A compound represented by general formula (1) (wherein R
1
represents a hydrogen atom, an optionally substituted C
1-6
alkyl group or the like; R
2
represents a hydrogen atom, an optionally substituted C
1-6
alkyl group or the like; R
3
represents a hydrogen atom or an optionally substituted C
1-6
alkyl group; R
4
represents a hydrogen atom, an optionally substituted C
1-6
alkyl group or the like; X
1
represents an optionally substituted C
2-6
alkynylene group or the like; A represents an optionally substituted bivalent aromatic hydrocarbon group or the like; X
2
represents an optionally substituted C
1-6
alkylene group or the like; Y
1
represents an oxygen atom or the like; and R
5
represents a hydrogen atom or the like) or a salt thereof is useful as an antibacterial agent.
Macromolecular helicity inversion of an optically active helical poly(phenylacetylene) by chemical modification of the side groups
作者:Shinzo Kobayashi、Kazuhide Morino、Eiji Yashima
DOI:10.1039/b701281k
日期:——
An optically active helical poly(phenylacetylene) was synthesized by the copolymerization of phenylacetylenes bearing optically active hydroxy or ester groups obtained by the kinetic resolution of a racemic phenylacetylene with lipase; the helix-sense was inverted from one helix to another by the further chemical modification of the hydroxy groups with achiral bulky isocyanates or an acid chloride.
Investigation of asymmetric alcohol dehydrogenase (ADH) reduction of acetophenone derivatives: effect of charge density
作者:Hemantkumar G. Naik、Bahar Yeniad、Cor E. Koning、Andreas Heise
DOI:10.1039/c2ob06870b
日期:——
study the effect of substituent groups of the substrate on the alcoholdehydrogenase (ADH) reductions of aryl–alkyl ketones, several derivatives of acetophenone have been evaluated against ADHs from Lactobacillus brevis (LB) and Thermoanaerobacter sp. (T). Interestingly, ketones with non-demanding (neutral) para-substituents were reduced to secondaryalcohols by these enzymes in enantiomerically pure form
Click-Connected Ligand Scaffolds: Macrocyclic Chelates for Asymmetric Hydrogenation
作者:Qing Zhang、James M. Takacs
DOI:10.1021/ol702890s
日期:2008.2.1
Click chemistry is used to construct ligand scaffolds for a series of chiral diphosphites. Enantioselectivity as high as 97% ee is obtained using these click ligands in rhodium-catalyzed asymmetric hydrogenation. Control experiments and spectroscopic data suggest that a 16-membered PP-macrocyclic Rh(I) chelate is formed.