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An enzyme-mediated preparation of enantiomerically pure 5-alken-2,4-diols and 4-hydroxy-5-alken-2-ones, obtained by reduction of their corresponding aldol derivatives is described. The synthetic versatility of the chirons is demonstrated by employing them as key intermediates in a new de novo approach to deoxy sugars.

The enzyme-mediated preparation and the odor evaluation of the single stereoisomers of the commercial odorants Muguesia and Pamplefleur are described. The synthetic approach to Muguesia stereoisomers helped to clear the assignment of the relative configuration of intermediate diols.

Gastric cancer represents a diffuse and aggressive neoplasm, whose mortality index is among the highest in the world. Predisposing factors are E-cadherin mutations, Helicobacter pylori infection, and a diet rich in salted and smoked food, with a low intake of fresh fruits and vegetables. Here, we analyzed the effect of total lipophilic extracts of two Southern Italy tomato varieties, San Marzano and Corbarino, on an in vitro model of gastric cancer, YCC-1, YCC-2 and YCC-3 cell lines, characterized by different aggressiveness. Our results showed a possible role of these two varieties of tomatoes against typical neoplastic features. The treatment with tomato extracts affected cancer cell ability to grow both in adherence and in semisolid medium, reducing also cell migration ability. No toxic effects were observed on non-tumoral cells. We found, on gastric cancer cell lines, effects on both cell cycle progression and apoptosis modulation. The extent of antineoplastic effects, however, did not seem to correlate with the carotenoid content and antioxidant activity of the two tomato varieties. Our data indicate that San Marzano and Corbarino intake might be further considered as nutritional support not only in cancer prevention, but also for cancer patient diet. [ABSTRACT FROM AUTHOR]

Abstract: The enantiomers of methyl ionones 1 and 2 were prepared by an enzyme-catalysed approach. Their odour properties were evaluated by skilful perfumers. [Copyright &y& Elsevier]

The enzyme-mediated synthesis of enantiomerically enriched 1,3-dioxane odorants analogous to Floropal® is here described. The complete olfactory evaluation of each sample is also reported. The addition of a single methyl group at C5 of the dioxane ring of Floropal® modifies the elicited odour sensation, still preserving a pleasant character. The substitution of the methyl group at C6 with just an ethyl moiety completely changes the odour profile of the molecule. Even subtler are the odour differences generated by configurational variations. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The enzyme-mediated synthesis of enantiomerically enriched 1,3-dioxane odorants analogous to Floropal® is here described. The complete olfactory evaluation of each sample is also reported. The addition of a single methyl group at C5 of the dioxane ring of Floropal® modifies the elicited odour sensation, still preserving a pleasant character. The substitution of the methyl group at C6 with just an ethyl moiety completely changes the odour profile of the molecule. Even subtler are the odour differences generated by configurational variations. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Two enantiomers of Undecavertol® were prepared by enzymatic methods and their odour properties evaluated. [Copyright &y& Elsevier]

All four stereoisomers of the fragrance Jasmal of structure 3,4,5,6-tetrahydro-3-pentyl-2H-pyran-4-yl acetate were prepared by enzymatic resolutions of the corresponding alcohols. The absolute configurations were unambiguously determined by comparison with the enantiomer (3R,4S)-1 prepared from L-tartaric acid. The four stereoisomers of the fragrance Jessemal of structure 3-butyl-5-methyl-3,4,5,6-tetrahydro-2H-pyran-4-yl acetate were obtained starting from the epoxy alcohol 10, which was obtained in an optically pure state by enzymatic resolution of the racemic mixture. The olfactory evaluations of all stereoisomers are reported. (1)H-NMR Conformational analysis of diastereoisomers (3RS,4RS,5RS)-2 and (3RS,4SR,5RS)-2 is also reported.