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The synthesis of 2-mercapto-p-menth-8-ene (3) and 1-mercapto-p-menth-8-ene (4) are described, starting, respectively, from thioepoxydation of (+)-trans-limonene 1,2-epoxide (1a) and (+)-cis-limonene 1,2-epoxide (1b) via hydride reduction of episulphides 2a and 2b. Structural determination of these sulphur-containing terpenoids was achieved by one- and two-dimensional NMR spectroscopy. The odours of these two new monoterpene thiols were described, respectively, as reminescent of grapefruit juice and as being typically alliaceous. Copyright © 2002 John Wiley & Sons, Ltd.

The selective oxidation reactions of thiazolidines were studied. The synthesis of 2- and 3-thiazolines, as well as that of thiazoles, thiazolidine-1-oxides and thiazolidine-1,1-dioxides, are presented. Olfactory analysis of several of these compounds reveals interesting notes with thresholds in the ppm range, in most cases related to foodstuffs. Copyright © 2002 John Wiley & Sons, Ltd.

3-Propyl-γ-sultine has been identified for the first time in extracts of yellow passion fruit (Passiflora edulis f. flavicarpa). The chemical structure of this new molecule was confirmed by synthesis. Some other analogues were prepared using a general and efficient method. A biosynthetic pathway involving the presence of 3-sulphanylhexanol as a precursor is proposed. In addition, the chirality of the natural sultine has been evaluated by chiral gas chromatography. Copyright © 2002 John Wiley & Sons, Ltd.

Volatile compounds from guava (Psidium guajava L.) were extracted using dichloromethane. Among these volatile compounds, methyl 2-methyl-thiazolidine-4-(R)-carboxylate (cis and trans) and the ethyl 2-methyl-thiazolidine-4-(R)-carboxylate (cis and trans) could be identified for the first time in fruits. The chemical synthesis of the reference compounds and other analogues allowed the further comparison with the guava extracted thiazolidines. The absolute configuration of the cis/trans isomers was determined by nuclear magnetic resonance (1H-NMR) and by nuclear overhauser enhancement (2D NMR NOESY). Copyright © 2001 John Wiley & Sons, Ltd.