Thiolysis of oxazolines: A new, selective method for the direct conversion of peptide oxazolines into thiazolines
作者:Peter Wipf、Chris P. Miller、Srikanth Venkatraman、Paul C. Fritch
DOI:10.1016/0040-4039(95)01322-9
日期:1995.9
A direct oxazoline→thiazoline conversion can be realized by thiolysis of oxazolines with H2S in methanol/triethylamine, followed by cyclodehydration with Burgess reagent. This protocol is high-yielding, chemoselective, and essentially free of racemization for C(5)-unsubstituted and trans-4,5-disubstituted peptide oxazolines. Thioamide intermediates are obtained regioselectively, thus the thiolysis
通过在甲醇/三乙胺中用H 2 S对恶唑啉进行硫解,然后用Burgess试剂进行环化脱水,可实现恶唑啉→噻唑啉的直接转化。该协议是高产,化学选择性,基本上没有消旋的C(5)未取代和反式-4,5-二取代的肽恶唑啉。硫代酰胺中间体是通过区域选择性获得的,因此恶唑啉的硫解作用是用Lawesson试剂对肽进行thionation的替代方法。