1,1-Diphenyl-2-methylsulfinyl ethanol: a model compound to study the reactivity towards CNBr of a photoadduct of methionine on CγH2
摘要:
The photoadduct formed by photolysis of the [Bapa(0), (pBzl)Phe(5), Met(O-2)(11)]SP/NK-1 complex localised within the (TMP175)-M-173 domain of the NK-1 receptor cannot be cleaved by CNBr on the C-side of methionine; an unusual rearrangement of the intermediate sulfonium instead Occurred. The reactivity of 1,1-diphenyl-2-methylsulfinyl ethanol 10 towards CNBr treatment and the stability of the 1,1-diphenyl oxirane 14 were analysed by NMR and mass spectrometry. 1,1-Diphenyl ethylene 13 can be formed from epoxide 14 even in slightly acidic conditions and during positive DCI/NH3 mass spectrometry analysis. Altogether, these results suggest that if a covalent linkage between the [Bapa(0), (pBzl)Phe(5), Met(O-2)(11)] and the NK-1 receptor occurred on the CyH2 of methionine-174, CNBr treatment will lead to an epoxide/ketone and an ethylenic compound. (C) 2002 Published by Elsevier Science Ltd.