title: Tautomerism of guanidines studied by (15)N NMR: 2-hydrazono-3-phenylquinazolin-4(3H)-ones and related compounds.
abstract: 2-Hydrazono-3-phenylquinazolin-4(3H)-ones 11a-i are shown by (15)N NMR to exist in DMSO solution predominantly as the imino tautomers B and not the amino tautomers A. 2-Hydrazino-benzimidazole derivative 12 and 2-hydrazino-4,6-dimethylpyrimidine derivative 13 were found to exist predominantly as the amino tautomers.
authors.affiliation: Chemistry Department, University of Florida, Gainesville, FL 32611-7200, USA. ion@chem.ufl.edu
authors.forename: Ion
authors.initials: I
authors.lastname: Ghiviriga
authors.forename: Bahaa El-Dien M
authors.initials: Bel-D
authors.lastname: El-Gendy
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Steel
authors.forename: Alan R
authors.initials: AR
authors.lastname: Katritzky
mesh_terms: D000700:Analgesics / Q000737:chemistry; D000893:Anti-Inflammatory Agents / Q000737:chemistry; D001562:Benzimidazoles / Q000737:chemistry; D018360:Crystallography, X-Ray; D055808:Drug Discovery; D006147:Guanine / Q000737:chemistry*; D006834:Hydrazines / Q000737:chemistry; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D011743:Pyrimidines / Q000737:chemistry; D052999:Quinazolinones / Q000737:chemistry*
chemical_list: D000700:Analgesics; D000893:Anti-Inflammatory Agents; D001562:Benzimidazoles; D006834:Hydrazines; D011743:Pyrimidines; D052999:Quinazolinones; C029424:hydrazine; D006147:Guanine; C031000:benzimidazole; C030986:pyrimidine