The activity of porcine liver esterase towards diesters of 5-fluoro-2'-deoxyuridine with saturated aliphatic acids including acetic, propionic, butyric, hexanoic, octanoic, decanoic and dodecanoic acids was investigated. The susceptibility of the 3', 5'-diesters increased as the acyl chain was lengthened up to octanoyl, but further increase in the acyl chain length resulted in a sharp decrease in the susceptibility. The susceptibility of 3'-and 5'-monoesters increased as the chain was lengthened to decanoyl and slightly decreased on going to dodecanoyl. These results suggest that the higher antitumor activity of longer alkyl chain diesters of 5-fluoro-2'-deoxyuridine is partly due to their slow rates of hydrolysis by non-specific esterase.
研究了猪肝脏
酯酶对 5-
氟-
2'-脱氧尿苷与饱和脂肪族酸(包括
乙酸、
丙酸、
丁酸、
己酸、
辛酸、
癸酸和
十二酸)的二酯的活性。随着酰基链延长至辛酰,3', 5'-二酯的易感性增加,但酰基链长度的进一步增加导致易感性急剧下降。3'-和 5'-单酯的敏感性随着酰基链延长到癸酰基而增加,当延长到十二酰基时则略有下降。这些结果表明,5-
氟-
2'-脱氧尿苷的长烷基链二酯具有较高的抗肿瘤活性,部分原因是它们被非特异性
酯酶水解的速度较慢。