Synthesis of C-Glycosyl Lactones and Protected C-Glycosyl Amino Acids: Use of Radical Cyclization.
Protected carbohydrates 6a-13a, having one free hydroxyl and a phenylseleno group or halogen on the adjacent carbon, were condensed with (2,2-diphenylhydrazono)acetic acid (2); the resulting esters undergo radical cyclization to afford carbohydrates fused to a 2,2-diphenylhydrazino lactone unit (6c,d-13c,d). In suitable cases (9c,d) such carbohydrate lactones can be elaborated into C-glycosyl amino acids.
Zhang
Junhu
J
Chemistry Department, University of Alberta, Edmonton, Alberta, Canada T6G 2G2.
Clive
Derrick L. J.
DL