Paratrimerins A and B, two new dimeric monoterpene-linked coumarin glycosides from the roots and stems of paramignya trimera

Abstract

Two new dimeric monoterpene-linked coumarin glucosides, paratrimerins A (1) and B (2), and three known coumarins, 6-(6-hydroxy-3,7-dimethylocta-2,7-dienyl)-7-hydroxycoumarin (3), ostruthin (4), and ninhvanin (5), were isolated from the roots and stems of Paramignya trimera (Oliv.) Guill. collected in Khanh Hoa province, Vietnam. Compound 1 comprises two 7-O-β-D-glucopyranoside coumarins linked at positions 6,6' via a 1,3,4,4-tetrasubstituted cyclohexene containing a monoterpene bridge, whereas compound 2 is a β-D-apiofuranosyl(1→6)-β-D-glucopyranosyl derivative of 1. The chemical structures of these compounds were determined by one dimensional (1D) and 2D-NMR and high resolution-electrospray ionization (HR-ESI)-MS spectroscopy.