Synthesis of conformationally restricted cyclic pentadepsipeptides via direct amide cyclization
作者:Kristian N Koch、Anthony Linden、Heinz Heimgartner
DOI:10.1016/s0040-4020(01)00091-6
日期:2001.3
containing four α,α-disubstituted α-amino acids, the pentapeptides 13, were synthesized starting with β-hydroxy acids 5 via the ‘azirine/oxazolone method’. The cyclic depsipeptides 14 were formed via ‘direct amide cyclization’ and the influence of several factors on this cyclization was investigated in the following way: (a) using the same composition of α,α-disubstituted α-amino acids, but changing
2,2-二取代的2 H -azirin-3-amines 6(3-amino-2 H -azirines)被用作制备16元环状二肽14的α,α-二取代的α-氨基酸的结构单元14。经由“叠氮基/恶唑酮法”以β-羟基酸5为起点合成了包含四个α,α-二取代的α-氨基酸的线性前体五肽13。环状二肽14通过“直接酰胺环化”形成,并通过以下方式研究了几种因素对该环化的影响:(a)使用相同组成的α,α-二取代α-氨基酸,但改变了它们在肽中的各自位置链; (b)在肽链中使用不同的C端α,α-二取代的α-氨基酸;(c)使用不同的β-羟基酸;(d)使用不同的肽非对映异构体。