Planta Med 2015; 81 - PM_23
DOI: 10.1055/s-0035-1565400

Structures and bioactivities of withanolides from the leaves of Solanum capsicoides

BW Chen 1, YC Lin 1, JH Sheu 1, 2
  • 1Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan
  • 2Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University, Kaohsiung, Taiwan

A known withanolide steroid cilistol G (1) [1] and six new related withanolides, capsisteroids A-F (2- 7), were isolated from the acetone extract of the leaves of Solanum capsicoides. The structures of compounds 1- 7 were elucidated by extensive spectroscopic analysis, including 2D NMR spectroscopy (COSY, HSQC, HMBC, and NOESY). The structure of 1 was further confirmed by a single-crystal X-ray diffraction analysis. It was found that 1, possessing 26 S configuration, is not stable for prolonged periods of time, and was gradually epimerized to 26 R and finally reached to a 3:1 26 S/R diastereomers. These compounds were evaluated for their cytotoxicity against the proliferation of a limited panel of cancer cell lines. Further, anti-inflammatory activity of compounds 1- 7 was studied by measuring their ability in suppressing superoxide anion generation and elastase release in fMLP/CB-induced human neutrophils.

Fig. 1: Molecular structure of 1 based on X-ray analysis.

References:

[1] Zhu XH, Takagi M, Ikeda S, Midzuki K, Nohara T. Withanolide-type steroids from Solanum cilistum. Phytochemistry 2001, 56: 741 – 745