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.
Diastereoselective α-alkoxylation of lactamide N-alkyl groups via intramolecular formation of oxonium ions as the key intermediate
作者:Tohru Kamada、Akira Oku
DOI:10.1039/a805638b
日期:——
Stereoselective introduction of an alkoxy group to the amine unit of lactamide derivatives, under electrochemical oxidation conditions, was investigated based upon the assumption that a cyclic oxonium ion can be formed between the alkoxy substituent on the chiral center and a carbocation generated at the α-position of N-alkyl substituents. With N-monosubstituted lactamides, diastereoselectivity in the N-α-alkoxylated product was not observed. With N,N-disubstituted lactamides, however, the selectivity appeared though in low ratios (â2.2). Requisite factors that govern the stereoselectivity, i.e. nucleophilicity of both internal and external nucleophiles and substitution on amine units, were also examined.