers d'aryle et d'hétéroaryle ont été obtenus avec d'excellents résultats à l'aide d'une tétraphosphine ferrocénique en présence de 0,2 mol% de palladium
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Delamare, Madeleine. "Nouvelles voies de synthèse d'hétérocycles polyazanaphtalènes en vue de leur application en pharmacie, en agro-industrie et en phytochimie." Rouen, 1998. http://www.theses.fr/1998ROUES024.
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L'activité de produits imidazolés vis-à-vis de l'inhibition de la farnésyl transférase a conduit au développement d'un programme de recherche industriel ayant pour base d'une part un azole et d'autre part un hétérocycle permettant une reconnaissance enzymatique spécifique. Dans le cadre de ce programme, nous nous sommes intéressés aux synthèses de divers hétérocycles de structures polyazanaphtalènes. Ainsi, des 6-acylisoquinol-1(2H)-ones, des 6- et 7-formyl-1,8-naphtyridin-2-ones et des 6- et 7-formyl-1,5-naphtyridin-2-ones, pouvant être substituées en position 3 par un groupe méthyle et en position 4 par un groupe phényle ont été préparées. La méthodologie employée pour la préparation de ces molécules repose essentiellement sur l'utilisation des réactions de métallation sur des dérivés para-substitués du N-allylbenzamide et des dérivés substitues des 2- et 3-aminopyridines. Les synthèses mises en oeuvre ont permis d'accéder en peu d'étapes à des systèmes hétérobicycliques différemment substitués avec de bons résultats.
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Kerbal, Abdelali. "Cycloaddition de diarylnitrilimines et d'azides sur diverses énones et énamines dérivées d'indadones et de tétralones : Regiochimie, diasteréochimie et transformation des cycloadduits." Besançon, 1988. http://www.theses.fr/1988BESA2038.
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La cycloaddition dipolaire-1,3 des diarylnitrilimines sur diverses enones a double-liaison dipolarophile juxtacyclique est regiospecifique. Lorsque le dipolarophile présente deux faces diastereotopiques, l'approche dipole-dipolarographie se fait du côté le moins encombré : - de façon diastereospecifique sur les enones dérivées de l'indanone-1 substituée ou de la tetralone-1 substituée lorsque ces dernières portent en -3 ou -4 un substituant occupant une position axiale - de facon diastereoselective sur les enones dérivées de la tetralone-1 portant un substituant en -4 qui peut adopter une disposition équatoriale. Ces résultats qui mettent en évidence l'importance des facteurs conformationnels, sont généraux et ont pu être étendus aux cas d'autres enones dérivées des chromanones et isothiochromanone
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Ibn, Ahmed Saïd. "Une approche à la synthèse enantiospecifique d'alcaloïdes du narcisse." Nancy 1, 1988. http://www.theses.fr/1988NAN10150.
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Approche de la synthèse d'alcaloïdes derivés de dioxolo-1,3 (4,5-J) phénanthridine : la première partie traite de quelques analogues non cyclisés (synthèse et étude de l'activité anticancéreuse) ; la deuxième partie résume les différents essais de synthèse totale de ces alcaloïdes et particulièrement de l'O-acétyl-2 DI-O-benzyl-3,4 désoxo lycoricidine
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Chao, Hsin-Chi, and 趙星智. "Preparation of N-aryl Aziridines." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/57550471258830594389.
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碩士<br>中原大學<br>化學研究所<br>100<br>Aziridine, a high-application value compounds, not only widely used in organic synthesis reactions but also in the synthesis of natural products and medicine often have the structure of the aziridine.In recent years,many chemists put into the reserch because of the aziridine with the anti-tumor biological activity.
In this paper, we used a series of aryl azide mix in electron- withdrawing alkenes, under high temperature and solvent environment, prepared a series of corresponding phenyl- substituted nitrogen base aziridine.
The characteristics of this experiment is that without complicated steps,it can be simple and efficient to synthesis aziridine. In addition, we also try to adjust the reaction conditions, to makes the reaction selectivity better thereby allowing the production yield increase.
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Lai, Huei-Jia, and 賴慧嘉. "Synthesis and Spectroscopic Study of N-(4-aryl)-5-methylisoxazol-4-carboxamide and N-(4-aryl)-3-methylisoxazol-4-carboxamide." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/40426157355462648267.
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碩士<br>亞洲大學<br>生物科技學系碩士班<br>98<br>Isoxazole is a class of heterocyclic compounds having a remarkable
number of applications and has been demonstrated to be very versatile
building blocks in organic synthesis.
Two series of N-(4-aryl)-5-methylisoxazol-4-carboxamide and
N-(4-aryl)-3-methylisoxazol-4-carboxamide were synthesized and
spectroscopic studied to investigate the variation reaction on the substutents phenyl ring. The isoxazole derivatives were prepared from the reaction 5-methylisoxazole-4-carbonyl chloride or 3-methylisoxazole-4-carbonyl chloride and substituted anilines in good
yields.
The SCS on C-13 NMR studies on the series of N-(4-aryl)-5-methyl-
isoxazol-4-carboxamide showed that the aryl substituent effect on
isoxazole’s C5 via long distance Hammett substituent effect (slope = +1.3, r2 = 0.94).
N-(4-aryl)-3-methylisoxazol-4-carboxamide was first synthesized and
characterized by means of melting point, elemental analysis, IR, UV, EI-MS, 1H NMR spectrum and 13C NMR spectrum analysis.
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Lesenyeho, Lehlogonolo Godfrey. "Palladium-catalyzed heteroannulation of 2-ARYL- 3-IODO-4-(Phenylamino)quinolines and 4-(N,N-allylphenylamino)-2-ARYL-3-iodoquinolines." Diss., 2010. http://hdl.handle.net/10500/3970.
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The previously described 2-aryl-4-chloro-3-iodoquinolines were prepared following literature procedure and in turn converted to the corresponding hitherto unknown 2-aryl-3-iodo-4-(phenylamino)quinoline derivatives using aniline in refluxing ethanol. These 2-aryl-3-iodo-4-(phenylamino)quinolines were reacted with allybromide in ethanol at room temperature to afford 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives. The 2-aryl-3-iodo-4-(phenylamino)quinoline and 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were subjected to metal-catalysed carbon-carbon bond formations. Palladium(0)-copper iodide catalysed Sonogashira cross-coupling of 2-aryl-3-iodo-4-(phenylamino)quinoline with terminal alkynes afforded series of 1,2,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines in a single step operation. On the other hand, the 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were found to undergo palladium-catalysed intramolecular Heck reaction to yield the corresponding 1,3,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines. All new compounds were characterized by using a combination of NMR (1H and 13C), IR, mass spectroscopic techniques as well as elemental analysis.<br>Chemistry<br>MSc. (Chemistry)
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Yi-JieHuang and 黃奕傑. "The Applications of Sulfonyl Radical on The Synthesis of 2-Quinolinones from N-aryl Amides and Quinolines from N-aryl Enamines." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/42836009015597216859.
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碩士<br>國立成功大學<br>化學系<br>104<br>Recently, there has been a growing interest in the application of free radical cyclization reactions to the formation of ring systems. Free radical reactions mediated by sulfonyl radicals have been noted by several groups. Free radical of sulfonyl radical can undergo addition reaction with unsaturated bond generate radical intermediate to undergo either 6-membered or 5-membered ring cyclization onto the aromatic ring effectively and provide synthetically useful methods for the syntheses of 2-quinolinones and quinolines. This thesis is divided into two parts：(1) This research use a catalytic amount of silver(I) with potassium persulfate to oxidizing p-toluenesulfinate sodium salt in heating condition is taken as sulfonyl radical source, and then induced free radical cyclization reaction with sulfonamide compounds in our report. (2) This research use excess manganese(III) acetate with p-toluenesulfinate sodium salt to generate sulfonyl radical source with dimethyl 2-((2-ethynylphenyl)amino)maleate derivatives to get various quinoline derivatives with the different function group.
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Wang, Wen-Yang, and 王文揚. "I.Aliphatic Hydroxamates Capped with Substituted Aryl Indole as Histone Deacetylase InhibitorsII.Structure Optimization for Ortho-Aryl N-Hydroxycinnamides as HDAC 8 Isoform-Selective Inhibitors against Cancer CellsII.Structure Optimization forOrtho-Aryl N-Hydroxycinnamides as." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/55xw6v.
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碩士<br>臺北醫學大學<br>生藥學研究所<br>102<br>Histone deacetylase (HDAC) inhibitors are regarded as a promising therapeutic for treatment of cancer. However, current HDAC inhibitors have some unsatisfactory problems, including limited potency for solid tumors and dose-limiting side effects. This study includes： I. Aliphatic Hydroxamates Capped with Substituted Aryl Indole as Histone Deacetylase Inhibitors against Cancer Cells; II. Structure Optimization for Ortho-Aryl N-Hydroxycinnamides as HDAC8 Isoform-Selective Inhibitors I. Currently, SAHA and Romidepsin both were FDA-approved HDAC inhibitors to treat Cutaneous T cell lymphoma (CTCL). Depite their success in hematopoietic malignancy, HDAC inhibitors in clinical trials had still failed to heal solid tumorsm, thus, encouraging us to develop novel inhibitors against these tumors. The pharmacophore of SAHA is composed of three parts such as a zinc-binding group, a hydrophobic linker and a surface recognition cap. In this study, we used aryl indole as a surface recognition cap to develop a novel series of HDAC inhibitors. All compounds were screened for HeLa nucleus HDACs enzyme inhibition. Among them, compounds 4a, 4b, 4d and 6 exhibited potent inhibitory activity (IC50 = 209, 117, 104, 232 nM) comparable to SAHA (IC50 = 275 nM). Notably, compound 4d had the best cytotoxicity against non-small-cell lung carcinoma A549 cells (GI50 = 0.65 μM) compared to SAHA (GI50 = 1.50 μM). Western
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blot analysis related to intracellular HDAC inhibiton indicated compounds 4a, 4c, and 4d had significant effect on enhancing acetylation histone H3 and p21 in HT29 cells comparable to SAHA. Further molecular docking of 4d and SAHA interacted to histone deacetylase like protein (HDLP) demonstrated that the benzenesulfonyl of compound 4d may offer more interaction with the enzyme surface at HDAC than SAHA.Cutaneous T cell lymphoma (CTCL) II. HDAC family comprises eighteen isofirms. Studies had revealed that selective HDAC inhibitors may have less side effects than pan ones. We had delveloped a lead ortho-biphenyl N-hydroxycinnamide A22d with potent HDAC8 inhibition. Based on the molecular docking result for A22d with HDAC8, we extensively added different function groups to biphenyl moiety to enhance their enzyme inhibitory activity. Seven novelly synthesized compounds were screened for anti-HDAC 8 activity and compound 11d showed the best activity (IC50 = 29.3 nM) comparable to PCI-34051 (IC50 = 27.1 nM), a reportedly potent HDAC8 inhibitor. Molecular docking analysis suggested compound 11d may interact with HDAC 8 in a specific sub-pocket which allows to provide selectivity toward HDAC 8. Furthermore, based on the potent cytotoxicity by our previously developed HDAC 8 inhibitor A5e against tumor cells, we synthesized seven additional novel inhibitors. Of these, compounds 21 and 25 had moderate HDAC 8 inhibitory activity (IC50 = 292.5, 341.2 nM). Further cellular effects of HDAC 8 inhibitors in this study are being undertaken.
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Krishnan, P. Santhana Gopala. "Synthesis and characterisation of n-aryl methacrylatoethyl carbamate homopolymers and copolymers." Thesis, 1992. http://localhost:8080/xmlui/handle/12345678/3094.
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呂亭宜. "The Palladium-Catalyzed Cross-Coupling Reaction of Aryl- and Alkenylboron Compound with 2-Bromo-N,N-dimethylacetamide." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/41718512342460728665.
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碩士<br>國立中正大學<br>化學研究所<br>91<br>α-Arylamides have potential medical and agricultural applications. β,γ-Unsaturated amides are versatile synthetic intermediates. However, few general methods for their preparation have been reported.
In view of the limited number of methodologies for the synthesis of a-arylamides and β,γ-unsaturated amides, we have explored the extension of the palladium-catalyzed cross-coupling of aryl- and alkenylboron compound with 2-bromo-N,N- dimethylacetamide.
Thus, a-bromoacetamide (1 equiv) was reacted with arylboron compound (1 equiv) in the presence of Pd(dba)2 (3 mol %), PCy3 (6 mol %), K3PO4 (3.4 equiv) in THF under nitrogen atmosphere at 70°C to give a-arylamides in moderate to good yields. The addition of 10 mol % of hydroquinone may further improve the yield to ~ 90 %.
The optimum condition is also used to synthesize the a-vinyl- acetamide. And the desired cross-coupling products were obtained in 45-77 % of yields with good stereoselectivities (> 90 %).
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Kumar, Ajay K. "Synthesis of biologically active heterocycles VIA imines, Aziridines and N-aryl maleimides." Thesis, 2000. http://hdl.handle.net/2009/2250.
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