Three-Component Staudinger-Type Stereoselective Synthesis of C-Glycosyl-p-lactams and their Use as Precursors for C-Glycosyl Isoserines and Dipeptides.A Polymer-Assisted Solution-Phase Approach

摘要

A collection of 4-(C-galactosyl)- and 4-(C-ribosyl)-beta-lactams featuring different substituents at C-3 and N-l was prepared by combining in a one-pot procedure a formyl C-glycoside,a primary amine,and a substituted acetyl chloride in the presence of base (Staudinger-type reaction).Sulfonyl chloride and aminomethylated resins were used m sequence to remove excess of components and by-products.Two pure C-glycosyl-beta-lactams were effectively transformed into C-glycosyl-N-Boc-beta-amino-a-hydroxy esters (C-glycosyl isoserines) and a C-ribosyl dipeptide via base-promoted heterocycle ring opening by meth-anol and L-phenylalanine methyl ester,respectively.