The Reactivity on Acetylation of Hydroxyl Groups in Grayanotoxin III

Abstract

Rates of acetylation of hydroxyl groups in Grayanotoxin (G)III were measured to investigate their reactivities. Products after acetylation were separated on thin-layer chromatograpy (TLC). The rates of reaction were calculated from the amounts of the products measured TLC. The observed rate constants (k1) were 6.2×10-1 (min-1) at 100°C and 9.7×l0-3 (min-1) at 0°C. Reactivity on acetylation of hydroxyl groups in G-JK decrease in the order of 6-OH<3-OH<14-OH<16-OH. At 0°C, only 6-acetyl G-n was selectively synsesized from G-IH. © 1991, The Chemical Society of Japan. All rights reserved.