Identification and quantification of the fatty acids and isolation of (+)-pinitol, liriodenine, and (−)- N -acetyl-anonaine from empty capsules of Michelia champaca fruits. Crystal structure of (−)- N -acetylanonaine

The identity of fatty acids, as their methyl esters, present in the empty seed pods of Michelia champaca is reported as well as the characterisation of three compounds, namely (+)-pinitol, liriodenine, and (−)- N -acetylanonaine. The identification of these compounds was generally obtained by spectroscopic methods, and additionally by X-ray crystallography for N -acetylanonaine. The antimicrobial activity of the isolated compounds against the Gram-positive test strains Bacillus cereus ATCC 11778, Listeria monocitogenes ATCC 15313, and Staphylococcus aureus ATCC 29213 is described. In general (−)- N -acetylanonaine was the most active compound. However, the selectivity of liriodenine towards S. aureus suggests that further study would be worthwhile. (−)- N -Acetylanonaine crystallizes in the orthorhombic space group P 2 1 2 1 2 1 with a = 6.0773(2) Å, b = 11.6053(5) Å, c = 20.9906(9) (11) Å, and Z = 4. Graphical abstract