Depsitinuside: a new depside galactoside from an endophytic fungus isolated from Viburnum tinus

Abstract

Chromatographic purification of the extract of an endophytic fungal culture yielded depsitinuside (1), a new phenolic ester together with ergosterol (2) and (22E,24S)-24-methyl-5-α-cholesta-7,22-diene-3β,5,6β-triol (3). The structure of 1 was elucidated based on 1D, 2D NMR spectroscopy and high-resolution mass spectrometry, whereas the known compounds (2 and 3) were identified by ¹H NMR, mass spectrometry, and in comparison with the literature values. Compound 1 was evaluated for its enzyme inhibitory potential against acetylcholinesterase, butyrylcholinesterase and lipoxygenase, and was found inactive (10%–40% inhibition at a concentration of 2 mg/ml).

Keywords:

• Viburnum tinus
• endophytic fungus
• depside
• steroids
• enzyme inhibition

Acknowledgements

Muhammad Saleem is thankful to the Alaxander von Humboldt (AvH) Foundation, Germany, for financial support. He is also obliged to Third World Academy of Science (TWAS), Italy, for providing some of the basic laboratory facilities in Chemistry Department of IUB. We thank Kathrin Meier for excellent technical assistance.