Biaryl amino acid templates in place of d-Pro-l-Pro in cyclic ß-hairpin cationic antimicrobial peptidomimetics
作者:Nityakalyani Srinivas、Kerstin Moehle、Khaled Abou-Hadeed、Daniel Obrecht、John A. Robinson
DOI:10.1039/b706370a
日期:——
The turn-forming D-Pro-L-Pro template has been frequently used to promote regular ß-hairpin conformations in cyclic protein epitope mimetics. Here the use of three isomeric biaryl templates has been studied as alternatives to D-Pro-L-Pro in the preparation of ß-hairpin peptidomimetics. The o,o′- o,m′- and m,m′-isomers of carboxymethyl- and aminomethyl-substituted biaryl templates have been incorporated into novel macrocyclic mimics of the naturally occurring cationic antimicrobial peptide protegrin I. The presence of the o-carboxymethyl-o′-aminomethyl-biaryl template within the macrocyclic peptide resulted in the appearance of slowly interconverting atropisomers. Although none of the resulting mimetics adopted stable ß-hairpin structures in aqueous solution, they all nevertheless retained a significant antimicrobial activity against Gram positive and Gram negative bacteria. These mimetics provide interesting starting points for an optimization program in the search for potent and novel antimicrobial compounds.
转向形成的D-Pro-L-Pro模板常被用于促进环状蛋白表位模拟物中的规则β-发夹构象。这里研究了三种异构体的双芳基模板作为D-Pro-L-Pro的替代品,用于制备β-发夹肽模拟物。o,o'、o,m'和m,m'异构体的羧甲基和氨甲基取代的双芳基模板被引入到自然发生的阳离子抗菌肽protegrin I的新型宏环模拟物中。o-羧甲基-o'-氨甲基双芳基模板的存在使得宏环肽中出现了缓慢互变的厄尔托普异构体。尽管最终得到的模拟物在水溶液中未能形成稳定的β-发夹结构,它们仍保留了对革兰氏阳性和革兰氏阴性细菌的显著抗菌活性。这些模拟物为寻找强效和新型抗菌化合物的优化程序提供了有趣的出发点。