Exploration of Some Heterocyclic Compounds Containing Trifluoromethylpyridine Scaffold as Insecticides Toward Aphis gossypii Insects.

Five types of heterocyclic compounds containing trifloromethylpyridine scaffold namely; 3-cyano-2-(N-phenyl)carbamoylmethylthio-6-(thiophen-2-yl)-4-trifluoromethyl-pyridine (6a), thieno[2,3-b]pyridines 3-5 and 7a-c, pyrido[3',2':4,5]thieno[3,2-d] pyrimidines 8-13 and 15a-c, pyrido[3',2':4,5]thieno[3,2-d][1,2,3]triazines 16a,b, and 9-(thiophen-2-yl)-7-(trifluoromethyl) pyrido [3',2':4,5]thieno[2,3-e][1,2,4]triazolo[1,5-c]pyrimidine (14) were synthesized in excellent yields and very pure state. The structures of these compounds were confirmed by elemental and spectral analyses. Most of the synthesized compounds were evaluated as insecticidal agents toward Aphis gossypii insects and promising results obtained. Among all tested compounds, only 6, 7a, 7c and 15c being the most potent compounds against nymphs and adults of Aphis gossypii and their activities are nearly to that of acetamiprid as a reference. The effect of 6a compounds 7a, 7c and 15c on the Aphis digestive system from histological point of view was also included.

Crystal structure and Hirshfeld surface analysis of 2-{[7-acetyl-4-cyano-6-hy-droxy-8-(4-meth-oxyphen-yl)-1,6-dimethyl-5,6,7,8-tetra-hydro-isoquinolin-3-yl-]sulfan-yl}acetic acid ethyl ester.

In the title mol-ecule, C25H28N2O5S, (alternative name ethyl 2-{[7-acetyl-4-cyano-6-hy-droxy-8-(4-meth-oxy-phen-yl)-1,6-dimethyl-5,6,7,8-tetra-hydro-isoquinolin-3-yl]sulfanyl}-acetate) the 4-meth-oxy-phenyl group is disposed on one side of the bicyclic core and the oxygen atoms of the hydroxyl and acetyl groups are disposed on the other side. In the crystal, a layered structure parallel to the ac plane is generated by O-H⋯O and C-H⋯O hydrogen bonds plus C-H⋯π(ring) inter-actions.

Crystal structures of two hydrazide derivatives of mefenamic acid, 3-(2,3-di-methyl-anilino)-N'-[(E)-(furan-2-yl)methyl-idene]benzohydrazide and N'-[(E)-benzyl-idene]-2-(2,3-di-methyl-anilino)benzo-hydrazide.

The conformation about the central benzene ring in the mol-ecule of (I), C20H19N3O2, is partially determined by an intra-molecular N-H⋯O hydrogen bond. In the crystal, chains parallel to the c axis are generated by inter-molecular N-H⋯O hydrogen bonds with the chains assembled into a three-dimensional network structure by inter-molecular C-H⋯O hydrogen bonds and C-H⋯π(ring) inter-actions. The mol-ecule of (II), C22H21N3O, differs from (I) only in the substituent at the hydrazide N atom where a phenyl-methyl-ene moiety for (II) is present instead of a furan-methyl-ene moiety for (I). Hence, mol-ecules of (I) and (II) show similarities in their mol-ecular and crystal structures. The conformation of the central portion of the mol-ecule of (II) is also therefore partially determined by an intra-molecular N-H⋯O hydrogen bond and inter-molecular N-H⋯O hydrogen bonds form chains parallel to the c axis. Likewise, the chains are connected into a three-dimensional network by C-H⋯O hydrogen bonds and C-H⋯π(ring) inter-actions.

Crystal structure and Hirshfeld surface analysis of 3-[(1E)-(4-{4-[(E)-(3-hy-droxy-benzyl-idene)amino]-phen-oxy}phenyl-imino)-meth-yl]phenol.

In the crystal, the mol-ecule of the title compound, C26H20N2O3, has crystallographically imposed twofold rotation symmetry. The crystal packing consists of layers parallel to the ab plane formed by O-H⋯N and C-H⋯O hydrogen bonds. Between the layers, C-H⋯π inter-actions are observed.

Crystallographic and spectroscopic characterization of 2-[(7-acetyl-4-cyano-6-hy-droxy-1,6-dimethyl-8-phenyl-5,6,7,8-tetra-hydro-isoquinolin-3-yl)sulfan-yl]-N-phenyl-acetamide.

In the title mol-ecule, C28H27N3O3S, the heterocyclic portion of the tetra-hydro-iso-quinoline unit is planar and an intra-molecular N-H⋯N hydrogen bond and a C-H⋯π(ring) inter-action help to determine the overall conformation. In the crystal, a layer structure with the layers parallel to (10) is generated by O-H⋯O and C-H⋯O hydrogen bonds.