Cyanogenic glycosides and menisdaurin from Guazuma ulmifolia, Ostrya virginiana, Tiquilia plicata, and Tiquilia canescens

Leaf material of Guazuma ulmifolia (Sterculiaceae) contains mainly the cyanogenic glycoside (2R) taxiphyllin, whereas that of Ostrya virginiana (Betulaceae) contains primarily (2S)-dhurrin (1a). This cpd co-occurs in Tiquilia canescens and Tiquilia plicata (Boraginaceae) with the nitrile glucoside menisdaurin. The compounds were identified by NMR spectroscopy and the structure of 1a was determined by X-ray crystallography.