Withanolides from Physalis hispida.

Area of Science:

• Natural Products Chemistry
• Phytochemistry
• Organic Chemistry

Background:

• Physalis hispida is a plant species known to produce bioactive secondary metabolites.
• Withanolides are a class of steroidal lactones with diverse pharmacological activities.

Purpose of the Study:

• To isolate and characterize new withanolides from the aerial parts of Physalis hispida.
• To elucidate the structural features of novel compounds and known analogues.

Main Methods:

• Extraction and isolation of compounds using chromatographic techniques.
• Structure elucidation utilizing spectroscopic methods (NMR, MS).
• X-ray crystallographic analysis for definitive structural confirmation of key compounds.

Main Results:

• Isolation of nine new withanolides (withahisolides A-I) and nine known compounds.
• Structural determination of compounds 1-9, with compounds 1 and 2 confirmed by X-ray crystallography.
• Identification of compounds 1-3 as the first withanolides featuring nonaromatic six-membered ring D.
• Discovery of withanolide 8 possessing a novel steroidal skeleton lacking the C-13-C-17 bond.

Conclusions:

• The study expands the structural diversity of withanolides.
• Highlights unique structural modifications in natural products from Physalis hispida.
• Provides foundational data for potential future investigations into the biological activities of these novel compounds.