Találati lista | Tudóstér

001-es BibID:	BIBFORM001193
Első szerző:	Kéki Sándor (polimer kémikus)
Cím:	Energy-variable collision-induced dissociation study of 1,3,5-trisubstituted 2-pyrazolines by electrospray mass spectrometry / Sándor Kéki, Lajos Nagy, János Török, Katalin Tóth, Albert Lévai, Miklós Zsuga
Dátum:	2007
Megjegyzések:	The pathways of the ([M+H]+) ions generated from electrosprayed solutions of nine 1,3,5-trisubstituted 2-pyrazoline derivatives were studied using energy-variable collision-induced dissociation (CID) and pseudo-MS3 (in-source CID combined with MS/MS) methods. It was shown that under CID conditions several structurally important product ions such as the 2,4-substituted azete and 1,2-substituted aziridine ions were formed. The compositions of the product ions were unambiguously supported by accurate mass measurement (mass accuracy was within +/-8 ppm). The fragmentation pathways of 1,3,5-trisubstituted 2-pyrazolines were established by means of pseudo-MS3. It was found that a substituent at the N-1 position greatly affects the fragmentation pathways of the 2-pyrazoline derivatives. The 1-acetyl- and 1-propionyl-2-pyrazoline derivatives dissociate mainly through formation of a pyrazolium cation, while in the case of 1-phenyl-2-pyrazoline derivatives product ions arising from the consecutive fragmentation of 2,4-substituted azete and 1,2-substituted aziridine ions dominate. Another interesting finding is the formation of a radical cation from the 2,4-substituted azete by loss of a methyl radical. The fragmentation yield as a function of the collision energy for each of the 1,3,5-trisubstituted 2-pyrazolines was determined. Based on the fragmentation yield versus collision energy curves the relative fragmentation stabilities for the 1,3,5-trisubstituted 2-pyrazoline derivatives were also evaluated.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Rapid Communications in Mass Spectrometry. - 21 : 11 (2007), p. 1799-1808. -
További szerzők:	Nagy Lajos (1979-) (vegyész) Török János Tóth Katalin Zsuga Miklós (1944-) (polimer kémikus) Lévai Albert (1941-) (kémikus)
Internet cím:	DOI elektronikus változat
Borító:
Saját polcon: