Kinetics of degradation and oil solubility of ester prodrugs of a model dipeptide (Gly-Phe)
作者:Susan Weng Larsen、Michael Ankersen、Claus Larsen
DOI:10.1016/j.ejps.2004.04.013
日期:2004.8
5-diketopiperazine and (2) hydrolysis of the ester bond producing the dipeptide. The cyclisation reaction was dominating in the decomposition of methyl (II) butyl (III) octyl (IV) decyl (V) and dodecyl (VI) esters of Gly-Phe at pH 7.4. However, this degradation pathway was almost negligible for pH below 6. During degradation of the dipeptide esters in 80% human plasma pH 7.4 (37 degrees C) a minimal
油基长效制剂可能构成小肽的未来交付方法。因此,要求对于此类活性化合物具有足够的油溶性。通过在C端羧酸基团进行酯化反应,模型二肽(Gly-Phe)已转化为亲脂性前药。在pH 7.4(37摄氏度)下研究了Gly-Phe(IV)辛基酯的分解动力学,并且显示IV通过两个平行途径通过一级动力学降解(1)分子内氨解导致形成2 ,5-二酮哌嗪和(2)酯键的水解产生二肽。环化反应在pH 7.4的Gly-Phe的甲基(II)丁基(III)辛基(IV)癸基(V)和十二烷基(VI)酯的分解中起主要作用。但是,对于pH低于6的情况,这种降解途径几乎可以忽略不计。在80%的人类血浆pH 7.4(37摄氏度)下降解二肽酯的过程中,形成了最少量的环(-Gly-Phe)。与在水溶液pH 7.4中相比,在80%人血浆pH 7.4中酯的降解更快,这是由于肽键的快速裂解所致。观察到对Gly-Phe以及二肽酯III和VI的盐酸盐