Planar Chiral [2.2]Paracyclophane-Based Bisoxazoline Ligands: Design, Synthesis, and Use in Cu-Catalyzed Inter- and Intramolecular Asymmetric O–H Insertion Reactions
作者:Shinji Kitagaki、Shunsuke Murata、Kisaki Asaoka、Kenta Sugisaka、Chisato Mukai、Naoko Takenaga、Keisuke Yoshida
DOI:10.1248/cpb.c18-00519
日期:2018.10.1
insertion reactions of α-diazo esters. The reactivities and enantioselectivities of Cu complexes of the synthesized bisoxazoline ligands were lower than those of ligands without central chirality. However, planar chiral [2.2]paracyclophane-based bisoxazoline ligands with an inserted benzene spacer that had a sterically demanding isopropyl substituent showed good enantioselectivities in inter- and intramolecular
A highly efficient copper-catalyzed asymmetric carbenoidinsertion into O−H bonds of phenols has been realized by using chiral spiro bisoxazoline ligands, affording α-aryloxypropionates and the related propionic acids in high yields with excellent enantiomeric excesses.
Rapid and Efficient Synthesis of (<i>R</i>)-Aryloxypropionic Acid Esters Under Microwave Irradiation
作者:Zbigniew Ochal、Krzysztof Durka、Łukasz Banach
DOI:10.1080/00397910903395243
日期:2010.9.30
A series of (R)-(+)-ethyl aryloxypropionates (4a–4p) have been synthesized by the reaction of substituted phenols with ethyl (S)-(−)-tosyloxy lactate under the conditions of microwave irradiation and without solvents. The reaction conditions have been optimized. A good method for the preparation of (R)-(+)-ethyl aryloxypropionate was developed, with good yields, high enantiomer excess, short reaction
Organic compounds showing the ability to inhibit effector toxin secretion or translocation mediated by bacterial type III secretion systems are disclosed. The disclosed type III secretion system inhibitor compounds are useful for combating infections by Gram-negative bacteria such as
Salmonella
spp.,
Shigella flexneri, Pseudomonas
spp.,
Yersinia
spp., enteropathogenic and enteroinvasive
Escherichia coli
, and
Chlamydia
spp. having such type III secretion systems.