A conjugate addition/dipolar-cycloaddition cascade sequence for the synthesis of (±)-cylindricine C

被引：20

作者：

Flick, Andrew C. ^{[1
]}

Arevalo Caballero, Maria Jose ^{[1
]}

Padwa, Albert ^{[1
]}

机构：

[1] Emory Univ, Dept Chem, Atlanta, GA 30322 USA

来源：

TETRAHEDRON | 2010年 / 66卷 / 21期

基金：

美国国家科学基金会;

关键词：

Alkaloid; Cylindricine C; 2,3-Bis(phenylsulfonyl)-1,3-butadiene; Oxime; Nitrone; Intramolecular dipolar cycloaddition; ASCIDIAN CLAVELINA-CYLINDRICA; MARINE ALKALOID LEPADIFORMINE; MERCURIC ACETATE OXIDATION; DIPOLAR CYCLOADDITION; UNSATURATED AMINES; ASYMMETRIC-SYNTHESIS; NATURAL ENANTIOMER; TERMINAL OLEFINS; (+)-CYLINDRICINE-C; (-)-LEPADIFORMINE;

D O I：

10.1016/j.tet.2010.03.088

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

An efficient stereocontrolled route to (+/-)-cylindricine C is described. Reaction of 9-hydroxynon-1-en-5-one oxime with 2,3-bis(phenylsulfonyl)-1,3-butadiene affords a 7-oxa-1-azanorbornane cycloadduct in high yield. The formation of the bicyclic isoxazolidine arises from conjugate addition of the oxime onto the diene to give a transient nitrone that spontaneously undergoes an intramolecular dipolar cycloaddition. The resulting cycloadduct derived from the cascade sequence was converted into (+/-)-cylindricine C by: (1) a reductive-cyclization to set the BC-ring skeleton, (2) a base-induced cyclization to construct the tricyclic core, and (3) an oxidation-conjugate addition of the n-hexyl side chain to complete the synthesis. (C) 2010 Elsevier Ltd. All rights reserved.

引用

页码：3643 / 3650

页数：8

共 59 条

[1] Total synthesis of the tricyclic marine alkaloids (-)-lepadiformine, (+)-cylindricine C, and (-)-fasicularin via a common intermediate formed by formic acid-induced intramolecular conjugate azaspirocyclization [J].