Highly stereoselective total synthesis of tylonolide, the aglycon of the 16-membered macrolide antibiotic tylosin. II. Total synthesis of tylonolide by virtue of 4-methoxybenzyl and 3,4-dimethoxybenzyl protection.
Tylonolide, was synthesized from D-glucose via coupling and cyclization of two segments i (2) (C-11-C-17) and ii (3) (C-1-C-10), which were synthesized from diacetoneglucose. A Prelog-Djerassi lactone-type compound was an intermediate in the synthesis of the latter segment. Esterification of the two segments by Yamaguchi's method followed by macrocyclization by use of the Wittig-Horner reaction gave the 16-membered cyclic enone, whose protecting groups were removed to afford tylonolide. In this total synthesis, 4-methoxybenzyl and 3, 4-dimethoxybenzyl protecting groups played an important role.
泰诺内酯(Tylonolide)是由双丙酮葡萄糖通过两个片段 i (2) (C-11-C-17)和 ii (3) (C-1-C-10)的偶联和环化合成的。一种 Prelog-Djerassi 内酯型化合物是合成后一个片段的中间体。用 Yamaguchi 方法对这两个部分进行酯化,然后用 Wittig-Horner 反应进行大环化,得到 16 元环烯酮,去除其保护基团后得到泰诺内酯。在整个合成过程中,4-甲氧基苄基和 3,4-二甲氧基苄基保护基团发挥了重要作用。
Total synthesis of tylonolide, the aglycone of the 16-membered ring macrolide tylosin, from D-glucose. Selective application of MPM and DMPM protecting groups for hydroxy functions
Segments i (C11–C17) and ii (C1–C10), synthesized from D-glucose by employing some stereoselective reactions and benzyl-type protecting groups, were esterified and cyclized to the 16-membered enone, which was readily converted to tylonolide, the aglycone of tylosin.