Dianthus erinaceus var. erinaceus: Extraction, isolation, characterization and antimicrobial activity investigation of novel saponins

A phytochemical analysis of Dianthus erinaceus Boiss. var. erinaceus (Caryophyllaceae) has led to the isolation of two novel triterpenoid saponins, containing an oleane type skeleton, named dianosides K and L (1, 2), along with six known triterpenoid saponins (3-8). On the basis of chemical and spectrometric data, the structures of the new compounds were elucidated as 3-O-[beta-D-glucopyranosyl (1 -> 3)]-[beta-D-glucopyranosyl (1 -> 6)]-beta-D-glucopyranosyl-olean-12-ene-23 alpha,28-beta-dioic acid 28-O-beta-D-glucopyranosyl ester (1) and 3-O-[beta-D-glucopyranosyl (1 -> 3)]-[beta-D-glucopyranosyl(1 -> 6)]-beta-D-glucopyranosyl-olean-12-ene-23 alpha,28-beta-dioic acid 28-O-alpha-L-mannopyranosyl (1 -> 6)-beta-D-glucopyranosyl ester (2). All isolated natural compounds were structurally characterized by 1D-(H-1, C-13, DEPT); 2D-(COSY, HMQC, HMBC) NMR and HR-ESI/MS methods. The antimicrobial activity of compounds 1 and 2 were tested against four Gram-negative, three Gram-positive bacteria and the yeast Candida albicans by the MIC method. (C) 2016 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.