title: 4-Amino-3-methyl-6-phenyl-1,2,4-triazin-5(4H)-one (metamitron) and 4-amino-6-methyl-3-phenyl-1,2,4-triazin-5(4H)-one (isometamitron).
abstract: The title structures, both C(10)H(10)N(4)O, are substitutional isomers. The N-N bond lengths are longer and the C=N bond lengths are shorter by ca 0.025 A than the respective average values in the C=N-N=C group of asymmetric triazines; the assessed respective bond orders are 1.3 and 1.7. There are N-H...O and N-H...N hydrogen bonds in both structures, with 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5(4H)-one containing a rare bifurcated N-H...N,N hydrogen bond. The structures differ in their molecular stacking and the hydrogen-bonding patterns.
authors.affiliation: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, 182 23 Prague 8, Czech Republic.
authors.forename: Jirí
authors.initials: J
authors.lastname: Ludvík
authors.forename: Jirí
authors.initials: J
authors.lastname: Urban
authors.forename: Jan
authors.initials: J
authors.lastname: Fábry
authors.forename: Ivana
authors.initials: I
authors.lastname: Císarová
mesh_terms: D006860:Hydrogen Bonding; D015394:Molecular Structure; D013237:Stereoisomerism; D014227:Triazines / Q000737:chemistry*
chemical_list: D014227:Triazines; C047758:metamitron