Cardenolide glycosides from the aerial parts of Pergularia tomentosa.L and their biological activities

Abstract

The chemical constituents from the aerial parts of P. tomentosa.L. were studied. The constituents were isolated and purified by various chromatography methods, and the spectroscopic methods (MS, NMR) were used to identify their structures. A new cardenolide glycoside 1, along with five known cardenolide glycosides calactin (2), 12 β-hydroxycalotropin (3), 6’-hydroxycalactin (4), galakinoside (5) and uscharidin (6) were identified and isolated for the first time from Pergularia tomentosa. L. In addition, antioxidant activities of the cardenolides were studied, the highest scavenging activity of DPPH was observed in (1) (IC50 = 2050 µg/ ml), and (2) (IC50 = 2050 µg/ ml) followed by (3) (IC50 = 2178 µg/ ml), and (4) (IC50 = 3384µg/ ml). Compounds (1–6) showed no activity against the bacterial strains S. aureus bacteria (MRSA), S. aureus, and E.coli.