APPROACHES TO MACROLIDE & IONOPHORE ANTIBIOTIC SYNTHESIS

一条不对称全合成十六元环的新路线 大环内酯类抗生素苷元泰勒宁和卡巴宁B正在 开发 铁羰基部分与环庚二烯基的连接 阳离子配体允许立体控制连续引入两个 取代基，最终得到5，7-二取代的环庚二烯， 可进一步加工成大环内酯类的C（1）- C（11）段。 手性识别现象的详细研究和进展 在环庚二烯基铁配合物与光学纯的 亚砜亚胺酯烯醇化物亲核试剂将允许接近这些亚基 作为自然对极。 完成大环内酯的合成 将研究通过连接C（12）- C（16）单元的糖苷配基。 的 所描述的方法具有相当大的潜在灵活性，并允许计划 大环内酯环周围的取代变化，从而使 可用于研究结构/活性的可用化合物 大环内酯系列中的关系。 2-烷氧基取代的环庚二烯基铁配合物的化学将 详细研究，导致亚基的灵活制备， 光学活性形式的离子载体抗生素离子霉素的合成。 详细研究了二烯及其铁的环官能化 复合物将进行，因为将研究到不对称的 环庚二烯和5，7-二甲基环庚二烯的官能化。 这些研究将最终导致生物碱的不对称合成 Luciduline和Prelog-Djerassi内酯。 详细研究的化学和潜在的合成效用， 将进行环辛二烯基铁络合物。

A new route for the asymmetric total synthesis of 16-membered ring macrolide antibiotic aglycones tylonolide and carbonolide B is being developed. Attachment of an iron carbonyl moiety to a cycloheptadienyl cation ligand allows stereocontrolled successive introduction of two substituents to give, ultimately, 5,7-disubstituted cycloheptadienes which can be further elaborated to C(1) - C(11) sections of the macrolides. Detailed study and development of the phenomenon of chiral recognition during reactions of cycloheptadienyliron complexes with optically pure sulfoximinyl ester enolate nucleophiles will allow access to these subunits as the natural antipodes. Completion of the synthesis of the macrolide aglycones by attachment of C(12) - C(16) units will be studied. The approach described has considerable potential fexibility and allows planned variations in substitution around the macrolide ring, thereby making available compounds which can be used to study structure/activity relationships in the macrolide series. The chemistry of 2-alkoxy-substituted cycloheptadienyliron complexes will be studied in detail, leading to a flexible preparation of subunits for synthesis of the ionophore antibiotic ionomycin, in optically active form. Detailed studies into cyclofunctionalization of dienes and their iron complexes will be undertaken, as will studies into the asymmetric functionalization of cycloheptadiene and 5,7-dimethyl cycloheptadiene. These studies will culminate in asymmetric syntheses of the alkaloid luciduline and the Prelog-Djerassi lactone. Detailed studies into the chemistry and potential synthetic utility of cyclooctadienyliron complexes will be undertaken.