much binding affinity as the CO-glutamate which it had replaced. (v) The series of compounds were poorly water soluble, and also the potent TS inhibition shown by several of them did not translate into good cytotoxicity. Compounds with large cyclic groups linked to position 4 by an SO or SO(2) group did, however, have IC(50)'s in the range 1-5 microM. Of these, 4-(N-((3,4-dihydro-2-methyl-6-quinazolin
为了开发新型的亲脂性
胸苷酸合酶(
TS)
抑制剂,大肠杆菌
TS与Fd
UMP的三元复合物的X射线结构和
抑制剂10-炔丙基-5,8-二氮杂
草酸(CB3717)被用作基于结构的基础设计。总共合成了31种缺乏谷
氨酸残基的新型亲脂性
TS抑制剂。它们中的26个共有N-(((3,4-二氢-2-甲基-6-
喹唑啉基)甲基)-N-丙-2-炔基
苯胺+ ++结构,其中
苯胺被简单的亲脂性取代基适当取代在位置3或4,或同时在两个位置。测试化合物对大肠杆菌
TS和人
TS的抑制作用,以及对鼠白血病,人白血病和胸腺
嘧啶激酶缺陷型人腺癌的组织培养生长的抑制作用。确定了五种与大肠杆菌
TS复合的
抑制剂的晶体结构。这项研究得出了五个主要结论。(i)3个取代基,例如CF(3),
碘或
乙炔基,最多可将结合提高1个数量级,在CF(3)的情况下,已证明可填充酶附近的一个口袋。(ii)一个简单的强吸电子取代基,如4位的NO(2)或CF(3)SO(2