The content of S-alk(en)ylcysteine sulfoxides, important nonvolatile flavor precursors, was determined in 15 different Allium species by means of gas chromatography. The method employed is based on derivatization of S-alk(en)ylcysteine sulfoxides with ethyl chloroformate followed by their reduction with sodium iodide. The total content of S-alk(en)ylcysteine sulfoxides varied considerably in the wide range between 0.02 and 1.3% fresh weight. Not only the total content but also relative proportions of individual derivatives varied to a great extent. A novel S-alkylcysteine derivative, S-ethylcysteine sulfoxide (ethiin), not previously reported to occur in Allium species, was found in most of the samples examined in trace amounts. None of the other S-alk(en)ylcysteine sulfoxides, for example, isopropyl, (Z)-1-propenyl, butyl, or pentyl, were detected in any of the samples analyzed, limiting possible levels of each of these components to

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M e t h o d L e a d i n g t o S u b s t i t u t e d 4 -A m i n o -1 -a r y l p y r a z o l e sAbstract: A new method for the synthesis of substituted 4-amino-1-arylpyrazoles is described, starting from b-enaminones and variously substituted benzenediazonium tetrafluoroborates. The reaction proceeds under mild conditions, is very simple to perform, and is applicable to a relatively wide range of substituents, both at the benaminone and diazonium salt starting materials.