Ethyl 5-methyl-4-oxo-3-phenyl-2-propyl­amino-3,4-dihydro­thieno[2,3-d]pyrimidine-6-carboxyl­ate

The title compound, C19H21N3O3S, was synthesized via the aza-Wittig reaction of functionalized imino­phospho­rane with phenyl isocyanate under mild conditions. In the mol­ecule, the fused thienopyrimidine ring system is essentially planar, with a maximum deviation of 0.072 (2) Å, and makes a dihedral angle of 60.11 (9)° with the phenyl ring. An intra­molecular C—H⋯O hydrogen bond is present. The crystal packing is stabilized by inter­molecular N—H⋯O and C—H⋯O hydrogen bonds

(E)-4-(5-Hydr­oxy-2-methyl­benzyl­idene­amino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one

The title compound, C19H19N3O2, is a Schiff base compound derived from 4-amino­anti­pyrine and 5-hydr­oxy-2-methyl­benzaldehyde. The mol­ecule adopts a trans configuration about the central C=N bond. There is an intra­molecular O—H⋯N hydrogen bond. Futhermore, weak C—H⋯O hydrogen bonds lead to the formation of a chain developing parallel to the b axis

(E)-4-(4-Hydr­oxy-3-nitro­benzyl­idene­amino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one

In the title compound, C18H16N4O4, the dihedral angles between the central pyrazole ring and the pendant substituted and unsubstituted aromatic rings are 4.73 (12) and 44.24 (14)°, respectively. An intra­molecular O—H⋯O hydrogen bond occurs. In the crystal structure, an inter­molecular C—H⋯O inter­action may help to consolidate the packing and a short intra­molecular C—H⋯O contact also occurs