ANTIMALARIAL ACTIVITY OF OROTIC ACID ANALOGS

近几十年来，恶性疟原虫重新成为主要的健康来源。 世界上大多数热带地区的威胁。我们最近做了 体外实验表明，5-氟代甲酸对P. 恶性(IC_(30)=6×10~(-9)M)。相比之下，5-氟甲酸酯的毒性要小得多。 对人纤维肉瘤细胞(IC30=5×10~(-5)M)。此外，两种技术的结合 尿苷和5-氟代甲酸表示，哺乳动物细胞在没有 降低5-氟代苦参碱的抗疟疾活性。最后，5- 氟甲酸酯对多种耐药寄生虫非常有效。 这项拟议研究的主要目标是确定分子 5-氟罗特酸盐选择性抗疟疾活性的基础。我们会 5-氟代苦参碱在感染红细胞中的转运特征 与恶性疟原虫的异步群和同步群在一起。我们 也会跟随放射性药物代谢成核苷酸和 转化为大分子，如核糖核酸和胸苷合成酶。 将进行实验以确定疟疾灭活是否 胸苷合成酶在疟疾灭活中的作用 胸苷合成酶在疟疾灭活中的作用 胸苷合成酶在5-氟代核苷毒性中起作用。动能 将分析寄生虫5-氟-2‘-脱氧尿苷之间的相互作用。 将合成一种新的抗代谢药物--反式5-氟二氢巴豆酸酯，并 作为一种选择性抗疟疾药物进行测试。如果在体外成功，它将 告诉我们二氢罗丹明的衍生物也可能是非常有效的 抗疟疾药物。

In recent decades Plasmodium falciparum has re-emerged as the major health threat in most tropical regions of the world. We have recently demonstrated, in vitro, that 5-fluoroorotate is exceedingly toxic to P. falciparum (IC30=6x10-9M). In contrast, 5-fluoroorotate is much less toxic to human fibrosarcoma cells (IC30=5x10-5M). Furthermore, the combination of uridine and 5-fluoroorotate says mammalian cells from toxicity without compromising the antimalarial activity of 5-fluoroorotate. Finally, 5- fluoroorotate is very effective against multiple drug-resistant parasites. The primary goal of the proposed research is to determine the molecular basis for the selective antimalarial activity of 5-fluoroorotate. We will characterize the transport of 5-fluoroorotate into erythrocytes infected with asynchronous as well as synchronous populations of P. falciparum. We will also follow the metabolism of radioactive drug into nucleotides and into macromolecules such as RNA, and the enzyme thymidylate synthetase. Experiments will be performed to determine whether inactivation of malarial thymidylate synthetase plays a role in whether inactivation of malarial thymidylate synthetase plays a role in whether inactivation of malarial thymidylate synthetase plays a role in 5-fluoroorotate toxicity. Kinetic interactions between parasite 5-fluoro 2' -deoxyuridylate will be analyzed. A new antimetabolite, trans 5-fluorodihydrocrotate will be synthesized and tested as a selective antimalarial drug. If successful in vitro, it will tell us that derivatives of dihydroorotate may also be highly effective antimalarial drugs.