Vasorelaxant 4,5-seco-abietane diterpenoids with diverse 6/6/6, 6/6/7, and 6/6/8 architectures from Salvia prattii Hemsl.

Abstract

Salpratins A–D (1–4), four new 4,5-seco-abietane diterpenoids, along with twelve known analogues, featuring diverse 6/6/6, 6/6/7, and 6/6/8 rings system, were isolated from Salvia prattii Hemsl. Particularly, salpratin A is the first example of 4,5;12,13-bis-seco-abietane diterpenoid features with a 5/6/6/6 ring system. Their structures were determined by analyses of comprehensive NMR and MS spectroscopic data and single-crystal X-ray diffractions. In addition, compounds 1, 3, 4, 6, 7, 8 and 14 showed potent vasorelaxant activity on endothelium-intact thoracic aorta rings precontracted with KCl.