title: Covalent bonding of azoles to quaternary protoberberine alkaloids.
abstract: Adducts of the quaternary protoberberine alkaloids (QPA) berberine, palmatine, and coptisine were prepared with nucleophiles derived from pyrrole, pyrazole, imidazole, and 1,2,4-triazole. The products, 8-substituted 7,8-dihydroprotoberberines, were identified by mass spectrometry and 1D and 2D NMR spectroscopy, including (1)H--(15)N shift correlations at natural abundance. In addition, two adducts of QPA with chloroform and methanethiolate were characterized by using NMR data. Single-crystal X-ray structures of 8-pyrrolyl-7,8-dihydroberberine, 8-pyrazolyl-7,8-dihydroberberine, and 8-imidazolyl-7,8-dihydroberberine are also presented.
authors.affiliation: National Center for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5/A4, CZ-625 00 Brno, Czech Republic.
authors.forename: Lenka
authors.initials: L
authors.lastname: Grycová
authors.forename: Dagmar
authors.initials: D
authors.lastname: Hulová
authors.forename: Lukás
authors.initials: L
authors.lastname: Maier
authors.forename: Stanislav
authors.initials: S
authors.lastname: Standara
authors.forename: Marek
authors.initials: M
authors.lastname: Necas
authors.forename: Filip
authors.initials: F
authors.lastname: Lemière
authors.forename: Radovan
authors.initials: R
authors.lastname: Kares
authors.forename: Jirí
authors.initials: J
authors.lastname: Dostál
authors.forename: Radek
authors.initials: R
authors.lastname: Marek
mesh_terms: D000470:Alkaloids / Q000737:chemistry*; D001393:Azoles / Q000737:chemistry*; D001599:Berberine / Q000031:analogs & derivatives / Q000737:chemistry; D001600:Berberine Alkaloids / Q000138:chemical synthesis / Q000737:chemistry*; D002625:Chemistry, Organic / Q000379:methods; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry
chemical_list: D000470:Alkaloids; D001393:Azoles; D001600:Berberine Alkaloids; C034384:coptisine; D001599:Berberine; C009090:protoberberine; C005413:palmatine