hydrophobic substituent at the N8 position. The five-membered ring of 1 can be replaced by a pyridine or isoquinoline nucleus without untoward effects. Preliminary kinetic data suggest that the type of enzyme inhibition produced by the mesoionic derivatives is similar to that observed for theophylline. Thus, several novel mesoionic ring systems display activity as inhibitors of cyclic-AMP PDE and can serve
发现介电的
噻唑并
嘧啶(1)和介电的1,3,4-
噻二唑并
嘧啶(2)的几种简单的烷基和芳烷基衍
生物具有类似茶碱的活性,可作为环
AMP磷酸二酯酶(PDE)的
抑制剂。1的C 2 -C 3双键的还原或用N-甲基取代1或2的
硫原子几乎消除了活性。最佳活性似乎与N8位的疏
水取代基有关。1的五元环可以被
吡啶或
异喹啉核取代,而不会产生不利影响。初步的动力学数据表明,由中离子衍
生物产生的酶抑制作用类型与茶碱类似。从而,