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Academic literature on the topic 'Phenanthroline-1,10(bis-(methyl-4 phenyl)-2,9)'
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Journal articles on the topic "Phenanthroline-1,10(bis-(methyl-4 phenyl)-2,9)"
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Li, Peng-Peng, Li Zhao, Ji-Xing Zhao, Zhao-Bin Zhu, Fei Wang, and Qin-Qin An. "Synthesis and crystal structure of bis{1-(((4-(1-(hydroxyimino)ethyl)phenyl)imino)methyl)naphthalen-2-olato-κ2O,N}copper(II), C38H30CuN4O4." Zeitschrift für Kristallographie - New Crystal Structures 232, no. 6 (November 27, 2017): 889–90. http://dx.doi.org/10.1515/ncrs-2017-0044.
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AbstractC38H30CuN4O4, triclinic, P1̅ (no. 2), a = 8.3882(7) Å, b = 8.5024(9) Å, c = 11.3649(15) Å, α = 89.960(10)°, β = 69.689(10)°, γ = 80.269(8)°, Z = 1, V = 747.73(15) Å3, Rgt(F) = 0.0701, wRref(F2) = 0.1308, T = 294.68(10) K.
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Zang, Kai-Kai, Xiao Xiao, Li-Qiang Chen, Yan Yang, Qi-Lai Cao, Yu-Long Tang, Su-Su Lv, Hong Cao, Ling Zhang, and Yu-Qiu Zhang. "Distinct Function of Estrogen Receptors in the Rodent Anterior Cingulate Cortex in Pain-related Aversion." Anesthesiology 133, no. 1 (April 22, 2020): 165–84. http://dx.doi.org/10.1097/aln.0000000000003324.
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Background Brain-derived estrogen is implicated in pain-related aversion; however, which estrogen receptors mediate this effect remains unclear. This study hypothesized that the different estrogen receptors in the rostral anterior cingulate cortex play distinct roles in pain-related aversion. Methods Formalin-induced conditioned place avoidance and place escape/avoidance paradigms were used to evaluate pain-related aversion in rodents. Immunohistochemistry and Western blotting were used to detect estrogen receptor expression. Patch-clamp recordings were used to examine N-methyl-d-aspartate–mediated excitatory postsynaptic currents in rostral anterior cingulate cortex slices. Results The administration of the estrogen receptor-β antagonist 4-(2-phenyl-5,7-bis [trifluoromethyl] pyrazolo [1,5-a] pyrimidin-3-yl) phenol (PHTPP) or the G protein–coupled estrogen receptor-1 antagonist (3aS*,4R*,9bR*)-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-3H-cyclopenta [c] quinolone (G15) but not the estrogen receptor-α antagonist 1,3-bis (4-hydroxyphenyl)-4-methyl-5-[4-(2-piperidinylethoxy) phenol]-1H-pyrazole dihydrochloride (MPP) into the rostral anterior cingulate cortex blocked pain-related aversion in rats (avoidance score, mean ± SD: 1,3-bis [4-hydroxyphenyl]-4-methyl-5-(4-[2-piperidinylethoxy] phenol)-1H-pyrazole dihydrochloride (MPP): 47.0 ± 18.9%, 4-(2-phenyl-5,7-bis [trifluoromethyl] pyrazolo [1,5-a] pyrimidin-3-yl) phenol (PHTPP): −7.4 ± 20.6%, and [3aS*,4R*,9bR*]-4-[6-bromo-1,3-benzodioxol-5-yl]-3a,4,5,9b-3H-cyclopenta [c] quinolone (G15): −4.6 ± 17.0% vs. vehicle: 46.5 ± 12.2%; n = 7 to 9; P < 0.0001). Consistently, estrogen receptor-β knockdown but not estrogen receptor-α knockdown by short-hairpin RNA also inhibited pain-related aversion in mice (avoidance score, mean ± SD: estrogen receptor-α–short-hairpin RNA: 26.0 ± 7.1% and estrogen receptor-β–short-hairpin RNA: 6.3 ± 13.4% vs. control short-hairpin RNA: 29.1 ± 9.1%; n = 7 to 10; P < 0.0001). Furthermore, the direct administration of the estrogen receptor-β agonist 2,3-bis (4-hydroxyphenyl)-propionitrile (DPN) or the G protein–coupled estrogen receptor-1 agonist (±)-1-([3aR*,4S*,9bS*]-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta [c]quinolin-8-yl)-ethanone (G1) into the rostral anterior cingulate cortex resulted in conditioned place avoidance (avoidance score, mean ± SD: 2,3-bis (4-hydroxyphenyl)-propionitrile (DPN): 35.3 ± 9.5% and (±)-1-([3aR*,4S*,9bS*]-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta [c]quinolin-8-yl)-ethanone (G1): 43.5 ± 22.8% vs. vehicle: 0.3 ± 14.9%; n = 8; P < 0.0001) but did not affect mechanical or thermal sensitivity. The activation of the estrogen receptor-β/protein kinase A or G protein–coupled estrogen receptor-1/protein kinase B pathway elicited the long-term potentiation of N-methyl-d-aspartate–mediated excitatory postsynaptic currents. Conclusions These findings indicate that estrogen receptor-β and G protein–coupled estrogen receptor-1 but not estrogen receptor-α in the rostral anterior cingulate cortex contribute to pain-related aversion by modulating N-methyl-d-aspartate receptor–mediated excitatory synaptic transmission. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New
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Ma, Jin-Xia, Qing-Lin Li, Peng-Peng Li, Ji-Xing Zhao, and Li Zhao. "Crystal structure of bis{5-methoxy-2-((E)-((4-((E)-1-(methoxyimino)ethyl)phenyl)imino)methyl)phenolato-κ2N,O}nickel(II), C34H34N4NiO6." Zeitschrift für Kristallographie - New Crystal Structures 233, no. 5 (August 28, 2018): 767–69. http://dx.doi.org/10.1515/ncrs-2017-0379.
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AbstractC34H34N4NiO6, monoclinic, P21/c (no. 14), a = 10.5538(5) Å, b = 6.1691(2) Å, c = 24.2831(9) Å, β = 100.519(4)°, Z = 2, V = 1554.43(11) Å3, Rgt(F) = 0.0402, wRref(F2) = 0.0973, T = 294.39(10) K.
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Zhang, Zi-Yang, Zhen-Zhong Huang, Yang Pan, and Cheng Song. "New transparent and thermally stable cardo poly(ether imide)s derived from 10,10-bis[4-(4-amino-2-pyridinoxy)phenyl]-9(10H)-anthrone." High Performance Polymers 32, no. 5 (October 23, 2019): 483–93. http://dx.doi.org/10.1177/0954008319883005.
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A new diamine bearing flexible ether, rigid pyridine, and bulky anthrone pendent group, 10,10-bis[4-(4-amino-2-pyridinoxy)phenyl]-9(10 H)-anthrone (BAPPA), was prepared in three steps from anthrone. BAPPA was reacted with six conventional aromatic dianhydrides in N, N-dimethylacetamide (DMAc) to form the corresponding new poly(ether imide)s (PEIs) via the poly(ether amic acid) (PEAA) precursors with inherent viscosities ranging from 0.85 dL g−1 to 1.26 dL g−1 and thermal imidization. All the PEAAs could be cast from DMAc solution and thermally converted into transparent, flexible, and tough PEI films with tensile strength of 72.2–112.4 MPa, tensile modulus of 1.8–2.1 GPa, and elongation at break of 10–18%. These PEIs were predominantly amorphous and displayed excellent thermal stability with the glass transition temperature of 290–388°C, the 5% weight loss temperature of 480–514°C, and the residue of 68–43% at 800°C in nitrogen. The PEIs derived from 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride and 4,4′-hexafluoroisopropylidenediphathalic anhydride exhibited excellent solubility in organic solvents such as N-methyl-2-pyrrolidinone, DMAc, N, N-dimethylformamide, pyridine, and even in tetrahydrofuran. Meanwhile, these PEIs also exhibited high optical transparency with the ultraviolet cutoff wavelength in the 374–427 nm range and the wavelength of 80% transparency in the range of 468–493 nm.
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Krečmerová, Marcela, Hubert Hřebabecký, Milena Masojídková, and Antonín Holý. "Synthesis of 5-Phenyl-2(1H)-pyrimidinone Nucleosides." Collection of Czechoslovak Chemical Communications 61, no. 3 (1996): 458–77. http://dx.doi.org/10.1135/cccc19960458.
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Reaction of 2-phenyltrimethinium salt 1 with thiourea and subsequent reaction with chloroacetic acid afforded 5-phenyl-2(1H)-pyrimidinone (3). Its silyl derivative 4 was condensed with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose under catalysis with tin tetrachloride or trimethylsilyl trifluoromethanesulfonate to give protected nucleoside 5 together with 5',O6-cyclo-5-phenyl-1,3-bis- (β-D-ribofuranosyl)-6-hydroxy-5,6-dihydro-2(1H,3H)-pyrimidinone (7). The greatest amounts of 7 were formed with the latter catalyst. Nucleosidation of the silyl derivative 4 with protected methyl 2-deoxy-D-ribofuranoside 8 or 2-deoxy-D-ribofuranosyl chloride 9 afforded 1-(2-deoxy-3,5-di-O-p-toluoyl-β-D-ribofuranosyl)-5-phenyl-2(1H)-pyrimidinone (10) and its α-anomer 11. Reaction of 10 and 11 with methanolic ammonia gave free 2'-deoxynucleosides 12 and 13. Compound 13 was converted into 5'-O-tert-butyldiphenylsilyl-3'-O-mesyl derivative 14 which on heating with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and subsequent cleavage with tetrabutylammonium fluoride afforded 2',3'-dideoxy-2',3'-didehydronucleoside 15. Reaction of the silyl derivative 4 with 1,2-di-O-acetyl-3,5-di-O-benzoylxylofuranose (18), catalyzed with tin tetrachloride, furnished 1-(2-O-acetyl-3,5-di-O-benzoyl-β-D-xylofuranosyl)-2(1H)-pyrimidinone (19) which was deprotected to give the β-D-xylofuranosyl derivative 22. As a side product, the nucleosidation afforded the β-D-xylopyranosyl derivative 23. Deacetylation of compound 19 gave 1-(3,5-di-O-benzoyl-β-D-xylofuranosyl)-5-phenyl-2(1H)-pyrimidinone (24) which on reaction with thionyl chloride afforded 2'-chloro-2'-deoxynucleoside 25 and 2',O6-cyclonucleoside 26. Heating of compound 25 with DBU in dimethylformamide furnished the lyxo-epoxide 27 which on reaction with methanolic ammonia was converted into free 1-(2,3-anhydro-β-D-lyxofuranosyl)-5-phenyl-2(1H)-pyrimidinone (28). Reaction of 1,2-di-O-acetyl-5-O-benzoyl-3-O-methanesulfonyl-D-xylofuranose (30) with silyl derivative 4 gave the nucleoside 31 which by treatment with DBU was converted into an equilibrium mixture of 5'-benzoylated arabinofuranoside 33a and its 2',6-anhydro derivative 33b.
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Zhou, Yu-Ting, Shou-Ri Sheng, Chuan-Chao Tang, Cheng Song, Zhen-Zhong Huang, and Xiao-Ling Liu. "Preparation and characterization of novel soluble polyarylates derived from 9,9-bis[4-(4-chloroformylphenoxy)phenyl]xanthene with various bisphenols." High Performance Polymers 30, no. 10 (November 30, 2017): 1203–9. http://dx.doi.org/10.1177/0954008317744869.
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A series of new polyarylates bearing cardo xanthene groups were synthesized by phase-transfer-catalyzed interfacial polycondensation of 9,9-bis[4-(4-chloroformylphenoxy)phenyl]xanthene with various bisphenols containing the isopropylidene, hexafluoroisopropylidene, 1-phenylethylidene, diphenylmethane, cyclohexane, and xanthene structures. High-molecular-weight polyarylates with number-average molecular weight and polydispersity index in the range of 30,100–35,300 and 1.82–2.17, respectively, exhibited high glass transition temperatures ranged from 226°C to 261°C, and their 10% weight loss temperatures were in the range of 421–452°C with char yields above 45% at 700°C in nitrogen. All the polyarylates were amorphous and readily soluble in organic solvents such as dichloromethane, chloroform, tetrahydrofuran, meta-cresol, pyridine, N,N-dimethylformamide, N,N-dimethylacetamide, and 1-methyl-2-pyrrolidinone at room temperature and could be cast into tough, transparent, and flexible films with tensile strengths of 85.6–108.3 MPa, elongations at break of 2–3%, and tensile moduli of 7–9 GPa.
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Luo, Yi-Sheng, Qiu-Ying Wang, Xue-Chun Mao, and Shou-Ri Sheng. "Synthesis and characterization of new cardo poly(ether amide)s containing 9(10H)-anthrone units." High Performance Polymers 32, no. 9 (May 11, 2020): 1001–9. http://dx.doi.org/10.1177/0954008320918922.
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A new aromatic diamine, 10,10-bis[4-(4-aminophenoxy)phenyl]-9(10 H)-anthrone (BAPA) has been synthesized from anthrone via three-step procedure. Direct phosphorylation polycondensation of BAPA with various aromatic dicarboxylic acids produced a series of cardo poly(ether amide)s with inherent viscosities of 0.97–1.29 dL g−1. All the polymers were readily soluble in polar solvents such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide (DMAc), and pyridine at room temperature, and afforded transparent, strong, and flexible films upon casting from DMAc solvent. The resulting poly(ether amide)s had glass transition temperatures of 254–316°C, 10% weight loss temperatures of 495–524°C, and char yields of 55–70% at 800°C in nitrogen. These polymers were amorphous and their films exhibited tensile strengths of 81.6–104.7 MPa, tensile moduli of 1.8–2.4 GPa, and elongations at break of 8–15%.
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Ghorab, Mostafa M., Mansour S. Al-Said, and Reem K. Arafa. "Design, Synthesis and Potential Anti-Proliferative Activity of Some Novel 4-Aminoquinoline Derivatives." Acta Pharmaceutica 64, no. 3 (September 1, 2014): 285–97. http://dx.doi.org/10.2478/acph-2014-0030.
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Abstract Novel nineteen compounds based on a 4-aminoquinoline scaffold were designed and synthesized as potential antiproliferative agents. The new compounds were N-substituted at the 4-position by aryl or heteroaryl (1-9), quinolin- 3-yl (10), 2-methylquinolin-3-yl (11), thiazol-2-yl (12), and dapsone moieties (13, 14 and 18). Bis-compounds 15, 16 and 19 were also synthesized to assess their biological activity. All the newly synthesized comounds were tested for in vitro antiproliferative activity against the MCF-7 breast cancer cell line. Seventeen of the novel compounds showed higher activity than the reference drug doxorubicin. The corresponding 7-(trifluoromethyl)-N-(3,4,5-trimethoxyphenyl)quinolin-4- amine 1, N-(7-(trifluoromethyl)quinolin-4-yl)quinolin- 3- amine (10), 2-methyl-N-(7-trifluorome-thyl)quinolin-4-yl) quinolin-3-amine (11) and N-(4-(4-aminophenylsulfonyl) phenyl)-7-chloroquinolin-4-amine (13) were almost twice to thrice as potent as doxorubicin. Biological screening of the tested compounds could offer an encouraging framework in this field that may lead to the discovery of potent anticancer agents.
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Weni, Mustika, Mega Safithri, and Djarot Sasongko Hami Seno. "Molecular Docking of Active Compounds Piper crocatum on the A-Glucosidase Enzyme as Antidiabetic." Indonesian Journal of Pharmaceutical Science and Technology 7, no. 2 (July 11, 2020): 64. http://dx.doi.org/10.24198/ijpst.v7i2.21120.
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Ethanol extract of Piper crocatum leaves has inhibitory activity of α-glucosidase enzyme. Ethyl acetate fraction from Piper crocatum leaves has the highest antioxidant activity. Previous research has provided information that the ethyl acetate fraction of Piper crocatum leaves has an inhibition of α-glucosidase containing 6XO32ZSP1D, Ethyl L-serinate hydrochloride compound, Schisandrin B compound, Columbin compound, 4- (4-methoxy-phenylamino) -2 compound, 3-dihydro-1H-4a, 9-diazacyclopenta (b) fluorine-10-carbonitrile, compound 6-Amino-4- [3- (benzyloxy) phenyl] -3-tert-butyl-2,4-dihydropyrano [2, 3-c] pyrazole-5-carbonitrile, compound 4 - {{4.6-Bis [(3R, 5S) -3,5-diamino-1-piperydinyl] -1,3,5-triazine-2-yl} amino) benzenesulfonamide and compound 1.1 '- (1,4-butanediyl) bis {2,6-dimethyl-4 - [(3-methyl-1,3-benzothiazol-2 (3H) ylidene) methyl] pyridinium. This study aims to study the interaction between bioactive compounds contained in ethyl acetate fraction of Piper crocatum leaves with α-glucosidase enzyme in In Silico using AutoDock Vina, Columbin shows the lowest binding energy with binding sites with amino acids Ser240, Asp242, His280, Arg315, Glu411, Phe159, Arg442, Tyr158 and Phe303. Columbin has the stability and inhibits the α-glucosidase enzyme from S. cerevisiae better than the seven other compounds, because it has OH and CH3 groups which play a role in the interaction with around the active side of the α-glucosidase enzyme.Keywords: Columbin, In Silico, α-Glucosidase
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Bertolasi, V., P. Gilli, V. Ferretti, and G. Gilli. "Intermolecular N-H...O Hydrogen Bonding Assisted by Resonance. II. Self Assembly of Hydrogen-Bonded Secondary Enaminones in Supramolecular Catemers." Acta Crystallographica Section B Structural Science 54, no. 1 (February 1, 1998): 50–65. http://dx.doi.org/10.1107/s0108768197008677.
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The crystal structures of 15 compounds containing the 2-en-3-amino-1-one heterodienic system and forming intermolecular N—H...O hydrogen bonds assisted by resonance (RAHB) are reported: (1) 3-phenylamino-2-cyclohexen-1-one; (2) 3-(4-methoxyphenylamino)-2-cyclohexen-1-one; (3) 3-(4-chlorophenylamino)-2-cyclohexen-1-one; (4) 3-(4-methoxyphenylamino)-2-methyl-2-cyclohexen-1-one; (5) 3-(4-methoxyphenylamino)-5-methyl-2-cyclohexen-1-one; (6) 3-isopropylamino-5,5-dimethyl-2-cyclohexen-1-one; (7) 3-phenylamino-5,5-dimethyl-2-cyclohexen-1-one; (8) 3-(3-methoxyphenylamino)-5,5-dimethyl-2-cyclohexen-1-one; (9) N,N-3-aza-pentane-1,5-bis[1-(3-oxo-5,5-dimethyl-1-cyclohexenyl)]; (10) 3-phenylamino-6,6-dimethyl-2-cyclohexen-1-one; (11) 3-(2-methoxyphenylamino)-6,6-dimethyl-2-cyclohexen-1-one; (12) 3-(3-chlorophenylamino)-6,6-dimethyl-2-cyclohexen-1-one; (13) 3-(4-chlorophenylamino)-6,6-dimethyl-2-cyclohexen-1-one; (14) 1-(4-chlorophenyl)-4-(4-chlorophenylamino)-6-methyl-2-pyridone; (15) 3-(4-chlorophenylamino)-5-phenyl-2-cyclopenten-1,4-dione. All compounds form intermolecular N—H...O=C hydrogen bonds assisted by resonance connecting the heteroconjugated enaminonic groups in infinite chains. Chain morphologies are analyzed to find out crystal engineering rules able to predict and interpret the crystal packing. Simple secondary enaminones [i.e. (1)–(13) together with a number of structures retrieved from the Cambridge Structural Database] are found to form hydrogen bonds having π-delocalizations, as characterized by a C=O bond-length average of 1.239 ± 0.004 Å, and hydrogen-bond strengths, represented by the N...O average distance of 2.86 ± 0.05 Å, very similar to those previously found for amides. Enaminones, however, can be easily substituted by chemical groups able to influence both π-conjugations and N...O hydrogen-bond distances. Some substituted enaminones, retrieved from the literature, display, in fact, N...O hydrogen-bond distances as short as 2.627 Å and large π-delocalizations with C=O double-bond distances as long as 1.285 Å. These effects appear to be associated with (a) the presence of further π-conjugated systems involving the C=O and NH groups of the enaminone moiety or (b) the transformation of the enaminone carbonyl group in an amidic function.
Book chapters on the topic "Phenanthroline-1,10(bis-(methyl-4 phenyl)-2,9)"
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Taber, Douglass F. "The Snyder Synthesis of Psylloborine A." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0099.
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In addition to the monomeric coccinellid alkaloids produced by the ladybug, some dimeric alkaloids, exemplified by psylloborine A 3, have been isolated. Scott A. Snyder of Scripps/Florida initially attempted a direct dimerization strategy for the assembly of 3, but when that failed, he devised (J. Am. Chem. Soc. 2014, 136, 9743) a route to the tethered dimer 1, that could indeed be cyclized to 2, the immediate precursor to 3. The starting material for both 9, the lower half of 1, and 13, the upper half of 1, was the commercial, enantiomerically-pure piperidine 4. Metalation followed by allylation gave the desired trans diastereomer 5. Oxidative cleavage followed by condensation with 6 gave the ester 7, that was hydrogenated, then converted with 8 to the desired phosphonate 9. To prepare 13, 4 was metalated and alkylated with methallyl bromide. The product 10 was carried on to the enone 12 by oxidative cleavage followed by the addition of 11, oxidative cleavage, and dehydration. Reduction to the desired diastereomer was achieved by conjugate addition of hydride in the presence of the sterically very demanding Yamamoto Lewis acid ATPH. Deprotection followed by oxidation then gave 13, that was condensed with 9 and deprotected to give 14. Selective deprotection followed by oxidation and condensation with 15 then led to 1. A key element in the design of this synthesis was the ability to easily tune the sulfone activating group, to direct the proper order of bond formation. The vision was that regeneration of the enone and deprotection, with tetramethylguanidine, would lead to 16. The free amine would add to the saturated ketone to give an enamine, that would in turn add in a conjugate sense to the enone to give 17. Further deprotection of 17 under acid conditions would again generate an enamine that, it was hoped, would, after further cyclization, add to the unsaturated sulfone to give 2. As illustrated, the 3,5-bis(trifluoromethyl)phenyl sulfone gave the best results. Desulfurization of 2 completed the synthesis of the complex dimeric alkaloid psylloborine A 3.
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Taber, Douglass. "The Burke Synthesis of ( + )-Didemniserinolipid B." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0088.
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The sulfate ( + )-didemniserinolipid B 3, isolated from the tunicate Didemnum sp, has an intriguing spiroether core. A key step in the synthesis of 3 reported (Organic Lett. 2007, 9, 5357) by Steven D. Burke of the University of Wisconsin was the selective ring-closing metathesis of 1 to 2. The diol 6 that was used to prepare the ketal 1 was readily prepared from the inexpensive D-mannitol 4. Many other applications can be envisioned for the enantiomerically-pure diol 6 and for the monoacetate and bis acetate that are precursors to it. To set up the metathesis, the β, γ-unsaturated ketone 10 was needed. To this end, the keto phosphonate derived from the addition of the phosphonate anion 8 to the lactone 7 was condensed with phenyl acetaldehyde 9. The derived enone 10 was a 5:1 mixture of β, γ- and α, β-regioisomers. The diol 6 is C2 -symmetrical, but formation of the ketal 1 dissolved the symmetry, with one terminal vinyl group directed toward the styrene double bond, and the other directed away from it. On exposure to the first generation Grubbs catalyst, ring formation proceeded efficiently, to give 2. Williamson coupling with the serine-derived alcohol 11 then gave 12. To establish the secondary alcohol of 13 and so of 3, the more electron rich alkene of 12 was selectively epoxidized, from the more open face. Diaxial opening with hydride then gave 13. With 13 in hand, another challenge of selectivity emerged. The plan had been to attach the ester-bearing sidechain to 13 using alkene metathesis, then hydrogenate. As the side-chain of 3 contained an additional alkene, this had to be present in masked form. To this end, the α-phenylselenyl ester 14 was prepared. Alkene metathesis with 13 proceeded smoothly, this time using the second generation Grubbs catalyst. The unwanted alkene was then removed by reduction with diimide, and the selenide was oxidized to deliver the α, β-unsaturated ester.
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Taber, Douglass F. "Substituted Benzenes: The Garg Synthesis of Tubingensin A." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0062.
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John F. Hartwig of the University of California, Berkeley devised (Science 2014, 343, 853) conditions for the regioselective silylation of an arene 1 to give 2. The silyl group can directly be converted, inter alia, to halo, amino, alkyl, or hydroxyl. Jin-Quan Yu of Scripps La Jolla effected (Angew. Chem. Int. Ed. 2014, 53, 2683) regioselective alkenylation of the arene 3 with 4 to give 5. Wei-Liang Duan of the Shanghai Institute of Organic Chemistry described (Org. Lett. 2014, 16, 500) a related alkenylation protocol. Deping Wang of Henyang Normal University developed (Eur. J. Org. Chem. 2014, 315) inexpensive conditions for the conversion of an aryl bromide 6 to the corresponding phenol 7. Mamoru Tobisu and Naoto Chatani of Osaka University used (J. Am. Chem. Soc. 2014, 136, 5587) a Ni catalyst to convert the lactam 8 to the aryl boronate 9. Patrick J. Walsh of the University of Pennsylvania found (Adv. Synth. Catal. 2014, 356, 165) conditions for the clean monoarylation of the amide 11 with 10 to give 12. In an application of the Catellani approach, Zhi- Yuan Chen of Jiangxi Normal University coupled (Chem. Eur. J. 2014, 20, 4237) the aryl iodide 13 with 14 to give the amino ester 15. Frederic Fabis of the Université de Caen-Basse-Normandie used (Chem. Eur. J. 2014, 20, 7507) Pd to catalyze the ortho halogenation (and alkoxylation) of the N-sulfonylamide 16 to give 17. Wen Wan of Shanghai University and Jian Hao of Shanghai University and the Shanghai Institute of Organic Chemistry effected (Chem. Commun. 2014, 50, 5733) ortho azidination of the aniline 18 with 19, leading to 20. Jianbo Wang of Peking University found (Angew. Chem. Int. Ed. 2014, 53, 1364) that the N-aryloxy amide 21 could be combined with the α-diazo ester 22 to give the ortho-alkenyl phenol 23. Silas P. Cook of Indiana University uncovered (Org. Lett. 2014, 16, 2026) remarkably simple conditions for the enantiospecific cyclization of 24 (65% ee) to 25 (63% ee). The development of arynes as reactive intermediates continues unabated. Xiaoming Zeng of Xi’an Jiaotong University developed (Org. Lett. 2014, 16, 314) the reagent 27 for the bis-functionalization of the aryne derived from 26.
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Taber, Douglass F. "Organic Functional Group Protection and Deprotection." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0016.
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Corey R. J. Stephenson of Boston University devised (Chem. Commun. 2011, 47, 5040) a protocol using visible light for removing the PMB group from 1 to give 2. John F. Hartwig, now at the University of California, Berkeley, developed (Science 2011, 332, 439) a Ni catalyst for the cleavage of the durable aryl ether of 3 to give 4. Mark S. Taylor of the University of Toronto devised (J. Am. Chem. Soc. 2011, 133, 3724) the catalyst 6, which selectively mediated esterifi cation of 5 to 7. Jean-Marie Beau of the Université Paris-Sud added (Chem. Commun. 2011, 47, 2146) Et3 SiH following the Fe-catalyzed deprotection-protection of 8, resulting in clean conversion to the bis ether 9. Mahmood Tajbakhsh of the University of Mazandaran showed (Tetrahedron Lett. 2011, 52, 1260) that guanidine HCl catalyzed the conversion of 10 to 11. Stephen W. Wright of Pfizer/Groton established (Tetrahedron Lett. 2011, 52, 3171) that the new urethane protecting group of 12, stable to many conditions, could be deprotected to 13 under conditions that spared even a Boc group. Matthias Beller of the Leibniz-Institute for Catalysis protected (Chem. Commun. 2011, 47, 2152) the amine 14 as the readily hydrolyzed imidazole 16. Sentaro Okamoto of Kanagawa University found (Org. Lett. 2011, 13, 2626) a simple reagent combination for the removal of the sometimes reluctant sulfonamide from 17. Jordi Burés and Jaume Vilarrasa of the Universitat de Barcelona removed (Angew. Chem. Int. Ed. 2011, 50, 3275) the oxime from 19 by Au-catalyzed exchange with 20. Pengfei Wang of the University of Alabama, Birmingham, designed (J. Org. Chem. 2011, 76, 2040) a range of photochemically removable protecting groups for aldehydes and ketones. Rafael Robles of the University of Granada selectively protected (J. Org. Chem. 2011, 76, 2277) the diol 24 using the reagent created by the activation of 25. Berit Olofsson of Stockholm University prepared (Org. Lett. 2011, 13, 3462) the phenyl ester 28 by exposing 27 to the diaryl iodonium triflate. Kannoth Manheri Muraleedharan of the Indian Institute of Technology, Madras, selectively (Org. Lett. 2011, 13, 1932) esterified 29 to 30 with catalytic SmCl3.