SYNTHESES OF MACROLIDES AND RELATED NATURAL PRODUCTS

聚丙酸酯衍生的天然产物可用作 抗生素离子载体和信息素 的发展 高非对映选择性和对映选择性的方法， 这些物质的合成允许用于类似物的新技术 合成及有机反应研究进展 机制等 利用克莱森重排和钯- 介导的烷基化在本授予期间发展 在此期间，目前正在进行的努力将继续测试， 这种新方法在合成几种 生理活性物质。 两种抗生素，依莱叶林，特别是它的生理- 活性糖苷配基和原霉素IV将成为 合成研究，将测试我们的方法聚丙酸酯 合成和碳-碳键大环化。 该地区 离子载体，卡西霉素和X-14885-A的合成研究， 生物系统中重要的离子转运剂，将是 进行。 本发明的小齿藻素是海洋聚丙酸酯天然产物， 在结构上与假定的 抗微生物二萜皂苷。 综合努力， 它们的合成将有助于研究它们的作用机制。 阵 抗动脉粥样硬化剂庚替酸提供了一种 有机会研究分子内钯的机制- 介导的乙烯基环氧化物的烷基化，并证明绝对 通过合成来构造这种物质。 所有这些项目目前都在调查之中。

Polypropionate-derived natural products can function as antibiotics, ionophores and pheromones. The development of highly diastereoselective and enantioselective methods for the synthesis of these substances permits new techniques for analog synthesis and the advancement of the study of organic reaction mechanisms. Using Claisen rearrangements and palladium- mediated alkylations developed during the present granting period, efforts currently underway will be continued to test the efficacy of this new methodology in the synthesis of several physiologically-active substances. Two antibiotics, elaiophylin, in particular its physiologically- active aglycones, and protomycinolide IV, will be the subjects of synthetic studies that will test our method for polypropionate synthesis and carbon-carbon bond macrocyclization. In the area of ionophores, synthetic studies on calcimycin and X-14885-A, important ion transport agents in biological systems, will be conducted. The denticulatins are marine polypropionate natural products that are structurally related to putative biogenetic precursors of the antimicrobial diemenesins. Synthetic efforts directed toward their synthesis will aid in the study of the mechanism of their formation. The anti-cholesteremic agent, heptelidic acid, provides an opportunity to study the mechanism of intramolecular palladium- mediated alkylations of vinyl epoxides and to prove the absolute configuration of this substance by synthesis. All of these projects are currently under investigation.