No abstract

In the title pyrazole compound, C21H15N3O4, an intra­molecular C—H⋯O hydrogen bond generates an S(7) ring motif. The essentially planar furan and pyrazole rings [maximum atomic deviations of 0.011 (2) and 0.006 (2) Å, respectively] make a dihedral angle of 9.21 (11)°. The nitro group is approximately coplanar with the attached furan ring, as indicated by the dihedral angle of 4.5 (2)°. In the crystal structure, inter­molecular C—H⋯O inter­actions form bifurcated hydrogen bonds, generating R 1 2(7) ring motifs. These hydrogen bonds link the mol­ecules into infinite chains along the a axis. The crystal structure is further stabilized by weak inter­molecular π–π inter­actions [centroid–centroid distance = 3.4118 (10) Å].

The asymmetric unit of the title polymeric complex, {[Sn2=(C6H5)6(C3H2O4)(H2O)]·C3H6O}n, comprises of two Sn cations, one malonate anion and a non-coordinating acetone solvent mol­ecule. Both crystallographically independent Sn cations are five-coordinated by two O and three C atoms in a distorted trigonal-bipyrimidal geometry. One of the Sn cations is bridged by the malonate units, affording polymeric chains which run along [001]. Weak intra­molecular C—H⋯π inter­actions stabilize the mol­ecular structure. In the crystal structure, adjacent chains are inter­connected by inter­molecular O—H⋯O and C—H⋯O hydrogen bonds into a three-dimensional supra­molecular structure. A weak inter­molecular C—H⋯π inter­action is also observed.

In the title salt (systematic name: 6-amino-9H-purin-1-ium perchlorate), C5H6N5 +·ClO4 −, the adeninium cation is essentially planar, with a maximum deviation of 0.038 (1) Å. The whole of the perchlorate anion is disordered over two sets of sites with an occupancy ratio of 0.589 (13):0.411 (13). In the crystal, the adeninium cations are linked by pairs of N—H⋯N hydrogen bond into inversion dimers. The dimers and the anions are further inter­connected into a three-dimensional supra­molecular structure via inter­molecular N—H⋯O, C—H⋯O and C—H⋯N hydrogen bonds.

The title hydrazide compound, C20H24N2O2, exists in a trans configuration with respect to the acyclic C=N bond and an intra­molecular O—H⋯N hydrogen bond generates an S(6) ring motif. The mean plane through the formohydrazide unit is essentially planar [maximum deviation = 0.025 (2) Å], and forms dihedral angles of 24.45 (16) and 87.14 (16)° with the two benzene rings. In the crystal structure, inter­molecular N—H⋯O and C—H⋯O hydrogen bonds link neighbouring mol­ecules into extended chains along the c axis, which incorporate R 2 2(16) ring motifs. An inter­molecular C—H⋯π inter­action is also observed.