An Optimized Synthesis, Molecular Structure and Characterization of Benzylic Derivatives of 1,2,4-Triazin-3,5(2H,4H)-dione.

ABSTRACT: 4-Benzyl-1,2,4-triazin-3,5(2H,4H)-dione (3-benzyl-6-azauracil, 2), and 2,4-dibenzyl-1,2,4-triazin-3,5(2H,4H)-dione (1,3-dibenzyl-6-azauracil, 3) were synthesized by the reaction of 1,2,4-triazin-3,5(2H,4H)-dione (6-azauracil, 1) with benzyl bromide and potassium carbonate in dry acetone via the 18-crown-6-ether catalysis. In these reaction methods, we developed more convenient and efficient methodologies to afford compounds 2 and 3 in good yields. These compounds were characterized by ¹H- and 13C-NMR, MS spectrum, IR spectroscopy and elemental analysis. The structure of 2 was verified by 2D-NMR measurements, including gHSQC and gHMBC measurements. A single-crystal X-ray diffraction experiment indicated that compound 3, with the molecular formula C17H15N?O?, crystallized from a CH?OH/CH?Cl? diffusion solvent system in a monoclinic space group P2?/c with a = 13.7844(13), b = 8.5691(8), c = 13.0527(12) Å, ? = 105.961(2)°, V = 1482.3(2) ų, Z = 4, resulting in a density Dcalc of 1.314 g/cm³. The crystal structure of compound 3 is tightly stabilized by contact with five other molecules from the six short contacts formed by intermolecular C-O···H-Car, C-H···Car, and weakly ?···? stacking interactions. The dihedral angle 31.90° is formed by the mean planes of the benzene rings of the N-2 and N-4 benzyl groups.

SUBMITTER: Hwang LC 

PROVIDER: S-EPMC6150235 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature