ABSTRACT
The title compound, C(19)H(17)ClN(4), was obtained from the reaction of 3-chloro-5,6-diphenyl-1,2,4-triazine with isobutyronitrile in the presence of lithium diisopropyl-amide as an unexpected product of covalent addition of isobutyronitrile carbanion to the C-5 atom of the 1,2,4-triazine ring. The 2,5-dihydro-1,2,4-triazine ring is essentially planar (r.m.s. deviation = 0.0059â Å) and the 5- and 6-phenyl substituents are inclined to its mean plane with dihedral angles of 89.97â (4) and 55.52â (5)°, respectively. Intra-molecular C-Hâ¯N inter-actions occur. In the crystal, mol-ecules related by a c-glide plane are linked into zigzag chains along [001] by N-Hâ¯N hydrogen bonds.
ABSTRACT
In the title compound, C(10)H(12)N(6), the two 5,6-dimethyl-1,2,4-triazine halves of the mol-ecule are related by a centre of symmetry. The two triazine rings are coplanar to within a maximum deviation of 0.013â (2)â Å from the mean plane of the ring atoms. In the crystal, mol-ecules form layers parallel to the (100) crystallographic plane. Adjacent layers are held together via a C-Hâ¯π inter-action involving mol-ecules related by an a-glide plane.
ABSTRACT
Synthesis of several pryrazolo[4,3-e][1,2,4]-triazines is described. The absorption spectrum of some 5-substituted derivatives was found to extend to the visible region. These compounds were found to inhibit some enzymes of purine metabolism, like xanthine oxidase or bacterial purine-nucleoside phosphorylase with Ki values in the 10(-3) -10(-5) M range.
Subject(s)
Light , Purines/chemistry , Pyrazoles/chemistry , Triazines/chemistry , Absorption , Animals , Cattle , Cultured Milk Products/enzymology , Drug Evaluation , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Escherichia coli/enzymology , Guanine Deaminase/antagonists & inhibitors , Guanine Deaminase/metabolism , Models, Biological , Muscles/enzymology , Purine-Nucleoside Phosphorylase/antagonists & inhibitors , Purine-Nucleoside Phosphorylase/metabolism , Purines/metabolism , Purines/pharmacology , Pyrazoles/pharmacology , Rabbits , Triazines/pharmacology , Xanthine Oxidase/antagonists & inhibitors , Xanthine Oxidase/metabolismABSTRACT
Synthesis of 2,3- and 3,4-cyclopentenopyridines, 5,6,7,8-tetrahydroquinolines and 5,6,7,8-tetrahydroisoquinolines from 1,2,4-triazine derivatives is reported. Introduction of an alpha-functionalized methyl substituent (e.g. arylsulphonyl, sulphonamide, sulphonic acid ester) into position 3- or 6- of triazines by vicarious nucleophilic substitution of hydrogen and subsequent alkylation with alkyl iodides bearing an acetylenic function in terminal position afforded valuable intermediates for intramolecular Diels-Alder reaction with inverse electron demand. When heated at higher temperature, these triazine derivatives gave the Diels-Alder cycloadducts, which, after spontaneous extrusion of nitrogen moiety, led to a variety of functionalized cycloalkenopyridine derivatives.