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This work was inspired by a previous report (Janjua et al. J. Phys. Chem. A 113, 3576–3587, 2009) in which the nonlinear-optical (NLO) response strikingly improved with an increase in the conjugation path. Herein, the effect of donor and acceptor substitutions on the geometrical parameters, electronic, optical and reactivity of argon in organic matrices has been computed by computational methods. The 6–311 ++ g(2d,2p) basis set and second order Moller–Plesset perturbation theory are used to explore mixed-argon benzonitrile compounds (1–7) namely; hydrogen argon cyanide, methyl argon cyanide, phenyl argon cyanide, cyano-phenyl argon cyanide, hydroxy-phenyl argon cyanide, nitro-phenyl argon cyanide and methoxy-phenyl argon cyanide respectively. Mullikan population analysis, natural bonding orbital (NBO) analysis, frontier molecular orbital analysis, molecular electrostatic potential surface analysis, polarizability and hyperpolarizability of noble gases in organic matrices have been studied. The results indicate that the electron donating groups (hydroxy, methoxy, phenyl and methyl) and electron withdrawing groups (nitro and cyano) fine tune the HOMO–LUMO orbitals and nonlinear optical properties. NBO analysis confirmed that these donor–acceptor groups support the charge transfer in our investigated jack-in-the-box compounds. The linear polarizability and first hyperpolarizability results suggest that all the studied compounds are good candidates for NLO response and associated applications.

Synthesis of C-2 N-substituted anthranilamide derivatives was carried out in a straight forward manner, utilizing 2-aminobenzamide and benzyl chloride as starting materials. Their crystal structures have been established by single crystal X-ray crystallographic method. In the molecules of 2-benzylamino-benzamide (3a), intramolecular hydrogen bonding b/w O atom and proton of –NH and classical intermolecular hydrogen bonding of the type N–H · · · O forming eight membered rings in R4 2(8) pattern. In both molecules of 2-(dibenzylamino)benzamide (3b), unlike the molecule in 3a, each H atoms is pointed towards N atom causing intramolecular hydrogen bonding interactions, resulting in S(6) motifs. However, it is interesting to note that both molecules in 3b are lying about inversion centres and form dimers in R4 2(8) motifs; the two dimers are linked via non-classical intermolecular hydrogen bonds C–H · · · O resulting in clusters of four molecules in the structure. In vitro assay results revealed that molecule 3b with IC50 values of 3.8 ± 0.08 μM (AChE) and 17.6 ± 1.10 μM (BChE) possessed better cholinesterase (AChE and BChE) inhibition potential as compared to standard drug galantamine. Preliminary in silico studies showed that more biological active derivatives were also having good pharmacokinetic profile with no AMES toxicity and carcinogenicity.

Alzheimer’s disease (AD) causes dementia and continuous damage to brain cells. Cholinesterase inhibitors can alleviate the condition by increasing communication between the nerve cells and reducing the risk of dementia. In an effort to treat Alzheimer’s disease, we synthesized flurbiprofen-based diamines (1,2 diaminoethane and 1,3 diaminopropane) Zn(II), Cu(II) metal complexes and characterized them by single-crystal X-ray analysis, NMR, (FT)-IR, UV-Vis, magnetic susceptibility, elemental analysis and conductivities measurements. Synthesized diamine metal complexes appeared in ionic forms and have distorted octahedral geometry based on conductivity studies, magnetic susceptibility and electronic studies. Single crystal X-ray diffraction analysis confirmed (2b) Cu(H2O)2(L1)2(L2)2 complex formation. Moreover, we tested all synthesized metal complexes against the cholinesterase enzyme that showed higher inhibition potential. In general, copper metal complexes showed higher inhibitory activities than simple metal complexes with flurbiprofen. These synthesized metal complexes may derive more effective and safe inhibitors for cholinesterases.

In the title compound, C15H14BrNO, the dihedral angle between the aromatic rings is 4.10 (11)° and the molecule is close to planar (r.m.s. deviation for the non-H atoms = 0.053 Å). An intramolecular O—H...N hydrogen bond closes an S(6) ring. In the crystal, very weak C—H...π interactions are observed.

In the title compound, C17H19NO2, the aromatic rings are oriented at a dihedral angle of 59.27 (12)°. In the crystal, inversion dimers linked by pairs of weak C—H...O interactions generate R22(12) loops.

The asymmetric unit of the title compound, C13H11ClN2, contains two geometrically distinct molecules; one molecule is close to planar [dihedral angle between the aromatic rings = 2.44 (18)°] and the other is twisted about the linking hydrazide group [dihedral angle = 14.08 (19)°]. In the crystal, the N—H groups do not form hydrogen bonds and the molecules are linked by weak C—H...π interactions.

In the title compound, C14H10FNO3, the dihedral angle between the two benzene rings is 32.66 (14)°. An S(6) ring motif is formed due to an intramolecular O—H...O hydrogen bond between the hydroxy and carbonyl groups. In the crystal, molecules are consolidated into dimers with R22(8) ring motifs by pairs of O—H...O hydrogen bonds.

In the title compound, C15H10Cl2N4O8, the methylacetate and dichloroanilinic groups are oriented at dihedral angles of 57.73 (8) and 62.44 (4)°, respectively to the dinitro-sustituted benzene ring. S(5) and S(7) rings are formed due to intramolecular N—H...Cl and N—H...O hydrogen bonds, respectively. In the crystal, N—H...O hydrogen bonds link the molecules into C(8) chains along the a axis. Further C—H...O and N—H...O hydrogen bonds link these chains in pairs, forming a polymeric network.

There are two independent molecules in the asymmetric unit of the title compound, C17H20N2, in which the dihedral angles between the aromatic rings are 30.34 (11) and 41.44 (8)°. In the crystal, weak C—H...π interactions may help to establish the packing.

In the title compound, C15H14N2O2, the 2,3-dimethylanilinic and benzaldehyde groups are planar, with r.m.s. deviations of 0.0101 and 0.0241 Å, respectively, and are oriented at a dihedral angle of 11.69 (3)°. The nitro group is inclined to the benzaldehyde group by 34.02 (9)°. The molecule adopts an E configuration about the C=N bond. In the crystal, molecules are linked via C—H...O interactions, giving rise to the formation of zigzag polymeric chains extending along [010]. They are also linked by C—H...π, and π–π interactions [centroid–centroid distance of 3.7185 (11) Å] involving symmetry-related aniline and benzene rings. The H atoms of the ortho-methyl group are disordered over two sites with a refined occupancy ratio of 0.69 (2):0.31 (2).

The asymmetric unit of the title compound, C13H11N3O2, contains two molecules with slightly different conformations: the dihedral angle between the aromatic rings is 13.01 (10)° in one molecule and 14.05 (10)° in the other. Both molecules feature short intramolecular C—H...O contacts, which generate S(6) rings. In the crystal, both molecules form inversion dimers linked by pairs of N—H...O hydrogen bonds, thereby generating R22(16) rings.

In the title compound, C15H14ClN, the conformation about the C=N bond is trans and the dihedral angle between the aromatic rings is 51.48 (4)°. In the crystal, some very weak C—H...π interactions may help to establish the packing.

In the title hydrated molecular salt, 2C7H8NO2+·SO42−·H2O, each cation in the asymmetric unit is stabilized by an intramolecular N—H...O hydrogen bond. The O atoms of the sulfate ion are disordered over two sets of sites with an occupancy ratio of 0.541 (13):0.459 (13), which possibly optimizes the acceptance of N—H...O hydrogen bonds from the cations. The crystal structure also features aromatic π–π stacking [centroid–centroid separation = 3.842 (2) Å] and a C—H...π interaction.

In the molecule of the title compound, 2C4H10N3O2+·SO4−, the cations are planar (r.m.s. deviations = 0.0144 and 0.0236 Å) and oriented at a dihedral angle of 62.30 (4)°. Intramolecular N—H...O hydrogen bonds result in the formation of two planar six-membered rings. The cations are linked to the sulfate ion through intermolecular C—H...O and N—H...O hydrogen bonds, forming an R22(8) ring motif. In the crystal structure, intermolecular N—H...O and C—H...O hydrogen bonds link the molecules into a three-dimensional network.

In the mol-ecule of the title compound, C(14)H(20)N(4)O(3), the five-membered ring adopts an envelope conformation with the O atom displaced by 0.207 (3) Å from the plane of the other ring atoms. Intra-molecular C-H⋯O hydrogen bonds result in the formation of three five-membered rings having envelope conformations. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules, forming R(2) (2)(20) ring motifs, which produce two-dimensional polymeric sheets extending along the b axis. There are also two C-H⋯π inter-actions. The H atoms of one of the methyl groups are disordered over two positions and were refined with occupancies of 0.50.

In the title molecule, C12H10Cl2, the torsion angles Cr—Cr—Cm—Cl around the Cm—Cr bonds have values of −104.1 (4) and −101.9 (4)°, where Cm is a methylene and Cr is a ring C atom. The molecules related by translation along the b axis are arranged into stacks by π–π interactions between unsubstituted and substituted aromatic rings of the naphthalene ring system (centroid–centroid distance = 3.940 Å).

The title compound, C10H10N2O2·H2O, is dimerized by inversion-related intermolecular N—H...O hydrogen bonding. There is an intramolecular N—H...O bond, resulting in a six-membered ring. Each dimer interacts with other dimers through hydrogen bonding with water molecules. The water molecules are linked to each other in a stair-like chain, thus generating two-dimensional polymeric strips. The dimers are also linked to each other through intermolecular C—H...O hydrogen bonding. There are π–π interactions between the aromatic and heterocyclic five-membered rings [centroid–centroid distance 3.8360 (12) Å]. C—H...π interactions also exist between CH2 groups and aromatic rings.

Retraction of Acta Cryst. (2011), E67, m576–m577., The paper by Awan et al. [Acta Cryst. (2011 ▶), E67, m576–m577] is retracted. It has subsequently been shown that the crystal studied was an already known zinc compound, [Zn4Cl4(C2H6NS)4].

In the title molecule, C9H6Cl2N2S, the mean planes of the benzene and thiazole rings make a dihedral angle of 54.18 (8)°. In the crystal, molecules are joined into dimers with an R22(8) ring motif by pairs of N—H...N hydrogen bonds. These dimers are linked by C—H...Cl interactions into layers parallel to (011). The thiazole rings form columns along the c-axis direction, with a centroid–centroid separation of 3.8581 (9) Å, indicating π–π interactions. An intramolecular C—H...S contact also occurs.

In the title compound, C12H14N2S, the dihedral angle between the 1,3,5-trimethylbenzene and 1,3-thiazol-2-amine groups is 73.15 (4)°. In the crystal, inversion dimers linked by pairs of N—H...N hydrogen bonds generateR22(8) loops.

The paper by Awan et al. [Acta Cryst. (2011), E67, m576–m577] is retracted. It has subsequently been shown that the crystal studied was an already known zinc compound, [Zn4Cl4(C2H6NS)4].

There are two geometrically different molecules in the asymmetric unit of the title compound, C14H9Cl2NO3. The 5-amino-2-hydroxybenzoic acid units [r.m.s. deviations of 0.0323 and 0.0414 Å] and 2,6-dichlorobenzaldehyde groups [r.m.s. deviations of 0.0285 and 0.0226 Å] are roughly planar and oriented at dihedral angles of 11.69 (13) and 83.12 (6)° in the two molecules. An intramolecular O—H...O hydrogen bond completes an S(6) ring motif in each molecule. The two molecules form dimers with each other through intermolecular O—H...N and C—H...O hydrogen bonds, completing an R22(8) ring motif. The dimers are interlinked via intermolecular O—H...N and C—H...O hydrogen bonds, forming polymeric sheets.

In the title compound, C15H11NO4, the dihedral angle between the aromatic rings is 23.8 (2)° and an intramolecular O—H...N hydrogen bond generates an S(6) ring. In the crystal, C—H...O hydrogen bonds link the molecules into a three-dimensional network.

In the title compound, C14H11Cl2N, the dihedral angle between the 4-methylanilinic and 2,4-dichlorobenzaldehyde moieties is 7.37 (8)°. In the crystal, C—H...π interactions between the terminal methyl group and a symmetry-related ring of the anilinic group help to establish the packing.

In the title compound, C15H15NO, the almost planar 2,3-dimethylaniline unit and the salicylaldehyde group (r.m.s. deviations of 0.0156 and 0.0109 Å, respectively) are oriented at a dihedral angle of 43.69 (9)° with respect to each other. An S(6) ring motif is formed due to intramolecular O—H...N hydrogen bonding. In the crystal, C—H...π interactions occur between the 2,3-dimethylaniline unit and the salicylaldehyde group, where the CH is from the o-methyl group.

In the title compound, C16H13NO2, the 2,3-dimethylphenyl group and the 1H-isoindole-1,3(2H)-dione group are essentially planar, with r.m.s. deviations of 0.006 and 0.013 Å, respectively, and are oriented at an angle of 78.19 (3)° with respect to each other. In the crystal, weak C—H...O interactions link the molecules, forming a zigzag chain parallel to the b axis. Futhermore, C—H...π interactions are present between the C—H group of isoindole and the 2,3-dimethylphenyl benzene ring. The H atoms of the ortho-methyl group are statistically disordered over two positions. Such disorder might be related to the antagonism between intramolecular steric repulsions and intermolecular C—H...O interactions.

The asymmetric unit of the title compound, C15H14ClNO2, contains two molecules with significantly different conformations: the dihedral angles between the 4-chloroaniline and 3,4-dimethoxyphenyl (excluding C atoms) moieties are 19.68 (7) and 45.54 (4)°. In the crystal, the molecules are linked by C—H...O hydrogen bonds and weak C—H...π interactions.

In the title compound, C13H14N2, the dihedral angle between the aromatic rings is 69.73 (14)°. In the crystal, inversion dimers linked by pairs of N—H...N hydrogen bonds generate R22(10) loops. A weak C—H...π interaction also occurs.

In the title compound, C14H14N2O, the dihedral angle between the aromatic rings is 9.30 (6)°. In the crystal, molecules are linked by C—H...π and N—H...π interactions.

In the title compound, C18H21NO3, the C=N bond has a trans conformation and the benzene rings are oriented at a dihedral angle of 61.32 (6)°. The C atoms of the three methoxy groups are all roughly coplanar with their attached ring [deviations = 0.219 (2), −0.097 (2) and −0.137 (2) Å]. In the crystal, a weak C—H...π interaction may help to establish the packing.

In the title compound, C22H19NO, the 2,3-dimethylanilinic group is planar with an r.m.s. deviation of 0.0226 Å. The phenyl rings with the carbonyl and imine substituents are also planar with r.m.s. deviations of 0.0019 and 0.0048 Å, respectively. These phenyl rings are oriented at dihedral angles of 74.70 (5) and 79.43 (5)°, respectively, with the 2,3-dimethylanilinic group, whereas the dihedral angle between them is 88.28 (4)°. Weak intramolecular C—H...N hydrogen bonding occurs and completes an S(5) ring motif in the molecule. In the crystal, weak π–π interactions are present between the carbonyl-containing phenyl rings at a centroid–centroid distance of 3.5958 (12) Å. C—H...π interactions between the 2,3-dimethylanilinic and the carbonyl-containing phenyl rings are also present, where the C—H group is from the former.

In the title compound, C15H14N2O2, the aromatic rings are oriented at a dihedral angle of 24.52 (5)°. The dihedral angle between the nitro group and its parent benzene ring is 9.22 (16)°. In the crystal, molecules interact through aromatic π—π stacking interactions [centroid–centroid separations = 3.8158 (14) and 3.9139 (14) Å].

In the centrosymmetric title compound, [Ag(4)(C(10)H(2)O(8))](n), the benzene ring has irregular bond lengths but remains planar (r.m.s. deviation 0.0002 Å). The Ag-O bond lengths are in the range 2.153 (3)-2.615 (4) Å. The carboxyl-ate groups are oriented at dihedral angles of 26.4 (5) and 74.9 (4)° to the benzene ring. The coordination behaviour of each carboxyl-ate O atom is different: in one carboxylate, the O atoms are coordinated to a single and two Ag atoms; in the other carboxylate, the O atoms are coordinated to two and three Ag atoms. Non-classical inter-molecular C-H⋯O hydrogen bonding is present in the crystal structure. The title compound forms a three-dimensional polymeric network due to the coordination of the Ag atoms.

The title compound, C(12)H(19)O(4)P, has a distorted tetra-hedral geometry around the P atom. The molecules form dimers with R(2) (2)(10) ring motifs due to inter-molecular O-H⋯O hydrogen bonds. The double-bonded O atom of the phospho-nate group behaves as an acceptor and the hydr-oxy group acts as a donor. Both of the ethyl groups are disordered with occupancies of 0.55:0.45 and 0.725:0.275.

The title compound, C(10)H(12)N(3)O(+)·Cl(-), is a derivative of o-phthaldehyde and methyl-thio-urea. The mol-ecules form dimers through intra- and inter-molecular N-H⋯O hydrogen bonds. The dimers are further linked into chains through one C-H⋯Cl and two N-H⋯Cl hydrogen bonds.

In the title compound, C9H12NO6P, intra­molecular C—H⋯O hydrogen bonds form five- and six-membered rings. In the crystal, inversion dimers lined by pairs of C—H⋯O hydrogen bonds occur with ring motifs R 2 2(10). The O atom of the hydr­oxy group behaves as an accepter and the benzene ring as donor. Adjacent dimers are connected through O—H⋯O links.

In the molecule of the title compound, C11H14N2O2S, the five-membered ring adopts an envelope conformation and an intramolecular N—H...O hydrogen bond occurs. Intramolecular N—H...O, C—H...S and C—H...N hydrogen bonds result in the formation of two five- and one six-membered rings, having twisted conformations. In the crystal structure, intermolecular N—H...O, N—H...S and C—H...S hydrogen bonds link the molecules, forming polymeric sheets. The π–π contacts between the isoindole ring systems, [centroid–centroid distances = 3.5883 (8) and 4.0619 (8) Å] may further stabilize the structure. A C—H...π interactions also occur.

The title molecule, C9H8N2O2, is essentially planar. The crystal structure is stabilized by hydrogen bonding. An intramolecular N—H...O hydrogen bond results in a six-membered ring. Each molecule interacts with two others through N—H...O and C—H...O hydrogen bonding, resulting in the formation of nine-membered rings. These hydrogen bonds generate a two-dimensional polymeric network. There are also π–π interactions between the aromatic and heterocyclic rings [centroid–centroid distance 3.638 (2) Å].

In the title compound, C9H9NO3S, the thia­zine ring adopts a half-chair conformation. The structure is stabilized by an extensive hydrogen-bonded network involving two intra­molecular and three inter­molecular inter­actions.

The title compound, C7H7NO4S, contains an extensive hydrogen-bonded network involving three inter­molecular and three intra­molecular inter­actions that stabilize the structure.

The structure of the title compound, C14H12N2O2S, contains an essentially planar benzisothia­zole ring system which is inclined at 76.52 (5)° with respect to the phenyl ring. The mol­ecules are linked into chains along the b axis by N—H⋯O hydrogen bonds.