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Passibiflorin, (1S,4R)-1-(β- d -glucopyranosyloxy)-4-(6-deoxy-β- d -gulopyranosyloxy)-2-cyclopentene-1-carbonitrile, was isolated from Passiflora colinvauxii endemic to the Galapagos Islands; the plant is only the second known source of passibiflorin. The glycoside was identified by spectroscopic methods. Some preparations of the plant material contained the corresponding amide, the structure of which was inferred from spectroscopic data and confirmed by chemical correlation with passibiflorin. Chemotaxonomic implications of the occurrence of bisglycosidic cyclopentanoids in Passiflora are briefly discussed.

A new cyanogenic glycoside isolated from pods of Acacia sieberiana var. woodii has been shown by chemical and spectroscopic methods to be (2S)-2-[(6-O-α- l -arabinopyranosyl-β- d -glucopyranosyl)oxy]-3-methylbut-3-enenitrileo. Acid-catalysed hydrolysis of the glycoside afforded arabinose and proacacipetalin, and base-catalysed double-bond migration gave 2- [(6-O-α- l -arabinopyranosyl-β- d -glucopyranosyl)oxy ]-3-methylbut-2-enenitrile.

The structure of plantamajoside, a phenylpropanoid glycoside isolated from Plantago major subs major , is deduced from chemical, spectral and other physical evidence, to be 3,4-dihydroxy-β-phenethyl- O -β- d -glucopyranosyl-(1 →3)-4- O -caffeoyl-β- d -glucopyranoside. The Minimum Inhibitory Concentration value has been evaluated for seven plant pathogenic bacteria and for E. coli (ML 30) and S. aureus (502 A) after preliminary investigations by the agar diffusion method.

A new diol glucoside, 2-β- d -glucopyranosyloxy-2-methylpropanol, the first reported naturally occurring monoglucoside of an aliphatic dihydric alcohol, was isolated from pods of Acacia sieberana var. woodii . Structure elucidation was based on 1 H and 13 C NMR spectroscopy, and enzymatic analyses. The compound was hydrolysed very slowly by almond β-glucosidase, but cleaved by a β-glucuronidase enzyme complex from Helix pomatia .

A new cyanogenic glucoside, isolated from pods of Acacia sieberiana var. woodii, was shown to be (2R)-2- (β- d -glucopyranosyloxy)-3-hydroxy-3-methylbutanenitrile by spectroscopic and chemical methods. The absolute configuration of this glucoside was correlated with that of proacacipetalin by oxymercuration of the latter, followed by borohydride reduction of the product.