Gangjee A, Mavandadi F, Queener S F, McGuire J J
Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania 15282, USA.
J Med Chem. 1995 Jun 9;38(12):2158-65. doi: 10.1021/jm00012a016.
Eight novel, nonclassical, antifolate 2,4-diamino-5-(anilinomethyl)pyrrolo[2,3-d]pyrimidines, 1-8, with 3',4',5'-trimethoxyphenyl, 3',4'-dimethoxyphenyl, 2',5'-dimethoxyphenyl, 4'-methoxyphenyl, 2',5'-diethoxyphenyl, 3',4'-dichlorophenyl, 1'naphthyl, and phenyl substituents were synthesized as potential inhibitors of dihydrofolate reductases (DHFRs). The classical analogue N-[4-[N-[(2,4-diaminopyrrolo[2,3-d]pyrimidin- 5-yl)methyl]amino]benzoyl]-L-glutamic acid (9) was also synthesized as an inhibitor of DHFR and an antitumor agent. The classical and nonclassical analogues were obtained via reductive condensations of the key intermediate 2,4-diamino-5-cyanopyrrolo[2,3-d]pyrimidine (12) with the appropriate substituted aniline or (p-aminobenzoyl)-L-glutamate followed by reduction of the intermediate Schiff bases with NaCNBH3. Compounds 1-9 were evaluated in vitro as inhibitors of rat liver (rl), Pneumocystis carinii (pc), and Toxoplasma gondii (tg) DHFRs. The nonclassical analogues were significantly selective against tgDHFR (vs rat liver DHFR), ranging from 7- to 92-fold. The inhibitory activity was lower in pcDHFR and rlDHFR (IC50s > 10(-5) M) than in tgDHFR (IC50s = 10(-6) M). The classical analogue had inhibitory activity similar to that of methotrexate (MTX) against the growth of human leukemia CCRF-CEM, A253, and FaDu squamous cell carcinoma (SCC) of the head and neck cell lines. Further evaluation of 9 against CCRF-CEM and its sublines having defined mechanisms of MTX resistance demonstrated that the analogue utilizes the reduced folate/MTX-transport system and primarily inhibits DHFR and poly-gamma-glutamylation plays a role in its mechanism of action. Compound 9 was found to be 3-fold more efficient than aminopterin as a substrate for human folylpolyglutamate synthetase.
合成了8种新型非经典抗叶酸2,4-二氨基-5-(苯胺甲基)吡咯并[2,3-d]嘧啶（1-8），其带有3',4',5'-三甲氧基苯基、3',4'-二甲氧基苯基、2',5'-二甲氧基苯基、4'-甲氧基苯基、2',5'-二乙氧基苯基、3',4'-二氯苯基、1-萘基和苯基取代基，作为二氢叶酸还原酶（DHFRs）的潜在抑制剂。还合成了经典类似物N-[4-[N-[(2,4-二氨基吡咯并[2,3-d]嘧啶-5-基)甲基]氨基]苯甲酰基]-L-谷氨酸（9），作为DHFR的抑制剂和抗肿瘤剂。通过关键中间体2,4-二氨基-5-氰基吡咯并[2,3-d]嘧啶（12）与适当的取代苯胺或（对氨基苯甲酰基）-L-谷氨酸进行还原缩合，然后用NaCNBH3还原中间体席夫碱，得到经典和非经典类似物。对化合物1-9进行了体外评估，以确定它们对大鼠肝脏（rl）、卡氏肺孢子虫（pc）和刚地弓形虫（tg）DHFRs的抑制作用。非经典类似物对tgDHFR具有显著的选择性（相对于大鼠肝脏DHFR），选择性范围为7至92倍。其对pcDHFR和rlDHFR的抑制活性较低（IC50>10^(-5) M），而对tgDHFR的抑制活性较高（IC50=10^(-6) M）。经典类似物对人白血病CCRF-CEM、A253以及头颈部鳞状细胞癌（SCC）FaDu细胞系的生长具有与甲氨蝶呤（MTX）相似的抑制活性。对9针对CCRF-CEM及其具有明确MTX耐药机制的亚系进行的进一步评估表明，该类似物利用还原型叶酸/MTX转运系统，主要抑制DHFR，并且多聚γ-谷氨酰化在其作用机制中发挥作用。发现化合物9作为人叶酸多聚谷氨酸合成酶的底物，其效率比氨蝶呤高3倍。
