Ethyl 2-isopropylamino-6-methyl-8-oxo-3-phenyl-3H,8H-furo[2,3-d][1,2,4]triazolo[1,5-a]pyrimidine-7-carboxylate

In the title compound, C20H21N5O4, the ring system containing the three fused rings is essentially planar (r.m.s. deviation for all 12 non-H atoms = 0.041 angstrom). The phenyl ring makes a dihedral angle of 54.41 (6)degrees with this ring system. The isopropyl group is disordered over two positions, with site-occupancy factors of 0.753 (9) and 0.247 (9). The structure is mainly stabilized by weak intermolecular N-H center dot center dot center dot O and intramolecular C-H center dot center dot center dot O hydrogen-bonding interactions and pi-pi interactions, with interplanar distances of 3.415 (1) angstrom between adjacent furan ring centroids and 3.420 (1) angstrom between the benzene and pyrimidinone rings.