N-(4-Butanoyl-3-hy-droxy-phen-yl)butanamide.

The title compound, C(14)H(19)NO(3), was prepared via the intra-molecular rearrangement of 3-(butanoyl-amino)-phenyl butano-ate in the presence of anhydrous aluminium chloride. The near coplanarity of the aromatic ring, the amide group and the carbonyl group of the butanoyl fragment [N-C-C-C = -179.65 (17) and O-C-C-C = -178.34 (17)°] results from the intra-molecular O-H⋯O and C-H⋯O hydrogen bonds. In the crystal, the mol-ecules form a one-dimensional polymeric structure via N-H⋯O inter-actions between their amide groups.

N-(1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)formamide.

In the title compound, C(12)H(13)N(3)O(2), the dihedral angle between the pyrazole and benzene rings is 50.0 (3)°. In the crystal, mol-ecules are linked by inter-molecular N-H⋯O hydrogen bonds to form a three-dimensional network. Two weak C-H⋯π inter-actions reinforce the crystal packing.

4-(9,10-Dioxo-9,10-dihydro-anthracen-1-yl)-4-oxobutanoic acid.

In the title compound, C(18)H(12)O(5), the anthracene moiety is almost planar (r.m.s. deviation = 0.0399 Å). In the crystal, mol-ecules are linked to each other by inter-molecular O-H⋯O and weak C-H⋯O hydrogen bonds.