Rosmarinic acid derivatives from Salvia officinalis

Sagerinic acid, a novel cyclobutane and salvianolic acid K, derived from ro smarinic acid, were isolated together with the parent compound from polar s olvent extracts of Salvia officinalis. Their chemical structures were eluci dated by NMR and, for sagerinic acid, the stereochemistry of the substituen ts on the cyclobutane moiety was established as 3 beta,4 alpha-diaryl-1 alp ha,2 beta-dicarboxylic acid diester (mu-truxinate form). (C) 1999 Elsevier Science Ltd. All rights reserved.