Total Synthesis of (±)-Cochlearol A

Da-Wei Zhang; Wen-Dan Xu; Hui-Lan Fan; Hao-Miao Liu; Dong Chen; Dan-Dan Liu; Hong-Bo Qin

doi:10.1021/acs.orglett.9b02391

Total Synthesis of (±)-Cochlearol A

Org Lett. 2019 Sep 6;21(17):6761-6764. doi: 10.1021/acs.orglett.9b02391. Epub 2019 Aug 21.

Authors

Da-Wei Zhang^{1

2}, Wen-Dan Xu^{1

2}, Hui-Lan Fan^{1

2}, Hao-Miao Liu^{1

2}, Dong Chen^{1

2}, Dan-Dan Liu³, Hong-Bo Qin¹

Affiliations

¹ State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Yunnan Key Laboratory of Natural Medicinal Chemistry, Kunming 650201, P. R. China.
² University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
³ School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming 650500, P. R. China.

PMID: 31433660
DOI: 10.1021/acs.orglett.9b02391

Abstract

Total synthesis of (±)-cochlearol A was accomplished, which features a cis 6/6 B/D ring synthesis. A TMSOTf-promoted lactonization of tert-butoxy ketoester produced the desired lactone with quaternary carbon. The cis configuration of the B/E ring is essential for regioselective B/D ring formation. Finally, simple deprotections and transformations gave cochlearol A in 16 steps from known ethyl 4-tert-butoxyacetoacetate.

Publication types

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