Synthesis, characterization, biological evaluation, and molecular docking studies of new 1,3,4-oxadiazole-thioether derivative as antioxidants and cytotoxic agents.

Oxadiazoles and their derivatives with thioether functionalities represent a new and exciting class of physiologically active heterocyclic compounds. Several molecules with these moieties play a vital role in pharmaceuticals because of their diverse biological activities. This paper describes a new class of 1,3,4- oxadiazole-2-thioethers with acetophenone, coumarin, and N-phenyl acetamide residues (S-alkylation), with the hope that the addition of various biologically active molecules will have a synergistic effect on anticancer activity. The structure of the synthesized title compounds was determined by the combined methods of IR, proton-NMR, carbon-13-NMR, and mass spectrometry. Furthermore, all the newly prepared molecules were assessed for their antioxidant activity. Furthermore, four compounds were assessed for their molecular docking interactions and cytotoxicity activity. The synthesized derivatives have shown moderate antioxidant activity compared to the standard BHA (butylated hydroxy anisole). The IC50 of the titled molecules (11b, 11c, 13b, and 14b) observed for in vitro anti-cancer activities were 11.20, 15.73, 59.61, and 27.66 g/ml at 72-h treatment time against the A549 cell lines, respectively. The tested compounds' biological evaluation showed that 11b is the most effective molecule in the series. In conclusion, the findings of this study suggest that the tested compounds, 1,3,4-oxadiazole-2-thioether derivative, have shown high cytotoxicity against human lung cancer diseases, which may serve for subsequent studies in the formulation of cancer-based drugs and future outlook for researchers.

3-Methyl-5-(4-methyl-phen-oxy)-1-phenyl-1H-pyrazole-4-carbaldehyde.

In the title compound, C18H16N2O2, the phenyl and pyrazole rings subtend a dihedral angle of 22.68 (8)°. The packing of the title compound features aromatic π-π stacking and weak C-H⋯π inter-actions.

5-(4-Fluoro-phen-yl)-1-[4-(4-methyl-phen-yl)thia-zol-2-yl]-3-[4-(prop-2-yn-yloxy)phen-yl]-4,5-di-hydro-1H-pyrazole.

In the title compound, C28H22FN3OS, four rings are almost coplanar, with the fluorophenyl ring substantially twisted. In the extended structure, aromatic π-π stacking inter-actions between the pyrazole ring and the tolyl ring link the mol-ecules into centrosymmetric dimers.

3-(3-Nitro-phen-yl)-1-[4-(prop-2-yn-yloxy)phen-yl]prop-2-en-1-one.

The structure of the title compound, C18H13NO4, shows that the whole mol-ecule is almost planar but with a dihedral angle between the two phenyl rings of 19.22 (5)°. The mol-ecules are linked by C-H⋯O inter-actions, forming sheets in the (21) plane.

Formation of 1-(thia-zol-2-yl)-4,5-di-hydropyrazoles from simple precursors: synthesis, spectroscopic characterization and the structures of an inter-mediate and two products.

Two new 1-(thia-zol-2-yl)-4,5-di-hydropyrazoles have been synthesized from simple precursors, and characterized both spectroscopically and structurally. In addition, two inter-mediates in the reaction pathway have been isolated and characterized, one of them structurally. The mol-ecules of the inter-mediate (E)-1-(4-meth-oxy-phen-yl)-3-[4-(prop-2-yn-yloxy)phen-yl]prop-2-en-1-one, C19H16O3 (I), are linked by a combination of C-H⋯O and C-H⋯π(arene) hydrogen bonds to form ribbons. The products (RS)-5-(4-meth-oxy-phen-yl)-1-(4-phenythiazol-2-yl)-3-[4-(prop-2-yn--yloxy)phen-yl]-4,5-di-hydro-1H-pyrazole, C28H23N3O2S (II), and (RS)-5-(4-meth-oxy-phen-yl)-1-[4-(4-methyl-phen-yl)thia-zol-2-yl]-3-[4-(prop-2-yn-yloxy)phen-yl]-4,5-di-hydro-1H-pyrazole, C29H25N3O2S (III), are closely related - differing only by presence or absence of a methyl group at the aryl-thia-zolyl substituent - and crystallize in an isomorphous setting. Both mol-ecules contain an effectively planar di-hydro-pyrazole ring, and possess an overall T-shaped structure, which is a characteristic of triaryl-substituted 4,5-di-hydro-1-(thia-zol-2-yl)pyrazole compounds. The crystal packing is characterized by inter-molecular C-H⋯S and C-H⋯π (ar-yl/alkyne) inter-actions. A combination of two C-H⋯π(arene) hydrogen bonds links the product mol-ecules into sheets.

Reduced 3,4'-bi-pyrazoles carrying thio-phene and thia-zole substituents: structures of two intermediates and two products.

Cyclo-addition reactions between 3-(5-ar-yloxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)-1-(thio-phen-2-yl)prop-2-en-1-ones and thio-semicarbazide leads to the formation of reduced 3,4'-bi-pyrazole-2-carbo-thio-amides. Further cyclo-addition of these inter-mediates with either diethyl acetyl-enedi-carboxyl-ate or 4-bromo-phenacyl bromide leads to reduced 3,4'-bi-pyrazoles carrying oxo-thia-zole or thia-zole substituents, respectively. The structures of two representative inter-mediates and two representative products established unambiguously the regiochemistry of the cyclo-addition reactions. The mol-ecules of 3'-methyl-5'-(2-methyl-phen-oxy)-1'-phenyl-5-(thio-phen-2-yl)-3,4-di-hydro-1'H,2H-3,4'-bi-pyra-zole-2-carbo-thio-amide, C25H23N5OS2 (Ia), are linked by N-H⋯N hydrogen bonds to form simple C(8) chains. The analogous compound 5'-(2,4-di-chloro-phen-oxy)-3'-methyl-1'-phenyl-5-(thio-phen-2-yl)-3,4-di-hydro-1'H,2H-3,4'-bi-pyra-zole-2-carbo-thio-amide hemihydrate crystallizes as a hemihydrate, C24H19Cl2N5OS2·0.5H2O (Ib), and the independent components are linked into a chain of spiro-fused R 4 4(20) rings by a combination of O-H⋯N and N-H⋯O hydrogen bonds. In the structure of ethyl (Z)-2-{2-[3'-methyl-1'-phenyl-5-(thio-phen-2-yl)-5'-(2-methyl-phen-oxy)-3,4-di-hydro-1'H,2H-3,4'-bi-pyrazole-2-yl]-4-oxo-4,5-di-hydro-thia-zol-5-yl-idene}acetate, C31H27N5O4S2 (II), inversion-related pairs of mol-ecules are linked by paired C-H⋯π(arene) hydrogen bonds to form cyclic centrosymmetric dimers, but there are no direction-specific inter-molecular inter-actions in 4-(4-bromo-phen-yl)-2-[5'-(2,4-di-chloro-phen-oxy)-3'-methyl-1'-phenyl-5-(thio-phen-2-yl)-3,4-di-hydro-1'H,2H-3,4'-bi-pyrazole-2-yl]-4-thia-zole, C32H22BrCl2N5OS2 (III). Comparisons are made with the structures of some related compounds.

The crystal structures of three disordered 2-substituted benzimidazole esters.

The crystal structures of three benzimidazole esters containing aryl or heterocyclic substituents at position 2 are reported, and all three exhibit disorder of mol-ecular entities. In ethyl 1-methyl-2-[4-(prop-2-yn-oxy)phen-yl]-1H-benzimidazole-5-carboxyl-ate, C20H18N2O3, (I), the prop-2-yn-1-oxyphenyl unit is disordered over two sets of atomic sites having effectively equal occupancies, 0.506 (5) and 0.494 (5). The propyl substituent in ethyl 1-propyl-2-(pyren-1-yl)-1H-benzimidazole-5-carboxyl-ate, C29H24N2O2, (II), is disordered over two sets of atomic sites having occupancies 0.601 (8) and 0.399 (8), and the ester unit in ethyl 1-methyl-2-(5-chloro-3-methyl-1-phenyl-1H-pyrazol-4-yl)-1H-benzimidazole-5-carboxyl-ate, C21H19ClN4O2 (III), is disordered over two sets of atomic sites having occupancies 0.645 (7) and 0.355 (7). In each of the C-H⋯π(arene) hydrogen bonds in (I), the donor and acceptor form parts of different disorder components, so that no continuous aggregation is possible. The mol-ecules of (II) are linked by a single C-H⋯O hydrogen bond into C(10) chains, which are linked into sheets by a π-π stacking inter-action, whereas those of (III) are just linked into C(13) chains, again by a single C-H⋯O hydrogen bond. Comparisons are made with the structures of some related compounds.

Different patterns of supra-molecular aggregation in three amides containing N-(benzo[d]thia-zol-yl) substituents.

Crystal structures are reported for three amides containing N-benzo[d]thia-zole substituents. In N-(benzo[d]thia-zol-6-yl)-3-bromo-benzamide, C14H9BrN2OS, where the two ring systems are nearly parallel to one another [dihedral angle = 5.8 (2)°], the mol-ecules are linked by N-H⋯O and C-H⋯N hydrogen bonds to form ribbons of R 3 3(19) rings, which are linked into sheets by short Br⋯Br inter-actions [3.5812 (6) Å]. N-(6-Meth-oxy-benzo[d]thia-zol-2-yl)-2-nitro-benzamide, C15H11N3O4S, crystallizes with Z' = 2 in space group Pna21: the dihedral angles between the ring systems [46.43 (15) and 66.35 (13)°] are significantly different in the independent mol-ecules and a combination of two N-H⋯N and five C-H⋯O hydrogen bonds links the mol-ecules into a three-dimensional network. The mol-ecules of 5-cyclo-propyl-N-(6-meth-oxy-ben-zo[d]thia-zol-2-yl)-isoxazole-3-carboxamide, C15H13N3O3S, exhibit two forms of disorder, in the meth-oxy group and in the cyclo-propyl-isoxazole unit; symmetry-related pairs of mol-ecules are linked into dimers by pairwise N-H⋯N hydrogen bonds. Comparisons are made with the structures of some related compounds.

Order versus disorder in two isomorphous pyrazolone-substituted diethyl propane-dioates prepared using a three-component one-pot reaction under solvent-free conditions.

Two new substituted propane-dioate esters have been synthesized using a three-component solvent-free thermal reaction between diethyl propane-dioate (diethyl malonate), 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde and an aryl azide, forming two new C-C bonds in a single step. The products diethyl (RS)-2-[(4-bromo-phen-yl)(5-methyl-3-oxo-2-phenyl-2,3-di-hydro-1H-pyrazol-4-yl)meth-yl]propane-dioate, C24H25BrN2O5 (I), and diethyl (RS)-2-[(4-chloro-phen-yl)(5-methyl-3-oxo-2-phenyl-2,3-di-hydro-1H-pyrazol-4-yl)meth-yl]propane-dioate, C24H25ClN2O5 (II), are isomorphous, with Z' = 2 in space group P21/n. The two independent mol-ecules in compound (I) are both fully ordered, while each of the independent mol-ecules in compound (II) is disordered, but in different ways. In one mol-ecule of (II), the N-phenyl ring is disordered over two sets of atomic sites having occupancies 0.635 (10) and 0.365 (10), and in the other mol-ecule the ester function is disordered over two sets of atomic sites having occupancies 0.690 (5) and 0.310 (5). In both structures, the two independent mol-ecules adopt different conformations and, in each structure, the mol-ecules are linked into complex sheets by a combination of N-H⋯O, C-H⋯O and C-H⋯π(arene) hydrogen bonds. Comparisons are made with some related structures.

Two N-{[4-(3-aryl-4-sydnonyl-idene-amino)-5-sulfan-yl-idene-1H-1,2,4-triazol-3-yl]meth-yl}benzamides as disordered ethanol monosolvates.

Two new N-{[4-(3-aryl-4-sydnonyl-idene-amino)-5-sulfanyl-idene-1H-1,2,4-triazol-3-yl]meth-yl}benzamides have been prepared by acid-promoted condensation reactions between 3-aryl-4-formyl-sydnones and N-[(4-amino-5-sulfanyl-idene-1H-1,2,4-triazol-3-yl)meth-yl]benzamide, and both have been crystallized as ethanol monosolvates. N-{[4-(3-Phenyl-4-sydnonyl-idene-amino)-5-sulfanyl-idene-1H-1,2,4-triazol-3-yl]meth-yl}benzamide ethanol monosolvate, C19H15N7O3S·C2H6O (I), and N-({4-[3-(4-methyl-phen-yl)-4-sydnonyl-idene-amino]-5-sulfanyl-idene-1H-1,2,4-triazol-3-yl}meth-yl)benzamide ethanol monosolvate, C20H17N7O3S·C2H6O (II), differ only in the presence of a methyl group for (II) instead of a hydrogen atom for (I), and in both of them the ethanol component is disordered over two sets of atomic sites having occupancies of 0.836 (6) and 0.164 (6) in (I), and 0.906 (6) and 0.094 (6) in (II). Combinations of O-H⋯O and N-H⋯O hydrogen bonds link the mol-ecules into cyclic, centrosymmetric four-mol-ecule aggregates. Comparisons are made with the structures of some related compounds.

Functionalized 3-(5-ar-yloxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)-1-(4-substituted-phen-yl)prop-2-en-1-ones: synthetic pathway, and the structures of six examples.

Five examples each of 3-(5-ar-yloxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)-1-[4-(prop-2-yn-1-yl-oxy)phen-yl]prop-2-en-1-ones and the corresponding 1-(4-azido-phen-yl)-3-(5-ar-yloxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)prop-2-en-1-ones have been synthesized in a highly efficient manner, starting from a common source precursor, and structures have been determined for three examples of each type. In each of 3-[5-(2-chloro-phen-oxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl]-1-[4-(prop-2-yn-1-yl-oxy)phen-yl]prop-2-en-1-one, C28H21ClN2O3, (Ib), the isomeric 3-[5-(2-chloro-phen-oxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl]-1-[4-(prop-2-yn-1-yl-oxy)phen-yl]prop-2-en-1-one, (Ic), and 3-[3-methyl-5-(naphthalen-2-yl-oxy)-1-phenyl-1H-pyrazol-4-yl]-1-[4-(prop-2-yn-yloxy)phen-yl]prop-2-en-1-one, C32H24N2O3, (Ie), the mol-ecules are linked into chains of rings, formed by two independent C-H⋯O hydrogen bonds in (Ib) and by a combination of C-H⋯O and C-H⋯π(arene) hydrogen bonds in each of (Ic) and (Ie). There are no direction-specific inter-molecular inter-actions in the structure of 1-(4-azido-phen-yl)-3-[3-methyl-5-(2-methyl-phen-oxy)-1-phenyl-1H-pyrazol-4-yl]prop-2-en-1-one, C26H21N5O2, (IIa). In 1-(4-azido-phen-yl)-3-[5-(2,4-di-chloro-phen-oxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl]prop-2-en-1-one, C25H17Cl2N5O2, (IId), the di-chloro-phenyl group is disordered over two sets of atomic sites having occupancies 0.55 (4) and 0.45 (4), and the mol-ecules are linked by a single C-H⋯O hydrogen bond to form cyclic, centrosymmetric R 2 2(20) dimers. Similar dimers are formed in 1-(4-azido-phen-yl)-3-[3-methyl-5-(naphthalen-2-yl-oxy)-1-phenyl-1H-pyrazol-4-yl]prop-2-en-1-one, C29H21N5O2, (IIe), but here the dimers are linked into a chain of rings by two independent C-H..π(arene) hydrogen bonds. Comparisons are made between the mol-ecular conformations within both series of compounds.

Conversion of di-aryl-chalcones into 4,5-di-hydro-pyrazole-1-carbo-thio-amides: mol-ecular and supra-molecular structures of two precursors and three products.

Chalcones of type 4-XC6H4C(O)CH=CHC6H4(OCH2CCH)-4, where X = Cl, Br or MeO, have been converted to the corresponding 4,5-di-hydro-pyrazole-1-carbo-thio-amides using a cyclo-condensation reaction with thio-semicarbazide. The chalcones 1-(4-chloro-phen-yl)-3-[4-(prop-2-yn-yloxy)phen-yl]prop-2-en-1-one, C18H13ClO2, (I), and 1-(4-bromo-phen-yl)-3-[4-(prop-2-yn-yloxy)phen-yl]prop-2-en-1-one, C18H13BrO2, (II), are isomorphous, and their mol-ecules are linked into sheets by two independent C-H⋯π(arene) inter-actions, both involving the same aryl ring with one C-H donor approaching each face. In each of the products (RS)-3-(4-chloro-phen-yl)-5-[4-(prop-2-yn-yloxy)phen-yl]-4,5-di-hydro-pyrazole-1-carbo-thio-amide, C19H16ClN3OS, (IV), (RS)-3-(4-bromo-phen-yl)-5-[4-(prop-2-yn-yloxy)phen-yl]-4,5-di-hydro-pyrazole-1-carbo-thio-amide, C19H16BrN3OS, (V), and (RS)-3-(4-meth-oxy-phen-yl)-5-[4-(prop-2-yn-yloxy)phen-yl]-4,5-di-hydro-pyrazole-1-carbo-thio-amide, C20H19N3O2S, (VI), the reduced pyrazole ring adopts an envelope conformation with the C atom bearing the 4-prop-2-yn-yloxy)phenyl substituent, which occupies the axial site, displaced from the plane of the four ring atoms. Compounds (IV) and (V) are isomorphous and their mol-ecules are linked into chains of edge-fused rings by a combination of N-H⋯S and C-H⋯S hydrogen bonds. The mol-ecules of (VI) are linked into sheets by a combination of N-H⋯S, N-H⋯N and C-H⋯π(arene) hydrogen bonds. Comparisons are made with the structures of some related compounds.

Two isostructural 3-(5-ar-yloxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)-1-(thio-phen-2-yl)prop-2-en-1-ones: disorder and supra-molecular assembly.

Two new chalcones containing both pyrazole and thio-phene substituents have been prepared and structurally characterized. 3-(3-Methyl-5-phen-oxy-1-phenyl-1H-pyrazol-4-yl)-1-(thio-phen-2-yl)prop-2-en-1-one, C23H18N2O2S (I), and 3-[3-methyl-5-(2-methyl-phen-oxy)-1-phenyl-1H-pyrazol-4-yl]-1-(thio-phen-2-yl)prop-2-en-1-one, C24H20N2O2S (II), are isomorphous as well as isostructural, and in each the thio-phene substituent is disordered over two sets of atomic sites having occupancies 0.844 (3) and 0.156 (3) in (I), and 0.883 (2) and 0.117 (2) in (II). In each structure, the mol-ecules are linked into sheets by a combination of C-H⋯N and C-H⋯O hydrogen bonds. Comparisons are made with some related compounds.

Conversion of substituted 5-aryloxypyrazolecarbaldehydes into reduced 3,4'-bipyrazoles: synthesis and characterization, and the structures of four precursors and two products, and their supramolecular assembly in zero, one and two dimensions.

The reaction of 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde with phenols under basic conditions yields the corresponding 5-aryloxy derivatives; the subsequent reaction of these carbaldehydes with substituted acetophenones yields the corresponding chalcones, which in turn undergo cyclocondensation reactions with hydrazine in the presence of acetic acid to form N-acetylated reduced bipyrazoles. Structures are reported for three 5-aryloxycarbaldehydes and the 5-piperidino analogue, and for two reduced bipyrazole products. 5-(2-Chlorophenoxy)-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde, C17H13ClN2O2, (II), which crystallizes with Z' = 2 in the space group P-1, exhibits orientational disorder of the carbaldehyde group in each of the two independent molecules. Each of 3-methyl-5-(4-nitrophenoxy)-1-phenyl-1H-pyrazole-4-carbaldehyde, C17H13N3O4, (IV), 3-methyl-5-(naphthalen-2-yloxy)-1-phenyl-1H-pyrazole-4-carbaldehyde, C21H16N2O2, (V), and 3-methyl-1-phenyl-5-(piperidin-1-yl)-1H-pyrazole-4-carbaldehyde, C16H19N3O, (VI), (3RS)-2-acetyl-5-(4-azidophenyl)-5'-(2-chlorophenoxy)-3'-methyl-1'-phenyl-3,4-dihydro-1'H,2H-[3,4'-bipyrazole] C27H22ClN7O2, (IX) and (3RS)-2-acetyl-5-(4-azidophenyl)-3'-methyl-5'-(naphthalen-2-yloxy)-1'-phenyl-3,4-dihydro-1'H,2H-[3,4'-bipyrazole] C31H25N7O2, (X), has Z' = 1, and each is fully ordered. The new compounds have all been fully characterized by analysis, namely IR spectroscopy, 1H and 13C NMR spectroscopy, and mass spectrometry. In each of (II), (V) and (IX), the molecules are linked into ribbons, generated respectively by combinations of C-H...N, C-H...π and C-Cl...π interactions in (II), C-H...O and C-H...π hydrogen bonds in (V), and C-H...N and C-H...O hydrogen bonds in (IX). The molecules of compounds (IV) and (IX) are both linked into sheets, by multiple C-H...O and C-H...π hydrogen bonds in (IV), and by two C-H...π hydrogen bonds in (IX). A single C-H...N hydrogen bond links the molecules of (X) into centrosymmetric dimers. Comparisons are made with the structures of some related compounds.

Four 1-aryl-1H-pyrazole-3,4-di-carboxyl-ate derivatives: synthesis, mol-ecular conformation and hydrogen bonding.

Four 1-aryl-1H-pyrazole-3,4-di-carboxyl-ate derivatives, one acid, two esters and a dicarbohydrazide have been synthesized starting from 3-aryl sydnones, and structurally characterized. There is an intra-molecular O-H⋯O hydrogen bond in 1-phenyl-1H-pyrazole-3,4-di-carb-oxy-lic acid, C11H8N2O4, (I), and the mol-ecules are linked into a three-dimensional framework structure by a combination of O-H⋯O, O-H⋯N, C-H⋯O and C-H⋯π(arene) hydrogen bonds. In each of the two esters dimethyl 1-phenyl-1H-pyrazole-3,4-di-carboxyl-ate, C13H12N2O4, (II), and dimethyl 1-(4-methyl-phen-yl)-1H-pyrazole-3,4-di-carboxyl-ate, C14H14N2O4, (III), C-H⋯O hydrogen bonds lead to the formation of cyclic centrosymmetric dimers: in (III), one of the meth-oxy-carbonyl groups is disordered over two sets of atomic sites having occupancies 0.71 (2) and 0.29 (2). An intra-molecular N-H⋯O hydrogen bond is present in the structure of 1-(4-meth-oxy-phen-yl)-1H-pyrazole-3,4-dicarbohydrazide, C12H14N6O3, (IV), and the mol-ecules are linked into a three-dimensional framework structure by a combination of N-H⋯O, N-H⋯N, N-H⋯π(arene) and C-H⋯O hydrogen bonds. Comparisons are made with the structures of a number of related compounds.

Synthesis, Spectroscopic Properties and Antioxidant Activity of Bis-Hydrazones and Schiff's bases Derived from Terephthalic Dihydrazide.

A series of novel Schiff base containing bis-1,2,4-triazole and bis-hydrazone derived from terephthalic dihydrazide was synthesized. All the newly synthesized compounds were characterized by (1)H, (13)C NMR, mass spectra, FTIR and elemental analysis. UV-vis spectra and fluorescent spectra of the compounds were recorded. The effect of substituent such as electron withdrawing and electron donating groups on the fluorescent spectra was studied. Also, the comparative discussion on fluorescent spectra of Schiff's base and hydrazones has been described. The antioxidant activity of the compounds revealed that compound 5c and 5f are the most potent compounds in this series.

Synthesis, characterization and molecular docking studies of some new 1,3,4-oxadiazolines bearing 6-methylpyridine moiety for antimicrobial property.

A new series of 3-acetyl-2-aryl-2H/methyl-5-[3-(6-methylpyridinyl)]-2,3-dihydro-[1,3,4]-oxadiazole derivatives were synthesized from 6-methyl nicotinate through a multistep reaction sequence. The structures of newly synthesized compounds were established on the basis of elemental analysis, IR, 1H NMR, 13C NMR and mass spectral data. Three dimensional structure of the compound 5f was further confirmed by single crystal X-ray analysis. All the synthesized compounds were screened for their antimicrobial activity and antioxidant activity. The final compounds were subjected to molecular docking studies for the inhibition of enzyme L-glutamine: D-fructose-6-phosphate amidotransferase [GlcN-6-P] (EC 2.6.1.16). The in silico molecular docking results are matching with the in vitro studies and they may be considered as good inhibitor of GlcN-6-P synthase.6-methylpyridine.

2-Amino-6-methyl-5-{5-[(naphthalen-2-yl-oxy)meth-yl]-1,3,4-oxadiazol-2-ylsulfan-yl}-4-(3-nitro-phen-yl)pyridine-3-carbonitrile.

The asymmetric unit of the title compound, C26H18N6O4S, contains two independent mol-ecules (A and B). The dihedral angles between the oxadiazole ring and naphthalene ring system are 42.59 (14) and 6.88 (14) Šin mol-ecules A and B, respectively. The dihedral angles between the pyridine and benzene rings in A and B are 65.53 (13 )and 87.67 (13) Å, respectively. In the crystal, mol-ecules A and B are linked through a pair of N-H⋯N hydrogen bonds involving one -NH2 group H atom and second pair of N-H⋯N hydrogen bonds involving the other -NH2 group H atom, forming an -ABAB- ribbon along [100] containing R 2 (2)(8) and R 2 (2)(12) ring motifs. These ribbons are further connected by weak C-H⋯N, C-H⋯O and C-H⋯π inter-actions, resulting in a three-dimensional network. The crystal studied was a non-merohedral twin with refined components 0.906 (1):0.094 (1).

5-(5'-Fluoro-2'-meth-oxy-biphenyl-3-yl)-1,3,4-oxa-diazol-2-amine.

In the title compound, C15H12FN3O2, the dihedral angles between the central benzene ring and the pendant benzene and oxa-diazole rings are 45.05 (13) and 15.60 (14)°, respectively. The C atom of the meth-oxy group is roughly coplanar with its attached ring [displacement = 0.178 (4) Å]. In the crystal, N-H⋯N hydrogen bonds link the mol-ecules into [010] chains. Weak C-H⋯π inter-actions are also observed.

(E)-N'-(4-Meth-oxy-benzyl-idene)-2-(2-methyl-4-nitro-1H-imidazol-1-yl)acetohydrazide.

In the title compound, C(14)H(15)N(5)O(4), the central -C=N-N-C(=O)-C- bridge is nearly planar [maximum deviation = 0.037 (1) Å] and forms dihedral angles of 7.37 (9) and 73.33 (5)°, respectively, with the benzene and imidazole rings. The dihedral angle between the benzene and imidazole rings is 66.08 (9)°. The meth-oxy and nitro groups are nearly coplanar with the benzene and imidazole rings, respectively, with a C-O-C-C torsion angle of 5.9 (2)° and an O-N-C-C angle of -0.2 (2)°. In the crystal, mol-ecules are linked by a pair of N-H⋯O hydrogen bonds with an R(2) (2)(8) ring motif, forming an inversion dimer. The dimers are further inter-connected by C-H⋯O hydrogen bonds into a sheet parallel to the (111) plane. A C-H⋯π inter-action is also observed between the sheets.