reactions was investigated. As a model for segment couplings, Ac-Phe-OH was coupled to HCl·H-Ala-OMe using the mixed anhydride, DCC1, DCCl/HOBt, BOP-Castro and TBTU-Knorr methods. As a model for stepwise synthesis Z-Phe-OH was coupled with HCl·Ala-O(t-Bu), using symmetrical anhydrides and active esters. The effects of salt additives such as LiCl, LiBr, LiC104, and ZnCl2 on yields, side-product formation, racemisation
研究了
锂盐对肽偶联反应过程的影响。作为链段偶联的模型,使用混合酸酐,
DCC1,
DCCl /
HOBt,BOP- Castro和TBTU- Knorr方法将Ac-Phe-OH与HCl·H-Ala-OMe偶联。作为逐步合成的模型,使用对称酸酐和活性酯将Z-Phe-OH与HCl·Ala-O(t -Bu)偶联。报道了诸如LiCl,LiBr,LiC10 4和ZnCl 2的盐添加剂对产率,副产物形成,外消旋化和反应速率的影响。