Studies on the β-Turn of Peptides. VII. Syntheses and Antibiotic Activities of Gramicidin S Analogs with L-Pro-L-Asn or L-Pro-D-Ala Sequence at the β-Turn Part
作者:Kazuki Sato、Ukon Nagai
DOI:10.1246/bcsj.56.3329
日期:1983.11
Two analogs of gramicidin S (GS), [L-Pro4,4′, L-Asn5,5′]-GS (10a) and [L-Pro4,4′, D-Ala5,5′]-GS were synthesized to investigate the possibility of replacing the β-turn part of GS by a different type of β-turn keeping the biological activity. For the synthesis of 10a, three procedures were examined and satisfactory results were obtained by the active ester method applied to cyclization of linear decapeptide
合成短杆菌肽 S (GS) 的两种类似物 [L-Pro4,4', L-Asn5,5']-GS (10a) 和 [L-Pro4,4', D-Ala5,5']-GS研究用不同类型的 β-转角替代 GS 的 β-转角部分的可能性,以保持生物活性。对于10a的合成,采用活性酯法在C端用L-Pro环化线性十肽,考察了三种方法,得到了满意的结果。两种类似物均未显示抗生素活性,表明 GS 的 β-转角部分不能被 L-Pro-L-Asn 或 L-Pro-D-Ala 序列取代而不影响其活性。类似物及其 2,4-二硝基苯基衍生物的 CD 和 ORD 光谱分别显示出比 GS 及其衍生物更弱的棉花效应。因此,类似物被认为不具有 GS 样 β-折叠构象。