Synthesis of 6-substituted indolactams by microbial conversion
摘要:
New indolactam derivatives (24-27) with a fluorine, bromine, iodine or methyl group at position 6 of (-)-indolactam-V (1) were synthesized from corresponding seco-compounds (6-substituted N-methyl-L-valyl-L-tryptophanols) by the microbial conversion using Streptoverticilium blastmyceticum NA34-17. (-)-5-Fluoroindolactam-V (23) and (-)-7-methylindolactam-V (28) were similarly obtained by this method. (-)-6-Methylindolactam-V (27) had almost the same biological activities as (-)-7-methylindolactam-V (28), indicating that the substituent effect at position 6 of (-)-indolactam-V (1) is similar to that at position 7.
由L-色氨酸甲酯以10个步骤制备(-)-吲哚内酰胺-V(IL-V)(1),总产率为17.1%。关键步骤包括酰基环中间体(4)的区域特异的thallation ,然后叠氮化物置换和还原以引入13-氨基。通过衍生自D-缬氨酸的手性膨胀剂(10)的S N 2置换来实现对C-11立体中心的控制。al介导的二肽的封闭(17)没有提供替代途径通往IL-V。