title: Identification of photoproducts of hexahydroquinoline derivatives by GC-EI-MS and HPLC-ESI-MS.
abstract: Photoproducts of hexahydroquinoline derivatives have been analyzed with gas chromatography electro ionization-mass spectrometry (GC-EI-MS) and high performance chromatography electrospray ionization-mass spectrometry (HPLC-ESI-MS). The study was performed on four HHQ derivatives: 2,6,6-trimethyl-3-carbomethoxy-5-oxo-4-(R-phenyl)-1,4,5,6,7,8-hexahydroquinoline; R=2'-Me, 3'-Me, 2'-MeO, and 3'-MeO. The photochemical degradation of each of the HHQ derivatives led to the appearance of one product. The photoproducts were identified as the corresponding tetrahydroquinoline analogues, which were formed by dehydrogenation of dihydropyridine moiety. In GC-mass spectra, the most frequent way of fragmentation was elimination of CH3* or CH3O* radical of the ester group. In the photoproducts substituted at 2'-position of the phenyl ring, elimination of isobutene (C4H8) was observed. In the photoproducts with 3'-position substituents, elimination of COOCH3* radical was noted.
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780, Poland. jmielcar@am.poznan.pl
authors.forename: Jadwiga
authors.initials: J
authors.lastname: Mielcarek
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Matłoka
authors.forename: Paweł
authors.initials: P
authors.lastname: Grobelny
mesh_terms: D000465:Algorithms; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D007202:Indicators and Reagents; D010777:Photochemistry; D015363:Quinolones / Q000138:chemical synthesis* / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet
chemical_list: D007202:Indicators and Reagents; D015363:Quinolones