Enantioselective Total Synthesis of (+)-Steenkrotin A and Determination of Its Absolute Configuration

Saiyong Pan; Beiling Gao; Jialei Hu; Jun Xuan; Hujun Xie; Hanfeng Ding

doi:10.1002/chem.201503831

Enantioselective Total Synthesis of (+)-Steenkrotin A and Determination of Its Absolute Configuration

Chemistry. 2016 Jan 18;22(3):959-70. doi: 10.1002/chem.201503831. Epub 2015 Dec 11.

Authors

Saiyong Pan¹, Beiling Gao¹, Jialei Hu¹, Jun Xuan¹, Hujun Xie², Hanfeng Ding³

Affiliations

¹ Department of Chemistry, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.
² College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, 310036, P.R. China.
³ Department of Chemistry, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China. hfding@zju.edu.cn.

PMID: 26660855
DOI: 10.1002/chem.201503831

Abstract

The first enantioselective total synthesis of (+)-steenkrotin A has been achieved in 18 steps and 4.2 % overall yield. The key features of the strategy entail a Rh-catalyzed O-H bond insertion followed by an intramolecular carbonyl-ene reaction, two sequential SmI2 -mediated Ueno-Stork and ketyl-olefin cyclizations, and a cascade intramolecular aldol condensation/vinylogous retro-aldol/aldol process with inversion of the relative configuration at the C7 position. The absolute configuration of (+)-steenkrotin A was determined based on the stepwise construction of the stereocenters during the total synthesis.

Keywords: carbenoids; fused-ring systems; natural products; radical reactions; total synthesis.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Biological Products / chemical synthesis*
Biological Products / chemistry*
Catalysis
Cyclization
Diterpenes / chemical synthesis*
Diterpenes / chemistry*
Stereoisomerism

Substances

Biological Products
Diterpenes
steenkrotin A