Rhynchines A-E: Cav3.1 Calcium Channel Blockers from Uncaria rhynchophylla

Org Lett. 2021 Dec 17;23(24):9463-9467. doi: 10.1021/acs.orglett.1c03641. Epub 2021 Nov 24.

Abstract

Rhynchines A-E (1-5), five new indole alkaloids with an unprecedented skeleton, were isolated from Uncaria rhynchophylla. The new skeleton was characterized by an indole moiety and a 2-oxa-8-azatricyclo[6,5,01,5,01,8]tridecane core, forming a unique 6/5/7/5/5 ring system. Their structures were determined by nuclear magnetic resonance, high-resolution electrospray ionization mass spectrometry, infrared spectroscopy, and calculated electronic circular dichroism (ECD) and were confirmed by X-ray crystallography. Interestingly, 1 and 2 showed strong inhibitory activities against the Cav3.1 calcium channel with IC50 values of 6.86 and 10.41 μM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calcium Channel Blockers*

Substances

  • Calcium Channel Blockers