PURINE ANALOG ANTIMYCOBACTERIAL DRUG DEVELOPMENT

通过niaid资助的结核病抗菌药物获取和协调设施（TAACF），我们已经确定了许多抗结核分枝杆菌（M. tb）先导化合物，它们在结构上与嘌呤碱基和核苷相似。这项拨款提案的目标是了解这些药物在结核分枝杆菌和人类细胞中的代谢，以确定其选择性活性的基础。这些研究将导致对关键结核分枝杆菌嘌呤回收酶的底物特性的透彻理解。由于开发抗肿瘤核苷类似物的巨大努力，人们对嘌呤代谢中涉及的人类酶的底物需求了解甚多。然而，对结核分枝杆菌嘌呤代谢酶的底物特征知之甚少。所提出的研究应弥补这一不足，所获得的信息将有助于合理设计和开发基于人类和结核分枝杆菌嘌呤代谢差异的新药。在我们的初步数据中，我们已经确定了结核分枝杆菌和人类嘌呤代谢之间的代谢差异，这可能涉及结核分枝杆菌中某些腺苷类似物的选择性激活。然而，需要进一步的工作来完全表征这些药物和其他药物的作用机制。为实现这些目标，提出的具体目标是：(1)完整结核分枝杆菌中腺苷类似物的代谢和作用机制的表征；(2)结核分枝杆菌和人源嘌呤回收酶的分离与鉴定；(3)设计合成对结核分枝杆菌有选择性的腺苷类似物；(4)设计和合成2 -和6-取代纯的组合文库；(5)目的4合成化合物的初步生化评价；(6)抗m。结核活性和毒性。

Through the NIAID-sponsored Tuberculosis Antimicrobial Acquisition and Coordinating Facility (TAACF), we have identified numerous anti-Mycobacterium tuberculosis (M. tb) lead compounds that are structurally similar to purine bases and nucleosides. The goal of this grant proposal is to understand the metabolism of these agents in M. tb and human cells in order to identify the basis for their selective activity. These studies should lead to a thorough understanding of the substrate characteristics of key M. tb purine salvage enzymes. Much is known about the substrate requirements of human enzymes involved in purine metabolism, because of the considerable effort to develop antitumor nucleoside analogs. However, very little is known about the substrate characteristics of purine metabolizing enzymes in M. tb. The proposed studies should remedy this deficiency, and the information gained will be useful in the rational design and development of new agents based on metabolic differences in purine metabolism between humans and M. tb. In our preliminary data we have identified a metabolic difference between M. tb and human purine metabolism that could be involved in the selective activation in M. tb of certain adenosine analogs. However, further work is necessary to completely characterize the mechanism of action of these and other agents. The proposed specific aims to accomplish these goals are: (1) characterization of the metabolism and mechanism of action of adenosine analogs in intact M. tb; (2) isolation and characterization of purine salvage enzymes from M. tb and human sources; (3) design and synthesis of adenosine analogs selective for M. tb; (4) design and synthesis of a combinatorial library of 2 and 6-substituted purities; (5) preliminary biochemical evaluation of compounds synthesized in aim 4; and (6) evaluation of compounds for anti-M. tb activity and toxicity.