Synthesis and structural studies of flavin and alloxazine adducts with O-nucleophiles

0368922 - ÚOCHB 2012 RIV NL eng J - Článek v odborném periodiku
Ménová, P. - Eigner, V. - Čejka, J. - Dvořáková, H. - Šanda, Miloslav - Cibulka, R.
Synthesis and structural studies of flavin and alloxazine adducts with O-nucleophiles.
Journal of Molecular Structure. Roč. 1004, 1/3 (2011), s. 178-187. ISSN 0022-2860. E-ISSN 1872-8014
Grant CEP: GA ČR(CZ) GA203/07/1246
Výzkumný záměr: CEZ:AV0Z40550506
Klíčová slova: alloxazine adducts * flavin adducts * flavoenzymes * X-ray structural analysis * NMR spectroscopy * UV-VIS spectroscopy
Kód oboru RIV: CC - Organická chemie
Impakt faktor: 1.634, rok: 2011

Five flavin (isoalloxazine) and alloxazine adducts with O-nucleophiles, 5-ethyl-4a-hydroxy-3,7,8,10-tetramethyl-4a,5-dihydroisoalloxazine (1a-OH), 5-ethyl-4a-hydroxy-3,10-dimethyl-4a,5-dihydroisoalloxazine (1b-OH), 5-ethyl-4a-methoxy-3,10-dimethyl-4a,5-dihydroisoalloxazine (1b-OMe), 5-ethyl-4a-hydroxy-1,3-dimethyl-4a,5-dihydroalloxazine (2a-OH) and 5-ethyl-4a-methoxy-1,3-dimethyl-4a,5-dihydroalloxazine (2a-OMe) were prepared from the corresponding salts, 5-ethyl-3,7,8,10-tetramethylisoalloxazinium (1a), 5-ethyl-3,10-dimethylisoalloxazinium (1b) and 5-ethyl-1,3-dimethylalloxazinium (2a) perchlorates by the addition of a nucleophile (water or methanol) and triethylamine as a base. They were characterized by 1H and 13C NMR, HR-MS and UV–VIS spectra and X-ray diffraction. Flavinium and alloxazinium salts are in rapid equilibria with their adducts; the equilibrium constants for flavin adduct formation is higher by six orders of magnitude than those for alloxazine derivatives.
Trvalý link: http://hdl.handle.net/11104/0006726