α,α-Disubstituted Glycines Bearing a Large Hydrocarbon Ring: Peptide Self-Assembly through Hydrophobic Recognition
作者:Tomohiko Ohwada、Daisuke Kojima、Tatsuto Kiwada、Shiroh Futaki、Yukio Sugiura、Kentaro Yamaguchi、Yoshinori Nishi、Yuji Kobayashi
DOI:10.1002/chem.200305492
日期:2004.2.6
A method was developed for synthesizing alpha,alpha-disubstituted glycine residues bearing a large (more than 15-membered) hydrophobic ring. The ring-closing metathesis reactions of the dialkenylated malonate precursors proceed efficiently, particularly when long methylene chains tether both terminal olefin groups. Surprisingly, the amino groups of these alpha,alpha-disubstituted glycines are inert
开发了一种合成带有大(超过15元)疏水环的α,α-二取代甘氨酸残基的方法。二烯丙基化的丙二酸酯前体的闭环复分解反应有效地进行,特别是当长的亚甲基链束缚两个末端烯烃基团时。令人惊讶地,这些α,α-二取代的甘氨酸的氨基对常规保护反应是惰性的(例如,N-叔丁氧羰基(Boc)保护:Boc(2)O / 4-二甲基氨基吡啶(DMAP)/ CH(2)Cl (2); N-苄氧羰基(Z)保护:Z-Cl / DMAP / CH(2)Cl(2))。闭环易位后丙二酸酯衍生物的羧酸官能团的库尔修斯重排导致胺官能团的形成,并可被二苯基磷酰基叠氮化物催化。然而,即使存在诸如苄醇之类的醇,也只能分离出中间体异氰酸酯。高产率地分离在质子惰性溶剂(苯)中通过库尔修斯重排获得的异氰酸酯,并在回流下在高沸点溶剂(甲苯)中用9-芴基甲醇处理,得到保护的N-9-芴基甲氧基羰基氨基丙二酸酯衍生物,收率高。这些疏水性氨基酸可通过Fmoc