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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.

Photochemical acetylthiolation of (-)-sabinene 1 afforded 10-acetylthiothujane 2 and an unexpected cyclopentenyl methyl thioacetate 3 in moderate yield (24%). Hydride reduction of these two latter compounds gave two monoterpenoid thiols ( 2a and 3a ) in excellent yield (95%). The odour of the major sulfur-containing compounds 2 and 2a was respectively described as being typically anisic and as reminiscent of cooked leek. Structural determination of these derivatives was achieved by one- and two-dimensional NMR spectroscopy.

Photochemical thioacetylation of (s−)- i -cadinene 1 afforded 5-acetylthio-cadinene 1a which was further reduced into 5-mercapto-cadinene 1b in good yield (80%). Thioepoxydation of trans -1,10-cadinene oxide 1c , prepared from m -CPBA oxidation of 1 , was also investigated. Structural determination of these derivatives was achieved by one- and two dimensional NMR spectroscopy.

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.

Laser irradiation of R(–) carvone in solution in acrylonitrile within the absorption band of its n−π* transition (≃350 nm) leads to the formation of cyclobutanic adducts, together with traces of camphocarvone.The carvone transformation is complete and appears with high quantum efficiency. The quantum yield for intermolecular reaction is intensity dependent (13–30%). This is ascribed to the fact that the reaction takes place via both a one and a two-photon absorption channel, the second being even more efficient.

The acidic fraction of benzenic extract of Blackberry bud (Ribes nigrumL.) show a diterpene acid identified as hardwickiic acid by IR., UV., RMN. and SM.