Isolation and structure elucidation of halymeniaol, a new antimalarial sterol derivative from the red alga Halymenia floresii

Abstract

A new mono-hydroxy acetylated sterol derivative: 12β-hydroxy-3β, 15α, 16β-triacetoxy-cholest-5-en-7-one (halymeniaol) (1), and cholesterol (2) were isolated from the marine red alga Halymenia floresii. The structure of the compound 1 (halymeniaol) was established from its spectral data, derived from HRMS/MS and 2D NMR. Compound 1 exhibited growth inhibitory activity against chloroquine-resistant Plasmodium falciparum 3D7 strain with an IC₅₀ of 3.0 μM.

Keywords:

• Algae
• sterols
• NMR & mass spectrometry
• natural products
• antimalarial activity

Acknowledgments

We are thankful to NMR Research Centre and Mass facility at IISER Pune, to Chinmay Lowalekar and Deepali Jadhav for NMR services and Uttara Lele and Neha Shintre for field collection of algae. I am grateful to Sneha and Avantika for their help in the manuscript preparation.