Fig. 13. (a) Proposed model for highly site-selective C-4 acylation of glucopyranoside primarily via catalyst interaction with C-6 hydroxyl. (b) Details of site selectivity comparing catalyst A and DMAP as well as the effect of methylating the C-6 hydroxyl. (c) Total synthesis of multifidoside B through selective final step acylation in the presence of two primary hydroxyl groups.
