Discovery through chemical synthesis of antibiotics effective against modern bacterial pathogens

项目摘要/摘要 近几十年来，细菌中出现的抗生素耐药性大大超过了新发现的抗生素 抗菌剂。本研究主要集中在抗菌素的合成和生物学研究方面。 这些现代病原体面临着紧迫的威胁。为此，林可胺已被确定为一种 未被充分利用的抗生素类。自从克林霉素被批准以来，没有新的林可胺进入市场。 50多年前(FDA，1970)。对克林霉素日益增长的抗药性及其诱发生命的倾向- 危险的艰难梭状芽胞杆菌(艰难梭菌)结肠炎限制了它在今天的医疗机构中的应用。由于 这类天然产物结构复杂，半合成策略不足以支撑未来 在这个或相关支架内发现抗生素药物。在这里，将开发高效的合成途径，并 实施来准备大量的林可胺类似物，任何其他方法都无法获得。这些 包括领先候选药物伊波沙星类似物，其特征是新型双环氧对丙氨酰胺支架 在体外和体内对广泛的多药耐药(MDR)细菌都是有效的。后者 包括MDR ESKAPE病原体(粪肠球菌、金黄色葡萄球菌、肺炎克雷伯菌 鲍曼不动杆菌、铜绿假单胞菌和肠杆菌属)，被世界卫生组织确定为目标 在抗生素开发中具有最优先的地位。通过阐明在体内的机制基础和驱动因素 伊波沙星和未来的先导抗生素的有效性，这项研究将提供多种新型抗生素支架用于 针对这些具有挑战性的病原体进行临床前探索。

PROJECT SUMMARY/ABSTRACT In recent decades, the emergence of antibiotic resistance in bacteria has greatly outpaced the discovery of novel antibacterial agents. This research is focused on the synthesis and biological study of antibiotics effective against these modern pathogens of urgent threat. To this end, the lincosamides have been identified as an underexploited class of antibiotics. No new lincosamide has entered the market since clindamycin was approved more than 50 years ago (FDA, 1970). Growing resistance to clindamycin and its propensity to induce life- threatening Clostridioides difficile (C. difficile) colitis have limited its utility in today’s armamentarium. Due to the structural complexity of this class of natural products, semi-synthetic strategies are insufficient to support future antibiotic drug discovery within this or related scaffolds. Here, efficient synthetic pathways will be developed and implemented to prepare a large collection of lincosamide analogs inaccessible by any other means. These include analogs of a lead candidate, iboxamycin, which features a novel bicyclic oxepanoprolinamide scaffold and is efficacious in vitro and in vivo against a broad range of multi-drug resistant (MDR) bacteria. The latter include MDR ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.), identified by the WHO as targets of highest priority in antibiotic development. By elucidating the mechanistic underpinnings and drivers of in vivo efficacy of iboxamycin and future lead antibiotics, this research will deliver multiple novel antibiotic scaffolds for preclinical exploration to target these challenging pathogens.