inhibited platelet aggregation with an IC50 of 0.08 microM, 15-fold more potent than the unsubstituted prototype 2. The potency of 12a was found to be sensitive to variation of the methoxy moiety. The ethyl (12b) and isopropyl (12d) esters were less effective as were the acid 12e and a series of amides (12f-h). Other substituents introduced at this site of the pharmacophore included P(O)(OEt)2 (25), SCH3
4,5-二苯基
恶唑衍
生物2-4先前被确定为非
前列腺素前列环素(
PGI2)模拟物。合成了一系列在
恶唑环的碳原子α处带有2-4个取代基的衍
生物,并将其作为体外
ADP诱导的人血小板聚集的
抑制剂。在不饱和系列中,以几何异构体的均等混合物形式评估的α-甲乙氧基衍
生物10a抑制了血小板凝集,IC50为0.36 microM。对各个甲酯衍
生物(E)-9a和(Z)-9a的评估表明,(E)-9a的效力比(Z)-9a高10倍。在饱和系列中,α-甲氧基甲氧基取代的化合物12a抑制血小板凝集,IC50为0.08 microM,效力比未取代的原型2高15倍。发现12a的效力对甲氧基部分的变化敏感。乙基(12b)和异丙基(12d)酯的效果不如酸12e和一系列酰胺(12f-h)。在药效团此位点引入的其他取代基包括P(O)(OEt)2(25),S (31a),S(O)
CH3(31b),SO2 (31c),异丙基(