A hydrogen-bonded chain of rings in 5-amino-1-(4-methoxybenzoyl)-3-methylpyrazole and a three-dimensional hydrogen-bonded framework in 5-amino-3-methyl-1-(2-nitrobenzoyl)pyrazole.

The molecules of 5-amino-1-(4-methoxybenzoyl)-3-methylpyrazole, C(12)H(13)N(3)O(2), (I), and 5-amino-3-methyl-1-(2-nitrobenzoyl)pyrazole, C(11)H(10)N(4)O(3), (II), both contain intramolecular N-H...O hydrogen bonds. The molecules of (I) are linked into a chain of rings by a combination of N-H...N and N-H...pi(arene) hydrogen bonds, while those of (II) are linked into a three-dimensional framework structure by N-H...N and C-H...O hydrogen bonds.