1,4-Dioxane and ergosterol derivatives from Withania somnifera roots

Abstract

The chemical investigation on the n-hexane extract of Withania somnifera roots has yielded octacosane, oleic and stearic fatty acids, stigmasterone, stigmasterol, sitostanone, oleanolic acid along with the ergosterol and 1,4-dioxane derivatives as new compounds. The isolation of alkenyl-1,4-dioxane compound is rare, whereas the ergosterol derivative may have biogenetic significance in the lactone formation in the E ring of withanolides. The presence of a 1,4-dioxane derivative in the nonpolar extract of roots assumes importance as this type of compound has not been reported earlier from W. somnifera. The structures of new compounds were elucidated by spectroscopic methods and chemical transformations.

Keywords:

• Withania somnifera
• Solanaceae
• Ashwagandha
• 1,4-dioxane derivative
• ergosterol derivative

Acknowledgements

The assistance in the collection and identification of the plant material from Dr Vijayakumar, IICT, Hyderabad is gratefully acknowledged. We also thank CSIR, New Delhi for the research grant under NMITLI and Director CIMAP, Lucknow for the research facilities.