Crystal structure of 8-(4-methylphenyl)-3-(propan-2-yl)-7,8-dihydroimidazo[2,1-c][1,2,4]triazin-4(6h)-one: a potential antitumor agent

For the first time, the single crystal X-ray diffraction data are reported for the potential pharmaceutical of the formula C15H18N4O, i.e., 8-(4-methylphenyl)-3-(propan-2-yl)-7,8-dihydroimidazo[2,1c][1,2,4]triazin-4(6H)-one (1). Its structural framework is defined as the 1,2,4-triazin-4-one system fused at N5 and C9 atoms with the imidazolidine ring. The compound in question crystallizes in the triclinic space group P-1 with three molecules (Z??? = 3) in the asymmetric unit (ASU) with a = 12.440(1) ??, b = 13.577(1) ??, c = 14.682(1) ??, a = 68.70(1)??, ?? = 77.63(1)??, g = 66.55(1)??, V = 2112.5(3) ??3, Z = 6. The overall geometry of the 7,8-dihydroimidazo[2,1-c][1,2,4]triazin-4(6H)-one template is comparable in all three conformers (1-A, 1-B, 1-C) present in ASU. However, a difference in geometry between the two fused heterocyclic ring systems is observed. The six-membered 1,2,4-triazine ring is flat in all conformers. In turn, the five-membered imidazolidine ring is found to be slightly distorted from planarity in the molecules 1-A and 1-C, while it is capable of adopting an envelope conformation with the C7 methylene group as a flap in 1-B. The 4-methylphenyl substituent in the conformer 1-B is found to be visibly distorted from the plane of the imidazolidine system while in 1-A and 1-C it is almost co-planar with the central imidazolidine ring. There is a lack of strong hydrogen bonds in the studied crystal. The formation of weak C???H??????O/N/?? hydrogen bonds is stimulated by the attendance of numerous hydrogen bond acceptors and highly polarized C???H groups. The geometry of intermolecular and intramolecular interactions observed in the crystal of the title compound as well as the intermolecular interaction patterns and supramolecular synthons are discussed.