Pilocarpine (1) was synthesized in seven steps starting from 2-acetylbutyrolactone. Chirality was introduced by asymmetric reduction of enone 4 and transferred via a Claisen rearrangement. A mild procedure for the preparation of 1,5-disubstituted imidazoles in the last synthetic operation led to pilocarpine unaccompanied by isopilocarpine.
Asymmetric total synthesis of syringolide 1, a nonproteinaceous elicitor
作者:Jun Ishihara、Tetsuya Sugimoto、Akio Murai
DOI:10.1016/s0040-4020(97)10062-x
日期:1997.11
An asymmetric synthesis of syringolide 1, one of the elicitors produced by Pseudomonas syringae pv. tomato, is described. It was synthesized from 2-(1-oxoethyl)-2-buten-4-olide via 1,4-addition of alkenyl cuprate, asymmetric dihydroxylation, and intramolecular Michael reaction.
Process for preparing 2,2-difluoroethylamine derivatives, wherein compounds of the general formula (IV) are reduced to the corresponding 2,2-difluoroethylamine derivatives of the general formula (III), where the A radical is as defined in the description: