Two new 23S,26R-hydroxylated spirostanoid saponins from the fruits of Solanum indicum var. recurvatum.

ABSTRACT

Solanum indicum var. recurvatum, distributed mainly in Hekou, Simao and Menghai areas of Yunnan province, China, is characterized by stellate pubescent leaves with irregular lengths and oblong, short, and downwardly curved anthers. The original species, S. indicum, has been used as an anti-inflammatory, wound-healing agent, an analgesic, and for the treatment of rhinitis, cough, and breast cancer in Chinese folk medicine. The variety was chemically studied for the first time, leading to the isolation of two new rare 23S,26R-hydroxylated spirostanoid saponins, together with five known steroidal components, two of which the rare natural ketosteroids 6-hydroxyandrosta-1,4-diene-3,17-dione and rostadienedione have been isolated from the genus Solanum for the first time. Elucidation of the structures was accomplished by extensive 1D and 2D NMR, UV, and HRESIMS spectroscopic methods.