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The synthesis of novel metal-organic coordination polymers (MOCP) with the chemical formula [Mn2L (SCN)2(OH)2]3·CH3OH [L = 1,5-bis(pyridine-4-ylmethylene) carbonohydrazide] {1} was accomplished using two different techniques: solvothermal and sonochemical ultrasonic-assisted. An investigation was carried out to examine the impact of various factors such as reaction time, sonication power, temperature, and reactant concentration on the morphology and size of the crystals. Interestingly, it was found that sonication power and temperature did not affect the crystals’ morphology and size. To further analyze the prepared microcrystals of MOCPs, SEM was utilized to examine their surface morphology, and XRD, elemental evaluation composition. The identification of the functional groups present in the prepared Mn-MOCPs was accomplished through the utilization of FT-IR spectroscopy. Subsequently, the calcination of 1 in an air atmosphere at 650 °C led to the formation of Mn3O4 nanoparticles. The geometric and electronic structure of the MOCPs was evaluated using density functional theory (DFT). The utilization of molecular docking methodologies demonstrated that the best cavity of the human androgen receptor possessed an interaction energy of −116.3 kJ mol−1. This energy encompassed a combination of both bonding and non-bonding interactions. The Results showed that steric interaction and electrostatic potential are the main interactions in AR polymer and Mn(II). These interactions in the defined cavity indicated that this polymer could be an effective anti-prostate candidate, because AR is involved in the growth of prostate cancer cells, and these interactions indicated the inhibition of prostate cancer cell growth.

The tropomyosin receptor kinase A (TrkA) family of receptor tyrosine kinases (RTKs) emerge as a potential target for glioblastoma (GBM) treatment. Benzenesulfonamide analogs were identified as kinase inhibitors possessing promising anticancer properties. In the present work, four known and two novel benzenesulfonamide derivatives were synthesized, and their inhibitory activities in TrkA overexpressing cells, U87 and MEF cells were investigated. The cytotoxic effect of benzenesulfonamide derivatives and cisplatin was determined using trypan blue exclusion assays. The mode of interaction of benzenesulfonamides with TrkA was predicted by docking and structural analysis. ADMET profiling was also performed for all compounds to calculate the drug likeness property. Appropriate QSAR models were developed for studying structure–activity relationships. Compound 4-[2-(4,4-dimethyl-2,6-dioxocyclohexylidene)hydrazinyl]-N-(5-methyl-1,3,4-thiadiazol-2-yl)benzenesulfon-amide (AL106) and 4-[2-(1,3-dioxo-1,3-dihydro-2H-inden-2-ylidene)hydrazinyl]-N-(5-methyl-1,3,4-thiadiazol-2-yl)benzenesulfonamide (AL107) showed acceptable binding energies with the active sites for human nerve growth factor receptor, TrkA. Here, AL106 was identified as a potential anti-GBM compound, with an IC50 value of 58.6 µM with a less toxic effect in non-cancerous cells than the known chemotherapeutic agent, cisplatin. In silico analysis indicated that AL106 formed prominent stabilizing hydrophobic interactions with Tyr359, Ser371, Ile374 and charged interactions with Gln369 of TrkA. Furthermore, in silico analysis of all benzenesulfonamide derivatives revealed that AL106 has good pharmacokinetics properties, drug likeness and toxicity profiles, suggesting the compound may be suitable for clinical trial. Thus, benzenesulfonamide analog, AL106 could potentially induce GBM cell death through its interaction with TrkA and might be an attractive strategy for developing a drug targeted therapy to treat glioblastoma.

Two tetranuclear and two mononuclear Cu(II) complexes with arylhydrazones of malononitrile derived ligands (compounds 1–2 and 3–4, respectively), one trinuclear Co(II/III) complex with an arylhydrazone of acetoacetanilide (5) and one tetranuclear Zn(II) complex of 3-(2-carboxyphenyl-hydrazone)pentane-2,4-dione (6) were screened as potential catalysts in the peroxidative oxidation of cyclohexane by aqueous H2O2 in acetonitrile. The best results were attained in the presence of pyrazine-2-carboxylic acid (PCA) with 1 (26% yield, TON = 52.0) and with 2 (24%, TON = 48.0) after 4 h at 40 °C. In the presence of complexes 5 and 6, no oxygenated products were detected in the studied conditions. The employment of non-conventional conditions like supercritical carbon dioxide (scCO2) as reaction medium or microwave (MW) irradiation was assessed for complexes 1 and 2. After 6 h in acetonitrile–scCO2, at 50 °C and with HNO3 as promoter, only 17% yield was achieved using 1 as catalyst, and 21% using 2. Total yields of oxygenates up to 14 (with 1) and 13% (2) and TOFs of 56.0 and 52.0 h−1, respectively, were obtained working under MW irradiation at 70 °C and for the much shorter time of 0.5 h.

A novel and efficient approach to the synthesis of 2-vinylbenzylamines is reported. This involves obtaining 2-vinylbenzylamine ligands from tetrahydroisoquinoline by alkylation and reduction followed by the Hofmann cleavage. The resultant 2-vinylbenzylamines allowed us to obtain new Hoveyda–Grubbs catalysts, which were thoroughly characterised by NMR, ESIMS, and X-ray crystallography. The utility of this chemistry is further demonstrated by the tests of the novel catalysts (up to 10−2 mol %) in different metathesis reactions such as cross metathesis (CM), ring-closing metathesis (RCM) and ring-opening cross metathesis (ROCM).

The Special Issue on “Advanced Research in Halogen Bonding” is a collection of 17 original articles reporting the results of theoretical and experimental studies that provide new insights into this fascinating intermolecular interaction [...]

A series of 4,5-dibromo-2-(4-substituted phenyl)hexahydro-3a,6-epoxyisoindol-1(4H)-ones were synthesized by reaction of the corresponding 2-(4-substituted phenyl)-2,3,7,7a-tetrahydro-3a,6-epoxyisoindol-1(6H)-ones with [(Me2NCOMe)2H]Br3 in dry chloroform under reflux for 3−5 h. In contrast to the 4-F and 4-Cl substituents, one of the bromine atoms of the isoindole moiety behaves as a halogen bond donor in the formation of intermolecular halogen bonding in the 4-H, 4-Br and 4-I analogues. Not only intermolecular hydrogen bonds, but also Ha⋯Ha and Ha⋯π types of halogen bonds in the 4-H, 4-Br, and 4-I compounds, contribute to the formation of supramolecular architectures leading to 2D or 3D structures.

Nanospheres of a new coordination polymer {[Cd2(µ-HL)(µ-L)(NO3)3(H2O)]·H2O}n (1) were easily prepared by a sonochemical method from cadmium(II) nitrate and HL (HL, pyridine-2-carboxaldehyde isonicotinoyl hydrazone) in ethanol. Single crystals of 1 were also obtained using a branched tube method. The crystal structure of 1 indicates that the µ-HL/µ-L− blocks act as linkers between the Cd(II) centers, assembling them into 1D tooth-shaped interdigitated chains, which are further interlinked into a complex 3D H-bonded network with a rare hms (3,5-conn) topology. Nanoparticles of 1 were characterized by elemental analysis, FT-IR spectroscopy, and powder X-ray diffraction (XPRD), while their spherical morphology was confirmed by transmission electron microscopy (TEM). Furthermore, in the presence of a surfactant, the thermolysis of sonochemically generated nanoparticles of 1 led to the formation of cadmium oxide nanospheres (cubic CdO) with an average diameter of 10 nm. This study extends the application of sonochemical synthetic methods for the generation of phase pure nanoparticles of coordination polymers and their thermolysis products.

The title compound, C21H18N2O4, obtained as a racemate, contains a novel heterocyclic system, viz. isoindolo[1,2-c]pyrrolo[1,2-a][1,4]benzodiazepine. The central diazepane ring has a distorted boat conformation with two phenylene-fused and one methine C atom deviating by 0.931 (1), 0.887 (1) and 0.561 (1) Å, respectively, from the mean plane of the rest of the ring. The γ-lactone ring has an envelope conformation, with the C atom opposite to amide bond deviating by 0.355 (1) Å from its plane. In the crystal, molecules form centrosymmetric dimers through pairs of C—H...O hydrogen bonds.

Reaction of 2-chloro-2-(diethoxymethyl)-3-substitutedoxirane or 1-chloro-1-(substituted) -3,3-diethoxypropan-2-one with pyridine-2-thiol in EtOH at 25 °C yields 3-(diethoxymethyl)-3-hydroxy-2-substituted-2,3-dihydrothiazolo[3,2-a]pyridin-4-ium chlorides, which subsequently, in MeCN at 85°C, transforms into ring-opening products, 2-((2-carboxy-1-(substituted) -2-hydroxyethyl)thio)pyridin-1-ium chlorides. The tetrel (C···O) and chalcogen (S···O) bonds are found in the structures of 5 and 6, respectively. Compound 6 is also present in halogen bonding with a short O···Cl distance (3.067 Å). Both molecules are stabilized in crystal by tetrel, chalcogen, and multiple charge-assisted hydrogen bonds.

The title compound, [Fe(C7H9N2)2], crystallizes with two crystallographically independent molecules in the unit cell. These represent the chiral atropoisomers distinguished by the mutual arrangement of the two acetyl–hydrazone groups with a cis conformation of the C=N bonds. The two cyclopentadienyl (Cp) rings are planar and nearly parallel, the tilt between the two rings being 3.16 (16)° [4.40 (18)° for the second independent molecule]. The conformation of the Cp rings is close to eclipsed, the twist angle being 0.1 (2)° [3.3 (2)°]. The two acetyl–hydrazone substituents are also planar and are inclined at 13.99 (15)/9.17 (16)° [6.83 (17)/14.59 (15)°] relative to the Cp rings. The Fe—C bond lengths range from 2.035 (3) to 2.065 (2) Å, with an average of 2.050 (3) Å [2.036 (3) to 2.069 (2), average 2.046 (3) Å], which agrees well with those reported for most ferrocene derivatives. In the crystal, the molecules form dimers via two strong N—H...N hydrogen bonds. The dimers are linked into a three-dimensional framework by weak N—H...N hydrogen bonds.

In the title compound, [Ni(C8H14N6S2)], the NiII ion is coordinated by N2S2 donor atoms of the tetradentate thiosemicarbazone ligand, and has a slightly distorted square-planar geometry. In the crystal, inversion-related molecules are linked via pairs of N—H...N and N—H...S hydrogen bonds, forming R22(8) ring motifs. Molecules are further linked by slightly weaker N—H...N, N—H...S and C—H...S hydrogen bonds, forming two-dimensional networks which lie parallel to the bc plane.

In the title compound, C24H22N2O2, the central imidazole ring makes dihedral angles of 49.45 (8), 88.94 (9) and 19.43 (8)° with the benzene ring and the two phenyl rings, respectively. The dihedral angle between the phenyl rings is 77.86 (9)°, and they form dihedral angles of 49.06 (9) and 67.31 (8)° with the benzene ring. In the crystal, molecules are linked by O—H...N hydrogen bonds, forming chains along the b axis. These chains are connected by C—H...O hydrogen bonds, forming a two-dimensional network parallel to (100). In addition, C—H...π interactions are also observed. The terminal C and O atoms of the ethanol group are disordered over two sets of sites with an occupancy ratio of 0.801 (5):0.199 (5).

In the title compound, C21H24BrNO4, the dihedral angle between the heterocyclic ring and the pendant aromatic ring is 80.20 (13)°. The hexahydroquinone [i.e. the one with the C=O group] ring adopts a sofa conformation. An intramolecular O—H...O hydrogen bond generates an S(6) ring motif. The ethyl group is disordered over two sets of sites with a refined site occupancy ratio of 0.633 (10):0.366 (10). In the crystal, molecules are linked by N—H...O interactions, forming chains parallel to [101]. There are no significant C—H...π or π–π interactions in the crystal structure.

In the title compound, C21H25NO3, the hydropyridine ring that constitutes a part of the hexahydroquinoline fused-ring system adopts a sofa conformation; the methine C atom deviates from the least-squares plane defined by the remaining five non-H atoms (r.m.s. deviation = 0.088 Å) by 0.454 (3) Å. The phenyl ring is aligned at 85.5 (1)° with respect to this mean plane. In the crystal, adjacent molecules are linked via an N—H...O hydrogen bond, involving the amino group and the carbonyl O atom of the fused-ring system, forming chains running along [100]. The ethyl group is disordered over two positions in a 0.609 (6):0.391 (6) ratio.

The cyclohexene ring that constitutes a part of the tetrahydroxanthene fused-ring system of the title compound, C23H26O4, adopts a flattened half-chair conformation that approximates an envelope conformation (in which the methylene C atom bearing the two methyl substituents represents the flap) as five of the six atoms lie approximately on a plane (r.m.s. deviation = 0.020 Å). The mean plane of the cyclohexene ring with the hydroxy substituent is approximately perpendicular to the mean plane of the tetrahydroxanthene system. In the crystal, adjacent molecules are linked by O—H...Ocarbonyl hydrogen bonds into a chain running along the b axis.

The CuII atom in the title compound, [Cu(C12H11N2O4)2(C10H14N2O)(H2O)]n, lies in a square plane defined by the O atoms of the carboxylate ions, the N atom of the N-heterocycle and the water molecule. Coordination by an amido O atom of an adjacent N-heterocycle in the apical direction leads to a polymeric chain running along [01-1]. The chain motif is consolidated by hydrogen bonds involving the water molecule; the water molecule is a hydrogen-bond donor to the free carbonyl atoms of the carboxylate ions. Intramolecular N—H...O hydrogen bonds also occur.

In the title compound, C13H14N2OS, four C atoms of the phenyl ring are disordered over two sets of sites in a 0.60 (3):0.40 (3) ratio. The heterocyclic ring is essentially planar (r.m.s. deviation = 0.017 Å) and forms dihedral angles of 82.0 (2) and 79.3 (3)°, respectively, with the major and minor occupancy components of the phenyl ring. The crystal packing features N—H...O hydrogen bonds, which link the molecules into C(6) chains running parallel to the b axis.

In the title compound, [Cu(C12H11N2O4)2(C10H14N2O)2(H2O)2], the CuII atom lies on a center of inversion and is coordinated by carboxylate O atoms, pyridine N atoms and two water molecules in an elongated octahedral geometry. The pyridine ring is oriented at a dihedral angle of 74.83 (12)° with respect to the benzene ring. Intramolecular O—H...O and N—H...O hydrogen bonding is observed. The water molecule is a hydrogen-bond donor to the carbonyl O atom of an adjacent carboxylate group, generating a chain running along the a axis. One of the ethyl groups is disordered over two sets of sites in a 0.787 (5):0.213 ratio.

The C=C bond in the title compound, C14H15NO4, is in an E configuration. With the exception of the methyl C atoms, the non-H atoms of the molecule all lie approximately on a plane (r.m.s. deviation = 0.096 Å). π–π stacking is observed between parallel benzene rings of adjacent molecules, the centroid–centroid distance being 3.7924 (8) Å.

In the title compound, C6H12N2O2S, the heterocyclic ring has a sofa conformation. The molecular conformation is stabilized by an intramolecular O—H...O hydrogen-bond interaction with graph-set motif S(6). In the crystal, molecules are linked by O—H...S, N—H...S and N—H...O hydrogen-bond interactions, forming an extended two-dimensional framework parallel to the ac plane.

In the title compound, C24H35NO2, the planes of the two aromatic rings form a dihedral angle of 72.76 (4)°. In the crystal, molecules are linked by O—H...O and O—H...N hydrogen-bond interactions, forming an extended two-dimensional framework parallel to the ab plane.

In the title compound, C8H10N2, the cyclohexane ring adopts a chair conformation. he crystal structure of the previously reported monoclinic modification have intramolecular CN...CN and C—H...N interactions. These types of interaction are not present in this new modification whose crystal structure is built up by van der Waals interactions.

In the title compound, C16H25NO, the N-tert-butylpropanamide fragment is essentially planar, with the exception of two C atoms of the tert-butyl group (r.m.s. deviation = 0.005 Å), forming a dihedral angle of 84.09 (10)° with the plane of the mesityl fragment (r.m.s. deviation = 0.002 Å). The crystal packing is stabilized by an intermolecular N—H...O hydrogen bond, which links the molecules into chains with graph-set notation C(4) running parallel to the c axis.

In the title compound, [Cu(C8H4F3O2S)2(C10H14N2O)], the CuII atom exists in a distorted CuNO4 square-pyramidal geometry; the metal atom lies above a square plane defined by four O atoms of the two chelating anionic ligands, displaced in the direction of the axial occupant, the pyridine N atom, by 0.179 (1) Å. Weak intermolecular C—H...O and C—H...F hydrogen bonding is present in the crystal structure. One thienyl ring is disordered over two orientations in an occupancy ratio of 0.69 (1):0.31.

In the title compound, C20H26N2OS, four non-H atoms of the thiourea unit are approximately planar (r.m.s. deviation = 0.005 Å); the phenyl and benzene rings are twisted out of this plane by 28.55 (7) and 60.00 (7)°, respectively. An intramolecular N—H...O hydrogen bond occurs. The hydroxy group is hydrogen bonded to the double-bond S atom of an inversion-related molecule, generating a hydrogen-bonded dimer in the crystal structure.

The six-membered oxacyclohexene ring of the title compound, C13H14N2O2S, is fused with the benzene ring and the quarternary C atom lies above the plane of the benzene ring by 0.229 (8) Å, whereas the methine C atom (which bears the acetyl substituent) lies below this plane by 0.595 (8) Å. The oxacyclohexene ring is also fused with the sofa-shaped 2,6-diazacyclohexanone ring. The methine C atom that belongs to both six-membered rings lies above the mean plane of the other five atoms (r.m.s. deviation = 0.077 Å) by 0.759 (5) Å. In the crystal, N—H...S hydrogen bonds link adjacent molecules into a linear chain.

The dihydropyridine ring in the title compound, C26H32BrNO4, adopts an envelope conformation with the methine C atom representing the flap. The cyclohexenone rings also adopt envelope conformations. The phenolic hydroxy group forms an intramolecular hydrogen bond to one of the two keto O atoms. Intermolecular weak C—H...O hydrogen bonding is present in the crystal structure. The hydroxypropyl group is disordered over two sets of sites with an occupancy ratio of 0.636 (6):0.364 (6).

In the title molecule, C39H45NO6, the two tetramethyloctahydroxanthen-1,8-dione substituents are arranged approximately parallel to each other and approximately perpendicular to the plane of the pyridine ring. The six-membered xanthene rings adopt flattened boat conformations with the O and methine C atoms deviating from the plane of the other four atoms.

The methylaminopropyl chain in the title compound, C13H21NO, adopts an extended zigzag conformation and the N atom shows a trigonal coordination. The N atom acts as hydrogen-bond acceptor to the hydroxy group of an adjacent molecule, generating a helical chain running along the b axis. The amino H atom is not involved in hydrogen bonding.

The pyridine ring in the title compound, C39H47NO7·0.5C2H5OH·0.5 H2O, is connected to one 3,3,6,6-tetramethyl-1,8-dioxoxanthenyl and one 4a-hydroxy-3,3,6,6-tetramethyl-1,8-dioxodecahydroxanthenyl substituent in the 2- and 6-positions of the ring. In the former substituent, the six-membered xanthenyl ring adopts a flattened envelope conformation (with the methine C atom as the flap) while in the latter, the six-membered xanthenyl ring adopts a twisted envelope conformation (with the C atom bearing the hydroxy group representing the flap). The hydroxy H atom forms an intramolecular hydrogen bond to the pyridyl N atom. An ethanol solvent molecule is disordered with respect to a water molecule in a 1:1 ratio. The water molecule itself is disordered over two positions of equal occupancy.

In the title 2-propanol derivative, C17H27ClO2, the two tert-butyl groups both have one methyl C atom lying in the plane of the aromatic ring. In the crystal, the phenol group forms a hydrogen bond to the hydroxy O atom belonging to the alkyl substituent of an adjacent molecule, forming a chain along the ac diagonal. The Cl atom is disordered over two positions in a 0.73 (4):0.27 (4) ratio.

In the title comound, C8H8N4S, one of the two independent molecules is essentially planar (r.m.s. deviation = 0.025 Å), while the other is slightly buckled (r.m.s. deviation = 0.131 Å) with the guanidine unit bent out of the plane of the fused-ring system by 16.8 (1)°. In the crystal, intermolecular N—H...N hydrogen bonds between the two independent molecules give rise to a hydrogen-bonded dimer. Addtional weak intermolecular N—H...N hydrogen bonds connect these dimers into chains along [010]. An intramolecular N—H...N hydrogen bond is also observed in each independent molecule.

The C=C double-bond in the title compound, C13H13ClO3, has a Z configuration. The aliphatic substituents at one end of the double bond, i.e. the CH3CO– and C2H5O2C– groups, are aligned at 82.1 (3)° with respect to each other.

The organic molecule in the title hydrate, C9H9N3O3·H2O, was obtained by the condenstation of salicylic aldehyde with urea in acetonitrile. The oxazine ring adopts a slightly distorted sofa conformation, with the N atom deviating from the plane passing through the other atoms of the ring by 0.267 (2) Å. The crystal structure displays intermolecular N—H...O and O—H...O hydrogen bonding.

The title compound, C26H28N2O9·1.5H2O, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as a sesquihydrate with the O atom of one of the two independent water molecules occupying a special position on a twofold axis. The organic molecule comprises a fused pentacyclic system containing two five-membered rings (cyclopentane and tetrahydrofuran) and three six-membered rings (piperidinone, tetrahydropyridine and benzene). The five-membered rings have the usual envelope conformations, and the central six-membered piperidinone and tetrahydropyridine rings adopt boat and sofa conformations, respectively. In the crystal, there are three independent O—H...O hydrogen bonds, which link the organic molecules and water molecules into complex two-tier layers parallel to (001). The layers are further linked into a three-dimensional framework by attractive intermolecular carbonyl–carbonyl interactions.

The title compound, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as an ethanol monosolvate, C20H21NO8·C2H6O. The title molecule comprises a fused tricyclic system containing two five-membered rings (cyclopentane and tetrahydrofuran) in the usual envelope conformations and one six-membered ring (piperidinone) adopting a flattened twist–boat conformation.

The title compound, C27H29NO11, is a product of the tandem `domino' Diels–Alder reaction. The molecule comprises a fused hexacyclic system containing four five-membered rings (two dihydrofuran and two tetrahydrofuran) in the usual envelope conformations and two six-membered rings (tetrahydropyridinone and piperidine) adopting slightly flattened boat and chair conformations, respectively. The dispositions of the carboxylate substituents relative to each other are determined by both steric reasons and intermolecular C—H...O hydrogen bonding and attractive antiparallel C=O...C=O interactions [C...O = 2.995 (2) Å].