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In this paper we describe the unprecedented reaction between α-diazo esters 1 and iodine. The reaction, carried out in the presence of aqueous NaHCO3, afforded the Z-isomer of the corresponding unsaturated-2-iodo ester 8. The configuration of compounds 8 was determined using the 3JC&bond;H coupling between carbonyl carbon atom and alkene proton. Mechanistic considerations accounting for the observed phenomena and including quantum chemical calculations are proposed. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The reaction of formaldehyde with enantiomerically pure α-N-protected amino acid hydrazides is described. The system has been investigated in different solvents, including both aqueous formaldehyde and paraformaldehyde, with the aim of simplifying the final reaction mixture. Aqueous formaldehyde in refluxing THF proved to be the best combination, affording mainly the corresponding monomeric N-methylene and 1,3,5-trisubstituted-1,3,5-hexahydrotriazine derivatives. The monomeric form was the only one present at high temperature, as evidenced by 1H and 13C NMR spectroscopy. [ABSTRACT FROM AUTHOR]

A rapid and efficient method for the synthesis of N-carbamoyl-L-amino acids is reported. The procedure, involving the reaction between urea and α-amino acids sodium salts, was performed under microwave conditions using an unmodified domestic microwave oven. A careful study of the operative conditions indicated proline (1d) as the less reactive substrate and phenylglycine (1e) as the more reactive one among all the α-amino acids tested. Substitution of urea with potassium cyanate produced a low conversion into the corresponding N-carbamoyl derivative, and a possible explanation of this result is reported. [ABSTRACT FROM AUTHOR]

alpha-Amino acids and alpha-amino methyl esters are easily converted to their N-monoalkyl derivatives by a reductive condensation reaction using several carbonyl compounds in the presence of sodium borohydride. This reducing agent has shown a wide versatility with minor but essential procedural variations. The reaction allows the alpha-monodeuterium labeling of the new N-substituent by use of sodium borodeuteride.Key words: alpha-amino acid, alpha-amino methyl esters, sodium borohydride, reductive N-monoalkylation, carbonyl compounds.Les acides alpha-aminés et leurs esters peuvent facilement être transformés en leurs dérivés N-monoalkylés par le biais d'une réaction de condensation réductrice faisant appel à divers composés carbonylés, en présence de borohydrure de sodium. Il a été démontré que ce réactif présente une grande versatilité par rapport aux variations mineures, mais essentielles, dans les procédures. L'utilisation de borodeutérure de sodium permet d'obtenir les dérivés portant un atome de deutérium en position alpha de l'azote portant le nouveau substituant.Mots clés : acide alpha-aminé, esters méthyliques d'acide alpha-aminé, borohydrure de sodium, N-monoalkylation réductrice, composés carbonylés.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Highlights • An evaluation of multi-functionality of cultivation systems was taken into account. • A multi-criteria method was employed to assess the degree of multi-functionality. • Conventional, organic and biodynamic farming methods were taken into account. • Production of wild rocket (Diplotaxis tenuifolia) was considered. • The best multi-functional indicator was obtained in the case of the biodynamic farm. Abstract Evaluating the economic, social and environmental impacts of different cultivation systems is an essential issue for the introduction of management practices that aim at both achieving more sustainable forms of land use and improving social well-being. A number of studies compared and assessed organic and conventional farms in relation to their multifunctional effects. However, to our knowledge there is no literature which took into account at the same time the multifunctional role of a greater number of different farming methods. In this paper an attempt is made to employ the multi-criteria method in order to conduct quantitative assessment of the degree of multi-functionality on three different farming methods, namely, conventional, organic and biodynamic. A species of leaf vegetable was considered, that is, wild rocket. The three farms taken into examination are all located in the province of Udine, Italy, with a maximum distance of about 20 km one from another. In all the three farms, greenhouses equipped with the same type of roofing were employed. The research was carried on for two consecutive years, that is, 2012 and 2013; spring, summer and autumn productions were considered. In this way we minimized the influence of some parameters (climatic conditions, luminosity, growing period), but the specific techniques adopted in the three farms were not optimized. The producers continued to utilize the methods usually employed in their farms, in order to obtain results showing the productive situation of the territory. The obtained information was used as input data for the multi-attribute model. Attributes and utility functions were organized under three major groups: economic, social and environmental parameters. Findings may be regarded simply as the results of a pilot study, as they were obtained on a small sample of farms, but suggest that the degree of multi-functionality is the most explicit in the case of the biodynamic farm, that has a better property and social structure. [ABSTRACT FROM AUTHOR]

The composition of the surface waxes of three apple ( Malus domestica L.) cultivars ("Florina", "Golden B" and "Ozark Gold") has been studied by means of spectroscopic and GC–MS analysis of the class-fractionated mixture of components. Odd n -alkanes, mainly C27 and C29 molecules, are prevalent in the saturated fraction. Small concentrations of alkenes were also found; the C28:1 component is strongly (72%) in excess over the other 1-alkenes. Straight-chain esters (mainly of palmitic acid) of saturated primary alcohols (C18–C30) were also detected; whereas the acyl moiety is made up essentially of an even number of carbons, the alcohol counterpart does not exhibit this characteristic. Aldehydes are present (C20–C30) with the homologue patterns C26–C30 most strongly represented. Straight-chain free secondary alcohols characterize the waxes of "Florina" and "Ozark Gold"; the hydroxy function is located far from the extremity of the carbon framework. Outstanding is the presence of three alcohols with 29 carbon centres. These alcohols are accompanied by free straight-chain primary alcohols, mainly with even-numbered carbon chains in the range C26–C30. Free fatty acids are present; all of have a framework of even-numbered carbon chains mainly in the range C16–C20. C18:1 (oleic acid) is well represented. [ABSTRACT FROM AUTHOR]