[A new triterpenoid from Cardiospermum halicacabum]

Seventeen compounds were isolated from the 80% ethanol extracts of Cardiospermum halicacabum using various chromatographic techniques, including silica gel, MCI, Sephadex LH-20 and semi-preparative high-performance liquid chromatography. The structures of the compounds were elucidated by spectroscopic analysis, such as ultraviolet-visible spectroscopy(UV), infrared spectroscopy(IR), high-resolution electrospray ionization mass spectrometry(HR-ESI-MS) and one-dimensional/two-dimensional nuclear magnetic resonance(1D/2D NMR). The compounds were identified as: cardiospermone(1), 3β,6β-dihydroxy-21αH-24-norhopa-4(23),22(29)-diene(2), 3β-hydroxyolean-12-en-11-one(3), 18α-olean-12-ene-3,11-dione(4), β-amyrin(5), campest-4-en-3-one(6),(24S)6β-hydroxycampest-4-en-3-one(7), campestane-3,6-dione(8), stigmastane-3,6-dione(9), stigmasta-22-en-3,6-dione(10), stigmasta-4,22-dien-3-one(11),(20R)-6β-hydroxystigmasta-4,22-dien-3-one(12), β-sitostenone(13), 6β-hydroxystigmast-4-en-3-one(14), 7β-hydroxystigmast-4-en-3-one(15), 7-oxo-β-sitosterol(16), 3β-hydroxy-stigmasta-5,22-dien-7-one(17). Among them, compound 1 was identified as a new triterpenoid, while all compounds were isolated from this species for the first time. The inhibitory activities of compound 1 against α-glucosidase were assessed using the 4-nitrophenyl-α-D-glucopyranoside(PNPG) method. The results indicated that compound 1 exhibited moderate inhibitory activity on α-glucosidase at a concentration of 50 μmol·L~(-1), with an inhibition rate of 73.52%.