title: Dynamic NMR study of dinitrophenyl derivatives of seven-membered cyclic ketals of pyridoxine.
abstract: Two pyridoxine derivatives containing a dinitrophenyl moiety were investigated by (1)H NMR spectroscopy. Conformational dynamics in solution were studied for each compound using dynamic NMR experiments. It was shown that both compounds studied are involved into two conformational exchange processes. The first process is a transformation of the seven-membered cycle conformation between the enantiomeric P-twist and M-twist forms, and the second is a rotation of the dinitrophenyl fragment of the molecules around the C-O bond. Energy barriers of both conformational transitions were determined.
authors.affiliation: Kazan (Volga Region) Federal University, 18 Kremlevskaya St, Kazan, 420008, Russia.
authors.forename: Ilfat Z
authors.initials: IZ
authors.lastname: Rakhmatullin
authors.affiliation: Kazan (Volga Region) Federal University, 18 Kremlevskaya St, Kazan, 420008, Russia.
authors.forename: Leisan F
authors.initials: LF
authors.lastname: Galiullina
authors.affiliation: Kazan (Volga Region) Federal University, 18 Kremlevskaya St, Kazan, 420008, Russia.
authors.forename: Marsel' R
authors.initials: MR
authors.lastname: Garipov
authors.affiliation: Kazan (Volga Region) Federal University, 18 Kremlevskaya St, Kazan, 420008, Russia.
authors.forename: Alexey D
authors.initials: AD
authors.lastname: Strel'nik
authors.affiliation: Kazan (Volga Region) Federal University, 18 Kremlevskaya St, Kazan, 420008, Russia.
authors.forename: Yurii G
authors.initials: YG
authors.lastname: Shtyrlin
authors.affiliation: Kazan (Volga Region) Federal University, 18 Kremlevskaya St, Kazan, 420008, Russia.
authors.forename: Vladimir V
authors.initials: VV
authors.lastname: Klochkov
mesh_terms: D003500:Cyclization; D004136:Dinitrobenzenes / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D011736:Pyridoxine / Q000737:chemistry*
chemical_list: D004136:Dinitrobenzenes; D007659:Ketones; D011736:Pyridoxine
keywords: conformational exchange; dynamic 1H NMR; energy barrier; ketal; pyridoxine