Talab sarra (8 resultados)

Condición: New.

Condición: Hervorragend. Zustand: Hervorragend | Sprache: Englisch | Produktart: Bücher | In a few simple steps starting from a commercially available reagents benzyl chloride and potassium thiocyanate, thiocyanate is obtained which is directly reacted with glycine amide to give benzyl thiourea. The used of concentrated HCl give the ring closed product of the latter. The alkylation of 3-benzyl-2- thioxoimidazolidin-4-one is made by the used of methyl iodide under basic condition. Subsequent treatment of the alkyl derivative 3-benzyl-2-(methylthio)-3,5dihydro-4-imidazole with diethyl phosphono cyanate gives the nitrile derivatives which upon treatment with sulphuric acid and functional group manipulations gave 1-benzyl-5-chloromethylimidazolium chloride. This compound is converted mildly under O¿Donnell conditions into the l- Histidine derivative. After deprotection L-Histidine is obtained in good yield with 99% enantiomeric excess. This synthetic scheme allows access to any isotopomer of L-histidine and many other biologically important imidazole derivatives.…

Taschenbuch. Condición: Neu. This item is printed on demand - it takes 3-4 days longer - Neuware -In a few simple steps starting from a commercially available reagents benzyl chloride and potassium thiocyanate, thiocyanate is obtained which is directly reacted with glycine amide to give benzyl thiourea. The used of concentrated HCl give the ring closed product of the latter. The alkylation of 3-benzyl-2- thioxoimidazolidin-4-one is made by the used of methyl iodide under basic condition. Subsequent treatment of the alkyl derivative 3-benzyl-2-(methylthio)-3,5dihydro-4-imidazole with diethyl phosphono cyanate gives the nitrile derivatives which upon treatment with sulphuric acid and functional group manipulations gave 1-benzyl-5-chloromethylimidazolium chloride. This compound is converted mildly under O'Donnell conditions into the l- Histidine derivative. After deprotection L-Histidine is obtained in good yield with 99% enantiomeric excess. This synthetic scheme allows access to any isotopomer of L-histidine and many other biologically important imidazole derivatives. 120 pp. Englisch.…

Taschenbuch. Condición: Neu. nach der Bestellung gedruckt Neuware - Printed after ordering - In a few simple steps starting from a commercially available reagents benzyl chloride and potassium thiocyanate, thiocyanate is obtained which is directly reacted with glycine amide to give benzyl thiourea. The used of concentrated HCl give the ring closed product of the latter. The alkylation of 3-benzyl-2- thioxoimidazolidin-4-one is made by the used of methyl iodide under basic condition. Subsequent treatment of the alkyl derivative 3-benzyl-2-(methylthio)-3,5dihydro-4-imidazole with diethyl phosphono cyanate gives the nitrile derivatives which upon treatment with sulphuric acid and functional group manipulations gave 1-benzyl-5-chloromethylimidazolium chloride. This compound is converted mildly under O'Donnell conditions into the l- Histidine derivative. After deprotection L-Histidine is obtained in good yield with 99% enantiomeric excess. This synthetic scheme allows access to any isotopomer of L-histidine and many other biologically important imidazole derivatives. …

Condición: New. Print on Demand.

Kartoniert / Broschiert. Condición: New. Dieser Artikel ist ein Print on Demand Artikel und wird nach Ihrer Bestellung fuer Sie gedruckt. Autor/Autorin: Talab SarraAssistant professor Organic chemistry,Chemistry Department, Collage of Science, Al Imam Mohammad Ibn Saud Isalmic University Riyadh Saudi ArabiaIn a few simple steps starting from a commercially available reagents benz.…

Condición: New. PRINT ON DEMAND.

Taschenbuch. Condición: Neu. This item is printed on demand - Print on Demand Titel. Neuware -In a few simple steps starting from a commercially available reagents benzyl chloride and potassium thiocyanate, thiocyanate is obtained which is directly reacted with glycine amide to give benzyl thiourea. The used of concentrated HCl give the ring closed product of the latter. The alkylation of 3-benzyl-2- thioxoimidazolidin-4-one is made by the used of methyl iodide under basic condition. Subsequent treatment of the alkyl derivative 3-benzyl-2-(methylthio)-3,5dihydro-4-imidazole with diethyl phosphono cyanate gives the nitrile derivatives which upon treatment with sulphuric acid and functional group manipulations gave 1-benzyl-5-chloromethylimidazolium chloride. This compound is converted mildly under O¿Donnell conditions into the l- Histidine derivative. After deprotection L-Histidine is obtained in good yield with 99% enantiomeric excess. This synthetic scheme allows access to any isotopomer of L-histidine and many other biologically important imidazole derivatives.VDM Verlag, Dudweiler Landstraße 99, 66123 Saarbrücken 120 pp. Englisch. …