Deep‐Sea Discovery and Detective Work: Towards Solving the Hemicalide Structural Enigma through Computational NMR Analysis and Stereocontrolled Synthesis

Abstract

Dedicated to Professor Cesare Gennari on the occasion of his 70th birthdayThe marine natural product hemicalide displays potent anticancer activity. While detailed NMR experiments established the planar carbon skeleton, its full configurational assignment proved enigmatic. This Review summarises ongoing synthetic efforts and NMR studies on hemicalide, which have succeeded in reducing the number of possible stereoisomers from more than one million to a more manageable eight structures, setting the stage for a focused total synthesis campaign.

Marine natural products

“…435 Two reviews of the struggle to identify this compound were also published in 2022. 436,437 Five bromophenol NPs were synthesised for the rst time, 438 as was pyridinium alkaloid epi-tetrahydrohalicyclamine B. 439 The structure of echinosulfonic acid D has been synthesised, one year aer it was revised independently by three groups as reported in last year's review.…”