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Kitagawa, Kristen. "Studies in the asymmetric reduction of (3s)-3-amino-1-chloro-4-phenyl-2-butanone derivatives." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/39464.
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This thesis focuses on the asymmetric reduction of N-protected derivatives of (3S)-3-amino-1-chloro-4-phenyl-2-butanone to their corresponding diastereomeric alcohol products, which are key intermediates in the synthesis of HIV protease inhibitors. Although the stereoselective synthesis of the (S,S) alcohol product is easily achieved, preparing the (R,S) diastereomer is much more challenging. I investigated three diastereoselective reduction processes: 1) Meerwein-Ponndorf-Verley (MPV) reduction, 2) asymmetric transfer hydrogenation, and 3) boron reducing agents. The diastereoselectivity of the MPV reduction still favored the (S,S) product; however, I discovered a significant rate enhancement when the standard catalyst (aluminum isopropoxide) was replaced with aluminum tert-butoxide. Many reaction variables were investigated in the asymmetric transfer hydrogenation reaction and the diastereoselectivity was improved to give a ratio of the desired (R,S) diastereomer to the undesired (S,S) alcohol of 9.5:1. Using chiral oxazaborolidine catalysts, an unprecedented (R,S) to (S,S) ratio of 9.5:1 was achieved. Finally, I investigated the effect of the N-protecting group on the stereoselectivity of the reduction. When the original boc-protecting group was replaced with a phthalimide group, the diastereoselectivity of the MPV reduction was reversed to favor the desired (R,S) product.
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Fowles, A. M. "The preparation and biological activity of some 2-alkylated gibberellin Asub(4) and Asub(1) derivatives." Thesis, University of Bristol, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370827.
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Nguyen, Dao. "Design, Synthesis, and Characterization of Novel Hydrophilic Fluorene-Based Derivatives for Bioimaging Applications." Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2842.
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In this work, hydrophilic fluorene-based derivatives that contain ethylene oxide substituents, have been synthesized and characterized for potential use as new fluorophores for bioimaging applications and for fluorescence sensing of heavy metals. Symmetrical and unsymmetrical fluorene derivatives based on structural types of acceptor-pi-acceptor, acceptor-pi-donor, and donor-pi-donor were characterized by TGA, UV-vis absorption, fluorescence emission, lifetime, anisotropy, and two-photon absorption (2PA) cross section. They were found to possess high thermal stability, high photostability, high fluorescence quantum yields, and generally large two-photon absorption cross sections, making them quite suitable for new probes in single-photon absorption and two-photon absorption fluorescence microscopy imaging. Novel hydrophilic fluorene derivatives were synthesized from fluorene in multiple steps employing the metal-catalyzed Heck coupling reaction, the Stille reaction, the Sonogashira reaction, the Ullmann condensation reaction, and "click" chemistry. To increase the hydrophilicity of the new compounds, ethylene oxide substituents were utilized for to impart water solubility. An alternative alkylation methodology using ethyleneoxy tosylates was introduced for the synthesis of ethylene oxide-containing fluorene derivatives. Several of these hydrophilic derivatives were incubated into various cell lines as new probes for both conventional and two-photon absorption fluorescence bioimaging. These compounds were biocompatible, exhibiting low cytotoxicity as determined by cell viability studies, and displayed colocalization for selected cellular organelles. In addition, hydrophilic bis(1,2,3-triazolyl)fluorene derivatives were found to exhibit sensitive fluorescence responses in the presence of certain heavy metal, and were selective for sensing zinc and mercury over other a number of other metal ions relevant to living cells or other biological environments. The UV-vis absorption and fluorescence emission spectra of the complexes exhibited a blue-shifted absorption and emission for selective metal chelation upon binding to zinc and mercury(II) ions, resulting in an approximately two-fold enhanced fluorescence response. Fluorescence titration studies revealed that the complexes of 1:2 and 1:3 ligand to metal formed with binding constant values of 108 and 1014 for zinc and mercury ions, respectively. Finally, preliminary experiments were performed to explore the possibility of employing select hydrophilic fluorene-based derivatives in the synthesis of hydrophilic fluorescent gold nanoparticles. Although results are very preliminary, the aim is to use such materials for other biomedical applications, such as surface enhanced scattering resonance and noninvasive photothermal therapy to diagnose and to treat cancers. Thus, this research had led to the discovery of alternative methodologies for synthesis of hydrophilic fluorene derivatives by alkylation with alkyl tosylates and synthesis of hydrophilic fluorescent molecule capped gold nanoparticles. Furthermore, several novel hydrophilic fluorene-based derivatives were synthesized and characterized for their linear and nonlinear photophysical properties, and are now available for further examination of their bioimaging and sensing applications.<br>Ph.D.<br>Department of Chemistry<br>Sciences<br>Chemistry PhD
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Osazee, Joseph Osamudiamen. "Molecular Docking, Synthesis and Evaluation of Pyrrolo[2,1-c][1,4]benzodiazepines Derivatives as Non-β-lactam β-lactamases Inhibitors". Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etd/3082.
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Our research aim was to design, synthesize, and study the competitive enzyme inhibition kinetics of pyrrolo[2,1-c][1,4]benzodiazepine (PBD) derivatives as potential non-²-lactam ²-lactamase inhibitors. All compounds (1-13) passed the Lipinski’s rule of 5 test and were docked into the active site of TEM-1 ²-lactamase. PBD derivatives 1-7 were synthesized in high yields and tested for their potency against TEM-1 and P99 ²-lactamases. Kinetic data showed that compounds 1, 4, 5, and 7 possessed inhibitory activity against TEM-1 ranging from 4-34 %. Docking results revealed significant interactive spanning of the active site of TEM-1 by PBDs. The limited inhibitory activity of the compounds, 1-7 could be attributed to the lack of solubility and bulky nature of the molecules, thus limiting the optimal ligand-enzyme interactions. 1,2,4- Oxadiazolinones (8-13) were further synthesized to reduce the steric hindrance of the PBD scaffolds while promoting the electrophilicity of the potentially active lactam and also evaluated for potency.
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KROBER, JONAS. "Materiaux moleculaires a transition de spin pour l'affichage : derives du fe (ii) -1, 2, 4 - triazole." Paris 11, 1994. http://www.theses.fr/1994PA112091.
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Ce travail de these est consacre a l'etude du phenomene de transition du spin (ts) dans les composes a base moleculaire contenant des ions fe #i#i entoures de derives 1,2,4-triazoles. La ts se manifeste dans ces composes par un passage thermoinduit de l'etat fondamental bas-spin diamagnetique (bs ou s=0) vers un etat legerement excite paramagnetique haut-spin (hs ou s=2). Ce passage est accompagne d'un effet thermochrome important du rouge vers le blanc. Un des buts principaux etait l'utilisation de cet effet thermochrome afin de realiser des dispositifs servant au stockage de l'information, le premier objectif etant des dispositifs d'affichage. A cette fin, les composes doivent presenter une large hysteresis thermique, de l'ordre de plusieurs dizaines de kelvin et il est crucial que ces effets se manifestent aussi pres que possible de la temperature (t) ambiante. Un premier candidat potentiel etait le compose fe(htrz)#2(trz)bf#4 ou htrz represente le 1,2,4-1h-triazole et trz la base correspondante. Ce compose presente une hysteresis tres large, d'environ 50 k, avec des ts tres abruptes (moins que 5 k). Les proprietes de la ts dependent beaucoup de la preparation du compose. Le compose non deprotone fe(htrz)#3(bf#4)#2 presente en plus d'une hysteresis proche de l'ambiante une transition de phase a 150c qui deplace les t de la ts reversiblement en dessous de l'ambiante. Potentiellement ce compose permet l'acces a des hysteresis de 100 k. L'ajustement des t de la ts par dopage partiel du ligand est etudie pour le compose fe(htrz)#3#-#3#(nh#2trz)#3#(clo#4)#2 (nh#2trz=4-amino-1,2,4-triazole) presentant pour =0,05 une boucle d'hysteresis centree autour de la t ambiante. Le remplacement de la substitution de bf#4 par br#- dans le compose fe(nh#2trz)#3(bf#4)#2 conduit a un deplacement de la t de la ts autour de l'ambiante et celle-ci devient beaucoup plus abrupte. Tous ces composes ont des structures polymeriques. Ils se presentent sans doute sous forme de chaines. Afin de comprendre les proprietes physiques de ces composes qui sont etroitement liees a leurs structures, nous avons etudie par diffraction des rayons x la structure de deux composes, zntrzc1, presentant une structure lamellaire et le compose trinucleaire fe#3(me#2ntrz)#6(h#2o)#6(clo#4)#6 (me#2ntrz=4-dimethylamino-1,2,4-triazole). Certains des composes decrits dans cette these ont conduit a des dispositifs deja tres proches du marche. Cette composante de notre travail a ete menee a bien en collaboration avec un partenaire industriel
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El, Haj Brahim Ichrak. "Préparation stéréosélective de 2-alcynyldiols-1,3 ou 2-alcynylaminoalcools-1,3 : synthèse des hétérocycles condensés issus du 2- aminobenzonitrile." Electronic Thesis or Diss., Sorbonne université, 2023. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2023SORUS495.pdf.
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Cette thèse s'est orientée autour de deux axes de recherche distincts. En premier lieu, nous avons exploré la synthèse des 4-hydroxy-1-boryl-1-allenylsilanes, en adoptant une approche innovante à partir d'époxydes acétyléniques et du (triéthylsilyl)pinacolborane. Cette méthode a permis une préparation stéréosélective et stéréospécifique d'allénylboranes, suivant un mécanisme SNi anti. De plus, l'utilisation de ces 4-hydroxy-1-boryl-1-allenylsilanes pour la propargylation des aldéhydes a conduit, de manière stéréosélective, aux 2-alcynyldiols-1,3. Un état de transition impliquant une structure à six chaînons fermés a été proposé pour cette transformation, suggérant un mécanisme SE2’. L'ampleur et les limitations de ces deux processus ont été rigoureusement examinées. Ensuite, le second aspect de cette thèse a concerné la synthèse de composés hétérocycliques à partir du 2-aminobenzonitrile, en mettant l'accent sur le 1,2,4-triazole. Nous avons par la suite élaboré des dimères et étudié leur réactivité envers des électrophiles, tels que le hexaméthylphosphoramide, avec l'objectif de créer des dérivés de diazaphorine. À l'heure actuelle, une analyse est en cours pour évaluer les propriétés antioxydantes des molécules récemment synthétisées, en particulier des dimères iminiques et phosphoazotés<br>This thesis revolved around two distinct research avenues. Firstly, we delved into the synthesis of 4-hydroxy-1-boryl-1-allenylsilanes, adopting an innovative approach using acetylenic epoxide and silylborane. This method enabled a stereoselective and stereospecific preparation of allenylboranes, following an SNi anti mechanism. Moreover, we employed these allenes for the propargylation of aldehydes, which led to the stereoselective formation of the corresponding 2-alkynyl-1,3-diols. A transition state involving a closed six-membered ring structure was proposed for this transformation, suggesting an SE2' mechanism. The scope and limitations of these processes were meticulously assessed. Subsequently, the second focus of the thesis pertained to the synthesis of heterocyclic compounds starting from 2-aminobenzonitrile, with a particular emphasis on the 1,2,4-triazole. Following this, we synthesized dimers and investigated their reactivity towards electrophiles, such as hexamethylphosphoramide, aiming to generate diazaphorine derivatives. As of now, an evaluation is underway to gauge the antioxidant properties of the newly synthesized molecules, especially the iminic and phosphoazo dimers
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chaudhary, Arpana S. "Inhibitors of SecA as Potential Antimicrobial Agents." Digital Archive @ GSU, 2013. http://digitalarchive.gsu.edu/chemistry_diss/77.
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Protein translocation is essential for bacterial survival and the most important translocation mechanism in bacteria is the secretion (Sec) pathway. Thus targeting Sec pathway is a promising strategy for developing novel antibacterial therapeutics.
We report the design, syntheses, mechanistic studies and structure-activity relationship studies using HQSAR and 3-D QSAR Topomer CoMFA analyses of 4-oxo-5-cyano thiouracil derivatives. In summary, introduction of polar group such as –N3 and linker groups such as –CH2-O- enhanced the potency as well as logP and logS several fold.
We also report the discovery, optimization and structure-activity relationship study of 1,2,4-triazole containing pyrimidines as novel, highly potent antimicrobial agents. A number of inhibitors have been found to inhibit microbial growth at high nanomolar concentrations.
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Ciccolini, Cecilia. "Synthesis of Mono and Poly-Heterocycles starting from 1,2-Diaza-1,3-Dienes (or precursors) as Building Blocks." Doctoral thesis, Urbino, 2020. http://hdl.handle.net/11576/2674162.
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Ju, Chen Hui, and 陳慧茹. "The study on the synthesis of 1, 2-dialkoxycalix[4]arenes via benzoate derivatives." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/61630872816837131132.
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碩士<br>中國文化大學<br>應用化學研究所<br>97<br>Abstract
Calixarenes, which are cyclic oligomers of p-substituted phenols and formaldehyde , are able to include small organic molecules or metal ions within the molecular cavities to form“ host-guest”complexes. These phenomena have been proposed in the applications of micro-analysis, ion separation, and enzyme-mimic studies. The main purpose of this thesis is to study the synthesis of calix[4]arene 1,2-dialkyl ethers .
In the basic conditions, p-tert-butylphenol were polymerized with formaldehyde to form a yellowish precursor. Refluxing of this precursor in diphenyl ether yielded the p-tert-butylcalix[4]arene (1). The AlCl3 catalyzed reverse Friedel-Crafts reaction were then applied to remove the p-tert-butyl groups and gave parent calix[4]arene (6).
In our earlier studies on the preparation of calix[4]arene ethers, we have noticed that in the presence of sodium methoxide , the monoalkylated calix[4]arenes can be prepared by refluxing calix[4]arene with alkyl halides in CH3CN. Five different alkyl halides, iodoethane, 1-iodopropane, 1-iodobutane, allyl bromide, and benzyl bromide, were applied in this synthetic procedure.
Esterification of those monoalkylated calix[4]arenes 29-33 with an excess of benzoyl chloride in pyridine produced the corresponding 25-alkoxy-27-benzoyloxy-26,28-dihydroxycalix[4]arenes 34-38 and 25,26-dibenzoyloxy-27-alkoxy-28-hydroxycalix[4]arenes 39-43 . Products 34-38 were treated with NaH and alkyl halides in CH3CN to introduce the second alkyl ether linkage and yielded 25,26-dialkoxy -27-benzoyloxy-28-hydroxycalix[4]arenes 44、45. The removal of benzoate moieties in basic conditions would yield the corresponding final products,1,2-dialkoxycalix[4]arenes 46、47.
All the new products which were produced in this thesis were characterized by 1H-NMR, 13C-NMR, COSY, and FAB-MS. The synthetic procedure for 1,2-dialkoxycalix[4]arenes were also discussed in this thesis.
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Wang, Yu-Yun, and 王雨筠. "The Synthesis of Calix[4]arenes with (1) Distal Anthryl-triazoles and Acid Derivatives (2) Distal Bis-Pyrenyl-ester-triazoles for Metal Ion Sensing Studies." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/18427518349799494126.
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碩士<br>國立交通大學<br>應用化學系所<br>97<br>(1) The Synthesis of calix[4]arenes with Distal Anthryl-triazoles and Acid Derivatives for Metal ion Sensing Studies.
We used the Click Chemistry to modify the lower rim of calix[4]arenes with a triazole cationic binding site, and an anthracene as a fluorophore. After we incorporating a second acid derivatives group into 5a, compounds 6a�{9a were obtained as fluoroionophores for metal ions. Compounds 5a�{9a and control compound 10a showed fluorescence quenching toward Cu2+, Hg2+, and Cr3+ ions. Besides that, 6a also showed a slight fluorescence quenching toward Pb2+ and Mn2+ ions; 8a showed fluorescence enhancement toward Ba2+, Ca2+, Cd2+, Li+, Mg2+, Pb2+ and Zn2+ ions; 9a showed fluorescence enhancement toward Ag+ and Cd2+. We inferred that the functional groups (amide and thioamide) of 8a and 9a might donate electrons to the anthryl group via PET mechanism, thus the fluorescence of anthryl group was quenched. When the functional groups of 8a and 9a bind with metal ions, the metal ions may inhibit the PET mechanism, and therefore enhance the fluorescence. Possible binding modes of these metal complexes were proposed based on 1H NMR titration experiments.
(2) The Synthesis of calix[4]arenes with Distal Pyrenyl-ester-triazoles for Metal ion Sensing Studies.
The lower-rim of calix[4]arenes was modified with triazoles as the cationic binding sites, and pyrenes as the fluorophores. Mono-substituted compound 15, bis-substituted compound 16, phenol protected compound 18 and control compound 14 were synthesized. Both 14 and 15 showed fluorescence quenching toward Cu2+, Hg2+ and Cr3+ ions. 16 showed both monomer and excimer fluorescence quenching toward Cu2+and Cr3+, but showed monomer enhancement and excimer quenching toward Hg2+. Compound 18 showed monomer enhancement and excimer quenching toward Ag+ and Zn2+ besides Cu2+, Hg2+ and Cr3+ ions. Note that the complex of 18˙Cu2+ formed a static excimer. We used 1H NMR titration experiment to determine possible binding modes of these metal complexes and proved that the hydroxyl group of 16 proceeded oxidation-reduction with Cu2+.
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Huang, Chun-Lung, and 黃俊龍. "Synthesis and biological activity of 1-benzyl-4-hydroxy-3-phenylquinolin-2(1H)-one derivatives." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/37426286995940238871.
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碩士<br>中國醫藥大學<br>藥物化學研究所碩士班<br>94<br>The dissertation is based on the structure of 4-hydroxy- quinolin-2-(1H)-ones. In order to synthesize a series of derivatives of 1-benzyl-4-hydroxy-3-phenylquinolin-2(1H)-one (26a-g, 27a-g, 28, 29), Using the Bheemashankar′s solution-phase combinatorial synthetic method. The starting material is methyl anthranilate (16) that is condensated with 4-substituted-benzaldehydes 17a-h to obtain the 19a-h. On the other hand, 4-cyanophenyl acetic acids 20a-d were acylated with thionyl chloride to afford acid chlorides 21a-d. Then, 21a-d and 19a-h are combined by Schotten-Baumann reaction to give 22a-h, 23a-h, 24 and 25, respectively. The last, intermediate 22a-h, 23a-h, 24, 25 are cyclizated by amberlyst A-26 resin (OH- form) and then acidified with trifluroacetic acid to obtain 26a-g, 27a-g, 28 and 29, respectively. Moreover, it is important to evaluate the biological activity from the derivatives, anticipating obtaining leading compounds to establish the structure-activity relationships.
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Rico, Duque Jenny Lorena. "Synthesis of 1,2-methano-tetrahydrofuran derivatives and 1´,2´-methano-2´,3´-dideoxynucleosides as potential antivirals." Thèse, 2018. http://hdl.handle.net/1866/20042.
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CHEN, WEN-TONG, and 陳文童. "The study of conducting polymer solid-state polymerization of 2, 4-hexadiyne-1, 6-diol and its derivatives." Thesis, 1989. http://ndltd.ncl.edu.tw/handle/06051250112823735202.
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Chang, YuanBao, and 張元寶. "Synthetic Studies on 4-Amino-1-[(hydroxyureido)alkyl]-2-quinazolinones and Their Derivatives as Potential HCV NS3 Helicase Inhibitors." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/60261666896350415020.
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碩士<br>國立臺灣大學<br>藥學研究所<br>88<br>Hepatitis C virus (HCV), a virus that infects some 170 million people worldwide, is causing rising rates of liver disease. The necessity of finding potent anti-HCV agents is an urgent task. Hydroxyurea was reported to possess antiviral and antitumor activities as the results of inhibiting DNA synthesis. It is also an analogue of hydroxamic acid, a well-known compound with high affinity for metal ions. These make it of value in the development of anti-HCV agents. In this investigation, a novel series of quinazolinone derivatives comprise of hydroxyurea moiety, such as 4-amino-1-(Nω-hydroxyureidoalkyl)-2-quinazolinone (2a-c), 4-amino-1-(N-carbamoyl-N-hydroxylaminoalkyl)-2-quinazolinone (3a-c), and 4-amino-1-(N-hydroxycarbamoylalkyl)-2-quinazolinone (4a-c), were designed and synthesized. From computer modeling it shows that these compounds bind with HCV helicase on the ATP binding site. This result indicates that quinazolinone derivatives possess the potentiality as HCV helicase inhibitors. In addition, their potential activities to inhibit HCV NS3 helicase are evaluated by ELISA.
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Fang, Yu-Wen, and 方昱文. "Synthesis and Biological Evaluation of (2-(4-Phenyl)-1,3-butadien-1-yl)quinoline-8-ol Derivatives as Anticancer Agents." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/71505737422723661754.
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碩士<br>高雄醫學大學<br>醫藥暨應用化學研究所<br>101<br>(E)-2-(2-(5-nitrofuran-2-yl)vinyl)quinolin-8-ol (HZY-2023) has demonstrated a strong inhibitory effect on difficult ablation period of prostate cancer cells. However, its cytotoxity against normal cells prevents further application. In this study, the alkene between two aromatic rings was replaced by diene to alter the redox properties. This modification improve inhibitory effect and reduced the normal toxiaty aginst cell. The results of biological assay indicated series of derivatives which exhibit selectively cytotoxity against androgen-independent and reduce toxicity on normal cells. Meanwhile, optimization of synthetic conditions focuses on cost efficiency, easy purification and efficiency improvement to afford the target compounds.
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Chen, Yu-Jen, and 陳俞臻. "(1) Temperature and Matrix Effects Dependence on the Triplet Radical Pairs Generated from Photolysis of N-Tosylpyrrole Derivatives, (2) Photochemistry of Heteroaromatic Fused ??-1,2,3-Triazoline Derivatives, (3) Application of Tetrazole Modified Calix[4]a." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/54411936287525538177.
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博士<br>國立交通大學<br>應用化學研究所<br>98<br>In part 1, the photolysis (230-325 nm) of N-tosyl pyrrole 37, 2-phenyl-N-tosyl pyrrole 72, 2,5-diphenyl-N-tosyl pyrrole 73, and N-(2-naphthyl)-sulfonyl pyrrole 75 in a 2-methyltetrahydrofuran glassy matrix at 4 K gives electron paramagnetic resonance (EPR) spectra with triplet characteristics; the zero-field-splitting (zfs) parameters D' for the corresponding radical pairs (RPs) 93, 94, 95, and 96 are 0.0239, 0.0190, 0.0174, and 0.0241 cm-1, respectively. Irradiation of 37 at RT allows the isolation of two rearranged products 38 and 39 and a polymeric material, which is consistent with cleavage of the N-S bond followed by recombination of RP 93. Triplet RPs 97, 98 obtained from the photolysis of N-tosylpyrrolosultine 24 and N-tosylpyrroloadduct 58, are stable at 77 K for at least 10 h. It is note worthy that the zfs parameters of triplet RPs 93-98 as well as their temperature and matrix dependencies are strikingly similar to those reported for triplet 3,4-dimethylene-N-tosylpyrrole biradicals 18, which possess same core structure. Furthermore, the X-ray crystallography also success proved the existence of RRs 95.
In part 2, the phenyl and quinoxaline fused ??-1,2,3-triazolines 186a and 186c were synthesized in good yields using Knoevenagel condensation and intramolecular 1,3-dipolar cycloaddition as two of the key reactions. Photolysis (254 nm light) of ??-1,2,3-triazolines 186a or 186c in acetonitrile led to the homolytic cleavage of nitrogen that generated diethyl diazomalonate 189, highly reactive intermediates aziridines 188a,c, and isoindoles B. The latter two species subsequently underwent rearrangement to give the nitrogen extrusion product 187a,c, and polymers. Furthermore, the reactive intermediates were trapped by dienophiles to give the corresponding cycloadducts. Subsequent rearrangement of the N-bridged cycloadducts gave N-substituted pyrrolo[3,4-b]quinoxaline 192c and 195c in 6% and 9% yields, respectively. Irradiation of 186a with fumaronitrile led to the isolation of cycloadduct 196a with retention of stereochemistry. Thermal reaction of 186c gave more nitrogen extruded product 187c than the photolysis did, which implied that zwitterionic intermediate might be involved in the former.
In part 3, calix[4]arenes 264a (R = OMe) and 264b (R = NO2) with 5,17-bis-p-substituted-phenylazo and 25,27-bis-oxymethyltetrazole groups were synthesized using the 1,3-dipolar cycloaddition of oxyacetonitrile azocalix[4]arenes 263a and 263b activated with trimethylsilyl azide, respectively. UV-vis screening of calix[4]arenes 264a and 264b with 14 metal ions showed that 264a (with p-methoxyphenylazo substituent) was a highly chromogenic sensor to Ca2+, while 364b (with p-nitrophenylazo substituent) showed color changes toward Ca2+, Ba2+, and Pb2+. Job plot experiments revealed a 1:1 binding stoichiometry for each of the complexes. The association constants for 264a•Ca2+, 264b•Ca2+, 264b•Ba2+, and 264b•Pb2+ were determined by Benesi-Hildebrand plots to be 9.1 ?e 104, 3.1 ?e 105, 1.1 ?e 105, and 1.6 ?e 105 M-1, respectively. Based on 1H NMR titration results, Ca2+ was bound to the two partially deprotonated hydroxyl azophenol groups and one of the two tetrazole groups of 264a and 264b.
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Lin, Chia-Hui, and 林佳慧. "Synthesis and Optimization of 2-(1-Ethyl-3,5-dimethyl-1H-pyrazol-4-yl)ethan-1-amine Derivatives with in Vitro Activity against Triple-Negative Breast Cancer Cells." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/77382163953235178318.
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碩士<br>國立中央大學<br>化學學系<br>104<br>Triple negative breast cancer (TNBC) has high mortality rate, high recurrence and high brain metastasis. Chemotherapy is the only treatment, and the worst of all it develops drug resistance. Therefore, we devote to drug discovery and synthesis for alleviating the suffering of patients.
According to the previous research, the derivatives of pyrazole scaffold have activity against cancer. Hence, we study pyrazole compound N-(2-(1-ethyl-3,5-dimethyl-1H-pyrazol-4-yl)ethyl)-4-isobutyl- N-methylbenzenesulfonamide (YL-18), which is chosen as the hit compound through high throughput screening approach in order to discover anti-cancer agent for treatment of TNBC. However, I don’t get desire compound (YL-18) through several synthetic routes, we change YL-18 to N-(2-(1-ethyl-3,5-dimethyl-1H- pyrazol-4-yl)ethyl)-4-isobutyl benzamide (YL-66).
The first generation compounds containing amine and amide bond of pyrazole derivatives was synthesized. We observed that pyrazole derivatives with amine group had better anti-cancer activity than amide group. In addition, the amine compounds don’t have the medium-dependent effect in the cytotoxic assay. The second generation compounds focused on several substituents at 4- position of benzene group. We found that there is no difference between electron withdrawing groups and electronic donating groups at benzene ring. Then, we compared hydrophobic substituents with hydrophilic substituents at C4 position of benzene ring; the results showed that compound YL-81 with hydrophobic substituents has better anti-cancer activity than others. In desire of the third generation compounds, we converted the secondary amine into tertiary amines, but they didn’t have enhancement of anti-cancer activity. In summary, compound YL-81 possesses potent anti proliferative activity against triple negative breast cancer MDA-MB-231 cells in DMEM and L15 medium with IC50 values of 9.76 and 0.5 µM, respectively.
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Smith, Emilie Despagnet. "Part I. Study of 1-acyl-2-dimethylphenylsilyl-2,3-dihydro-4-pyridone as synthetic intermediates ; Part II. Synthesis of enantiopure nicotine derivatives from nicotine." 2004. http://www.lib.ncsu.edu/theses/available/etd-07012004-172421/unrestricted/etd.pdf.
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Tsau, Yu-Shuo, та 曹育碩. "一、Lewis Acid-Promoted Intramolecular Cyclization of Silyl-Protected 3-(3-Arylpropargyltosylamino)methylcyclohex-2-en-1-ols: Synthesis of Azaspiro[4.5]dec-6-ene Derivatives 二、Brønsted Acid-Catalyzed and Lewis Acid-Assisted Intramolecular Cyclization of 2-Methyl-2,3-epoxy-4-(3-arylpropargyl)cyclohexan-1- ones: Synthesis of 7-Benzoylbicyclo[3.2.1]octan-2-one and Ar-yl(halo)methylenebicyclo[3.2.1]octan-2-one Derivatives". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/59021650894423613213.
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碩士<br>國立臺灣師範大學<br>化學系<br>102<br>This thesis focuses on acid-promoted intramolecular cyclization of O-silyl-protected 3-(3-arylpropargyltosylamino)methylcyclohex-2-en-1-ols and 2-methyl-2,3-epoxy-4-(3-arylpropargyl)cyclohexan-1-ones. Two major reactions are discussed. First, BF3•OEt2-promoted intramolecular cyclization/ fluorination of O-silyl-protected 3-(3-arylpropargyltosylamino)methylcyclo- hex-2-en-1-ols at room temperature under an atmosphere of nitrogen afforded N-containig spiro[4.5]dec-6-ene derivatives containing a C(sp2)-F bond. In this process, boron trifluoride diethyl etherate acts as both the Lewis Acid and the fluoride source. Second, TfOH-catalyzed cyclization of 2-methyl-2,3-epoxy- 4-(3-aryl-propargyl)cyclohexan-1-ones at room temperature under an atmosphere of nitrogen provided 7-benzoylbicyclo[3.2.1]octan-2-one. The Lewis Acid (FeCl3 or BF3•OEt2)-assisted cyclization of the same substrate in air at room temperature afforded aryl(halo)methylenebicyclo[3.2.1]octan-2-one de-rivatives containing a C(sp2)-halo bond (halo = Cl or F).
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Prince, Ashleigh Lauren. "Homogeneous and Heterogeneous Approaches to 1,2,4-Triazine-Accelerated Copper-Catalyzed Azide-Alkyne Cycloadditions." 2011. http://trace.tennessee.edu/utk_graddiss/1117.
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Over the last decade, the domain of click chemistry has grown exponentially and has significantly impacted the fields of organic synthesis, medicinal chemistry, molecular biology, and materials science. The ideal model of a click reaction has become the copper-catalyzed azide-alkyne cycloaddition (CuAAC). Inherent limitations of CuAAC, including high temperatures, long reaction times, and difficult purifications, have been minimized by the development of nitrogen-based ligands. Herein, we present a novel application of 1,2,4-triazines by investigating their use as accelerants for CuAAC.
A diverse library of 1,2,4-triazines were synthesized in order to examine the molecular determinants of their catalytic activity. These ligands were found to be potent accelerants, at catalytic concentrations, in the presence of both copper(I) and copper(II) salts. Remarkably, these catalyzed reactions proceeded at room temperature, generating high isolated yields, in both polar and nonpolar solvents. 5,6-Diphenyl-3-(pyridin-2-yl)1,2,4-triazine was the most active ligand studied, producing an 89% yield in a model click reaction within one hour. Additional experiments with an array of azides and alkynes yielded similar results, defining a broad substrate scope for 1,2,4-triazines as catalysts for click chemistry.
Heterogeneous 1,2,4-triazines were designed using different solid supports and different sites of attachment with respect to the 1,2,4-triazine ligand. The primary advantages offered by these immobilized catalysts are the prevention of metal contamination in 1,2,3-triazole products and the recyclability of the catalyst. Results indicated that 1,2,4-triazine-functionalized silica was a more effective accelerant of CuAAC, whereas polystyrene-supported 1,2,4-triazines displayed modest activity. In coordination with copper(II), 1,2,4-triazines appended onto silica generated isolated yields greater than 90% after four consecutive reaction cycles with minimal copper leaching. Further research will utilize both homogeneous and heterogeneous 1,2,4-triazine-accelerated CuAAC in the derivatization of solid supports for energy-related chemical processes and in the synthesis of novel enzyme inhibitors.
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Chaudhary, Arpana S. "Inhibitors of SecA as Potential Antimicrobial Agents." 2013. http://scholarworks.gsu.edu/chemistry_diss/77.
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Protein translocation is essential for bacterial survival and the most important translocation mechanism in bacteria is the secretion (Sec) pathway. Thus targeting Sec pathway is a promising strategy for developing novel antibacterial therapeutics.
We report the design, syntheses, mechanistic studies and structure-activity relationship studies using HQSAR and 3-D QSAR Topomer CoMFA analyses of 4-oxo-5-cyano thiouracil derivatives. In summary, introduction of polar group such as –N3 and linker groups such as –CH2-O- enhanced the potency as well as logP and logS several fold.
We also report the discovery, optimization and structure-activity relationship study of 1,2,4-triazole containing pyrimidines as novel, highly potent antimicrobial agents. A number of inhibitors have been found to inhibit microbial growth at high nanomolar concentrations.
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Yang, Fu-Ming, and 楊富名. "(1) Syntheses and Optical Resolution of Inherently Chiral Fluorescent Calix[4]arenes and Their Chiral Recognition (2) Syntheses of Calix[4]arenes with Lower-rim Anthryl-triazole and Ester Groups for Metal Ions Sensing Studies." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/33838972847607299254.
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碩士<br>國立交通大學<br>應用化學研究所<br>98<br>In this thesis, my research is focused on two topics. the first part is the synthesis and optical recognition of fluorescent inherently chiral calix[4]arenes and their chiral recognition. The second part is the synthesis of cailx[4]arenes with lower-rim triazole and ester groups as cationic binding site and anthracene as the fluorophores.
In part one, we synthesized novel calix[4]arene of AABH-type with inherent chirality through the reaction of racemic calix[4]arene derivatives 40a and 40b with 1-phenylethylamine (both R-form and S-form), follow by the separation of the diastereomers by column chromatography. Compounds 41-44 are optically pure inherently chiral calix[4]arenes. Based on the X-ray structure of 41, we could determine the absolute configurations of all three chiral cailx[4]arenes. We farther modified the lower-rim propargyl groups by Click Chemistry to add an anthracene groups as the fluorophores. The optically pure inherently chiral calyx[4]arenes were used for chiral recognition studies.
In second part, we synthesized a series of calix[4]arenes with lower-rim triazole and ester groups as the cationic binding sites, and anthracene as the fluorophores. When a cosolvent of methanol and chloroform (v/v = 99:1), both compound 49 and 51 have good selectivity toward Ag+ and Hg2+. Compared with 57, we confirmed that when thenumber of triazole and ester groups increased, their binding ability toward metal ions increased. The binding construct about 103~1010 (M-1).