New ceramide from the aerial part of Tinospora oblongifolia with cytotoxic activities

Abstract

A new ceramide, 2,3-dihydroxy-N-[(2S,3S,4R)-1,3,4-trihydroxyicosan-2-yl[tetracosanamide (1) along with four known compounds: 2-(4′-hydroxyphenyl)-ethyl lignocerate (2), docosyl-3,4-dihydroxy-trans-cinnamate (3), β-sitosterol (4) and β-sitosterol glycoside (5) were isolated from Tinospora oblongifolia (Menispermaceae). Their structures were determined on the basis of spectroscopic methods, mass spectrometry analysis as well as chemical transformation and by comparing their physical and spectral data with those reported in the literature. Compound 1 exhibited strong cytotoxic activity against KB cells with IC₅₀ = 3.4 μM although less than that of camptothecin IC₅₀ = 0.3 μM (positive control).

Keywords::

• Tinospora oblongifolia
• Menispermaceae
• ceramide
• cytotoxicity

Acknowledgements

This work was supported by the National Commission for Science, Technology and Innovation (NACOSTI) and Germany Academic Research Exchange (DAAD) in-country scholarship [A/11/94673] to the corresponding author. Authors are grateful to Mr James Odhiambo of School of Public Health, Maseno University for carrying out the bioassay tests; Mr Simon Mathenge (retired taxonomist from the University of Nairobi, Kenya) for identification of the plant and Prof. Till Opatz of the Institute of Organic Chemistry, Johannes Gutenberg University of Mainz, Germany for NMR and HPLC-MS analysis.