6,7-disubstituted 2,4-diaminopteridines: novel inhibitors of Pneumocystis carinii and Toxoplasma gondii dihydrofolate reductase.
6,7-disubstituted 2,4-diaminopteridines: novel inhibitors of Pneumocystis carinii and Toxoplasma gondii dihydrofolate reductase.
复制标题
6,7-二取代的2,4-二氨基蝶啶：卡氏肺孢子虫和弓形虫二氢叶酸还原酶的新型抑制剂。
DOI：
10.1128/aac.40.6.1371
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发表时间：
1996
影响因子：
4.9
通讯作者：
Smith,JE
中科院分区：
文献类型：
--
作者：
Jackson,HC;Biggadike,K;McKilligin,E;Kinsman,OS;Queener,SF;Lane,A;Smith,JE
Four novel, disubstituted diaminopteridines have been identified which antagonize the uptake of a folate precursor (para-aminobenzoic acid) by rat-derived Pneumocystis carinii maintained in short-term axenic culture at concentrations ranging from 4.5 to 26 microM. The compounds were at least 10 to 100 times more active than trimethoprim in this assay. None of these entities exhibited toxicity to mammalian cell lines at < 100 microM. The same structures also caused significant inhibition of Toxoplasma gondii tachyzoite replication within Madin-Darby bovine kidney cells at concentrations ranging from 0.1 to 10 microM. Three of the structures (GR92754, AH10639, and AH2504) were at least an order of magnitude more potent than the standard anti-T. gondii agent, pyrimethamine. All three entities were also significantly more potent and selective than pyrimethamine as inhibitors of T. gondii dihydrofolate reductase (DHFR), with 50% inhibitory concentrations within the range of 0.018 to 0.033 microM. One of these compounds, 6,7-dibutyl-2,4-diaminopteridine (GR92754), was also a potent and selective inhibitor of P. carinii DHFR (50% inhibitory concentration, 0.082 microM). GR92754 is the first DHFR inhibitor described that exhibits greater potency, selectivity, and intracellular activity against both organisms than any of the DHFR agents used clinically, namely, trimethoprim, pyrimethamine, and trimetrexate. This information could provide the starting point for examination of the pharmacokinetic and therapeutic potential of GR92754 and related chemical entities with animal models.
