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A new organic material (E)-1-(3,4-dimethoxyphenyl)-3-(4-(trifluoromethyl)phenyl)prop-2-en-1-one (DPTF), belonging to chalcone family, exhibiting third-order non-linear optical properties has been synthesised and grown as single crystals, by slow evaporation technique at room temperature. The grown crystal was subjected to single-crystal X-ray diffraction analysis in order to establish their crystal structure. The DPTF crystal belongs to the triclinic crystal system (a = 8.0368 Å,b = 10.4345 Å,c = 10.4560 Å andα = 114.1645°,β = 96.5748°,γ = 101.4285°) with centrosymmetric space group. The functional groups present in DPTF molecule were identified using FTIR spectral studies. The linear optical properties, direct and indirect transition energy gaps were determined using UV–visible spectral data. The melting point and thermal stability of DPTF have been established through thermo-gravimetric and differential scanning calorimetric technique. The non-linear optical properties have been studied using single-beam Z-scan technique. The coefficient of non-linear absorption and non-linear refractive index are found to be 5.11 cm/GW and −2.48 × 10−11 esu, respectively. The DPTF molecule exhibits optical power limiting property. [ABSTRACT FROM PUBLISHER]

The first syntheses of indolopterin and indoloquinoxaline, two important and dissimilar diheterocycles linking C-2 of indole with C-6 of pterin (significant positions for showing biological activity), and quinoxaline, respectively, have been achieved based on two classical reactions. The introduction of a keto methyl group on to the 6-position of pterin and quinoxaline followed by Fischer indole synthesis led to these target diheterocycles. These indole-substituted diheterocycles will significantly increase the electron density on the pterin-5-N and quinoxazoline-2-N, which may change the redox properties of pterin and quinoxaline, and also the electron-withdrawing pterin or quinoxazoline should make the indole NH more acidic. [ABSTRACT FROM PUBLISHER]

Polysulfone and polyphenylsulfone-blend ultrafiltration membranes of different compositions were prepared by the phase inversion method, with and without hydrophilic additive poly (ethylene glycol) 1,000 (PEG). The membrane morphology was studied using scanning electron microscope, which displayed the asymmetric structure of the membrane. The hydrophilicity of the membranes was measured by contact angle, porosity, water uptake, and permeability studies. The blend membrane showed enhanced permeability, hydrophilicity, and antifouling property as compared to the pristine polymer membrane. The pure water flux of the membrane, which was blended with PEG additive was relatively higher than the blend membranes without the additive. The flux recovery ratio (FRR) was measured to study the antifouling property. The membranes with PEG additive exhibited better antifouling property with maximum FRR of 72.84%. The heavy metal rejection by the membrane was carried out by complexing the metal ions with polyethyleneimine, which exhibited highest rejection of 99.48 and 95.5% of Pb2+ and Cd2+, respectively. [ABSTRACT FROM AUTHOR]

Three carbazole based benzimidazole derivatives exhibiting the effect of intramolecular charge transfer (ICT) caused by the donor–acceptor interaction between their carbazole and benzimidazole units were synthesized. Their photophysical properties were systematically investigated in various solvents with different polarities. Positive solvatofluorochromic effects were observed with the change of solvent from non-polar to polar for all of the three dyes. The synthesized compounds presented proton-induced absorption as well as ratiometric emission changes, indicating that these compounds might be used as proton sensors. The dyes in their solid state are also able to detect acid vapours. The optimized structures of the dyes and their protonated forms were calculated by density functional theory calculations. [ABSTRACT FROM AUTHOR]

A benzothiazole conjugated quinoline derivative appended with rhodamine-6G acts as an efficient FRET-based single molecular switch for Fe3+. The structure of the probe was confirmed through its single crystal X-ray study. The sensor demonstrates an immediate fluorescence ratiometric response specific towards Fe3+ which also allows facile naked-eye detection of Fe3+. The probe is highly selective only towards Fe3+ in comparison to other environmentally important cations, including Fe2+. Moreover, the detection limit was found to be in the 10−8 M range for the recognition of Fe3+. [ABSTRACT FROM AUTHOR]

The X-ray crystal structure of 3-(2-(4-morpholinophenyl)-2-oxoethyl)-5,5-diphenylimidazolidine-2,4-dione (2) [C27H25N3O4: MF = 455.50, monoclinic,P21/c,a =6.2038 (2) Å,b= 20.8905 (6) Å,c= 18.3361 (6) Å,b= 97.594 (2)ο,V= 2355.53 Å3,Z= 4,Dcalc= 1.284 Mg m−3, λ = 1.54178 Å] was determined. The crystal packing confirmed the occurrence of two conformers of opposite conformation. Conformational aspects of compound2have pointed out two factors that determine the conformation of the system under investigation: first, the intermolecular hydrogen bonding of the crystal packing, which stabilizes and favors the occurrence of two independent molecules, and the second factor is the steric hindrance among substituents. [ABSTRACT FROM PUBLISHER]

A series of heterocyclic chalcone (3a–e,5,7) were synthesized and characterized by Infrared,1H and13C nuclear magnetic resonance, and mass spectra. Crystal structure of 1-(4-iodophenyl)-3-(5-methylfuran-2-yl)prop-2-en-1-one was determined using single crystal X-ray diffraction. All the synthesized compounds were evaluated for their cytotoxic activities on MDA MB 231 and CHO cell by using MTT assay. Compound3cshowed good cytotoxic effect on MDA MB 231 with IC50values of 9.8 µg/mL. [ABSTRACT FROM PUBLISHER]

Based on excited state intramolecular proton transfer (ESIPT) and chelation enhanced fluorescence (CHEF) mechanisms, a new fluorescence ratiometric probe for Al3+ was designed and synthesized, and its structure was confirmed through single crystal X-ray study. This probe is capable of showing excited state intramolecular proton transfer through two different pathways. The introduction of Al3+ in a mixed aqueous solution with the probe results in an abrupt change in the photophysical properties of the probe. A ratiometric emission profile was observed in the presence of Al3+. Interestingly, the presence of other metal ions (especially trivalent ions, e.g. Fe3+, Cr3+, Ga3+ and In3+) do not perturb the fluorescence intensity of the probe (except Cu2+ and Pb2+, where slight changes were noticed). This indicates that the probe shows high affinity towards Al3+. The ratiometric sensing phenomenon may be explained by the presence of two different mechanisms, namely, excited state intramolecular proton transfer and chelation induced enhanced fluorescence, which are demonstrated by the probe in presence of Al3+ in the excited state. The complexation of the probe with Al3+ inhibits excited state intramolecular proton transfer while the chelation induced enhanced fluorescence mechanism becomes dominant. The probe efficiently detected the cellular uptake of Al3+, which is demonstrated here with human blood-cell imaging. Moreover, the detection limit was found to be 6.72 × 10−8 M. [ABSTRACT FROM AUTHOR]

Crystals of 7,11- bis(2,4-dichlorophenyl)-2,4-dimethyl-2,4-diazaspiro[5.5]undecane -1,3,5,9-tetraone were grown in polar solvents and subjected to single crystal X-ray diffraction. The molecular crystal is Triclinic, P-1, a= 8.3734 (19) Å, b= 12.382 (3) Å, c= 12.871 (3) Å, α= 66.639 (7) , β= 85.148 (7) , γ= 70.690 (6) , V= 1154.5 (5)Å , Z= 2, D = 1.519 g cm . The optimized molecular structure of the studied compound using B3LYP/6-311G(d,p) method showed good agreement with the X-ray structure. The electronic and spectroscopic properties of the title compound were predicted. The NBO calculations were used to calculate the natural atomic charges at the different atomic sites as well as the intramolecular charge transfer (ICT) interactions among the most significant natural orbitals. The high LP(N) → BD*(2)C-O ICT interaction energies indicate strong electron delocalization from the lone pair of the N-atoms of the pyrimidinetrione ring to the adjacent carbonyl groups. In contrast, the small LP(O) →BD*(1)C-H stabilization energies (E ) indicated weak C-H-O interactions. Experimentally, the studied compound showed the most intense electronic transition band at 232 nm which is calculated using TD-DFT method as a shoulder at 231.3 nm (f =0.0832) and it belongs to H-3/H-1 → L+1 and H-2 → L+2 excitations. The GIAO calculated H and C NMR chemical shifts showed good correlations with the experimental data. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The synthesis and spectral characterization of the ( E)-3-benzylideneindolin-2-one is reported. The compound crystallized in the monoclinic system with space group P2/ n with cell coordinates a= 3.9849 (2) Å, b= 22.2236 (9) Å, c= 12.2501 (5) Å, β= 95.0535 (12) , V=1080.64 (8) Å , and Z= 4. In the crystal, molecules are packed in chains formed via weak intermolecular C13-H13A ⋯O1 and N1-H1N1 ...O1 hydrogen bonding. The relative stabilities of the two tautomeric isomers of 3 are calculated by DFT/B3LYP method using 6-311G(d,p) basis set in gas phase and in solution. The quantum chemical calculations, NMR studies and the XRD analyses showed that the keto form T0 is the only form that could exist in gas, solution and solid phases respectively. The calculated geometric parameters of the dimer molecule showed better agreement with the XRD data than those obtained for single isolated molecule. This shed light on the effect of intermolecular interactions on the calculated geometric parameters. MEP study showed that, the O-atom and the NH proton are the most reactive H-acceptor and H-donor sites, respectively. The N-H...O H-bonding interactions increased the negative charge at the O-atoms and the positive charge of the NH protons compared to the monomer unit. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Three series of isatin derivatives [3-hydrazino, 3-thiosemicarbazino, and 3-imino carboxylic acid derivatives] were synthesized employing microwave irradiation. The prepared compounds were characterized by FT-IR, NMR, elemental analysis, and X-ray crystallography for derivatives 5b. The synthesized compounds were screened for antimicrobial activity against selected bacteria and fungi. The results revealed that the N-alkyl isatin derivatives were biologically active with different spectrums activity. Most of the 3-hydrazino and 3-thiosemicarbazino isatin derivatives were biologically inactive and generally the active derivatives showed weak to moderate activity mainly against Gram-positive bacteria. The imino isatin carboxylic acid derivatives (2-[4-(1-benzyl-5-bromo-2-oxoindolin-3-ylideneamino) phenyl]acetic acid, 5d) showed promising activity against all tested Gram-positive bacteria and against fungal pathogens. [ABSTRACT FROM AUTHOR]

A facile approach for the preparation of an organic antifouling polymer membrane has been developed using low molecular weight organic acids as additives. The presence of these additives in the membrane was analysed by FTIR spectroscopy. The properties of the modified membranes were investigated in terms of contact angle, water uptake capacity, SEM and AFM analysis. These additives exerted a strong impact on the rheological properties of the casting solution, thereby altering the membrane morphology, surface roughness, water flux and the hydrophilicity of the membranes, as compared to those of the pristine polyetherimide (PEI) membrane. The organic antifouling properties of the modified membrane were analysed by filtering both bovine serum albumin (BSA) and humic acid solutions. The results showed that the additives exhibited a remarkable improvement in the antifouling properties (FRR of 72%) and a humic acid rejection of up to 86%. These outcomes offer new insights into the use of cheaper and readily available organic acids as additives, compared to the traditional, synthetic polymer materials as additives in membrane preparation. [ABSTRACT FROM AUTHOR]

The title compound tetraphenylborate salt of bambuterol (Bambec), N-(2-(3,5-bis((dimethylcarbamoyl)oxy)phenyl)-2-hydroxyethyl)-2-methylpropan-2-aminium tetraphenylborate ( 4), was prepared in 73 % yield by the reaction of 5-(2-( tert-butylamino)-1-hydroxyethyl)-1,3-phenylene bis(dimethylcarbamate) hydrochloride (bambuterol hydrochloride) ( 2) with sodium tetraphenylborate ( 3) in deionized water, at ambient temperature, through anion exchange reaction. The structure of the title borate salt was characterized by IR, mass and H NMR analyses. Colorless crystals of 4 suitable for an X-ray structural analysis were obtained by slow evaporation from acetonitrile. Compound 4 crystallizes in the monoclinic, space group P2/ c, with a = 8.8931 (2) Å, b = 20.4639 (6) Å, c = 21.4393 (6) Å, β = 93.640 (2)°, V = 3893.81 (18) Å, Z = 4. Graphical Abstract: Synthesis, characterization and X-ray structure of tetraphenylborate salt of bambuterol (Bambec), the drug for the treatment of asthma, bronchospasm, emphysema, and chronic obstructive pulmonary disease. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The phosphatase domain (PA3346PD) of the response regulator PA3346 modulates the downstream anti-anti-σ factor PA3347 to regulate swarming motility in Pseudomonas aeruginosa PAO1. PA3346PD, which comprises the protein phosphatase 2C domain (PP2C), is classified as a Ser/Thr phosphatase of the Mg2+- or Mn2+-dependent protein phosphatase (PPM) family. The recombinant PA3346PD, with molecular mass 26 kDa, was overexpressed in Escherichia coli, purified on an Ni2+-NTA agarose column and crystallized by the sitting-drop vapour-diffusion method. X-ray diffraction data were collected from PA3346PD crystals to a resolution of 2.58 Å and the crystals belonged to space group I4132 or I4332, with unit-cell parameter a = 157.61 Å. Preliminary analysis indicates the presence of a monomer of PA3346PD in the asymmetric unit with a solvent content of 58.4%. [ABSTRACT FROM AUTHOR]

The reaction of 2-isonicotinoyl- N-cyclohexyl/arylhydrazinecarbothioamide ( 2a- r) with sodium hydroxide, in each case, a single product was obtained. The structures of the compounds were confirmed on the basis of their elemental analysis and spectral data. The single crystal X-ray analysis confirmed the structure of these products as N-4-cyclohexyl/aryl-5-(pyridine-4-yl)-2,4-dihydro-3 H-1,2,4-triazole-3-thiones ( 3a- r). The in vitro antitumor activity of compounds was screened against three cell lines; BEL-7402, HUH-7 and HepG2 human hepatoma using MTT assay. Sorafenib (50 µM) was used as a positive control. The results of the MTT-dye reduction assay indicated that most of the compounds exert potent cytotoxic/antiproliferative effect in a time and dose-dependent manner via induced apoptosis of HepG2 cells. Results also showed that the tested compounds could significantly enhance the activity of caspase-3 which plays a very important role as the central effecter during apoptosis. The effect of different substitutions on the aromatic portion on the activity was found to be in the following order CH > OCH > I > SONH > OCH > CH > NO > Cl > CHCONH. [ABSTRACT FROM AUTHOR]

10-Formyltetrahydrofolate dehydrogenase (FDH), which is composed of a small N-terminal domain (Nt-FDH) and a large C-terminal domain, is an abundant folate enzyme in the liver and converts 10-formyltetrahydrofolate (10-FTHF) to tetrahydrofolate (THF) and CO2. Nt-FDH alone possesses a hydrolase activity, which converts 10-FTHF to THF and formate in the presence of β-mercaptoethanol. To elucidate the catalytic mechanism of Nt-FDH, crystal structures of apo-form zNt-FDH from zebrafish and its complexes with the substrate analogue 10-formyl-5,8-dideazafolate (10-FDDF) and with the products THF and formate have been determined. The structures reveal that the conformations of three loops (residues 86-90, 135-143 and 200-203) are altered upon ligand (10-FDDF or THF) binding in the active site. The orientations and geometries of key residues, including Phe89, His106, Arg114, Asp142 and Tyr200, are adjusted for substrate binding and product release during catalysis. Among them, Tyr200 is especially crucial for product release. An additional potential THF binding site is identified in the cavity between two zNt-FDH molecules, which might contribute to the properties of product inhibition and THF storage reported for FDH. Together with mutagenesis studies and activity assays, the structures of zNt-FDH and its complexes provide a coherent picture of the active site and a potential THF binding site of zNt-FDH along with the substrate and product specificity, lending new insights into the molecular mechanism underlying the enzymatic properties of Nt-FDH. [ABSTRACT FROM AUTHOR]

A new visible-light-excitable fluorescence ratiometric probe for OCl- has been developed based on a triphenylamine-diamiomaleonitrile (TAM) moiety. The structure of the dye was confirmed by single-crystal X-ray analysis. It behaves as a highly selective and sensitive probe for OCl- over other analytes with a fast response time (~100 s). OCl- reacts with the probe leading to the formation of the corresponding aldehyde in a mixed-aqueous system. The detection limit of the probe is in the 10-8m range. The probe (TAM) also exhibits solvatofluorochromism. Changing the solvent from non-polar to polar, the emission band of TAM largely red-shifted. Moreover, the probe shows an excellent performance in real-life application in detecting OCl- in human blood cells. The experimentally observed changes in the structure and electronic properties of the probe after reaction with OCl- were studied by DFT and TDDFT computational calculations. [ABSTRACT FROM AUTHOR]

Five 2-aminochalcone derivatives [R = H(1), R = OCH2CH3(2), R = 2,4,5-OCH3(3), R = 3,4,5-OCH3(4), and R = thiophene(5)] were synthesized and characterized by1H NMR, FT-IR, and UV-Vis spectroscopy. Crystal structure of2was also determined by single crystal X-ray diffraction. Compound2crystallizes in a monoclinic P21/n space group with the unit cell parameters a = 32.804(7) Å, b = 4.9972(11) Å, c = 21.7173(3) Å, β = 128.440(4)°, V = 2788.4(10) Å3, and Z = 8. There are two molecules in an asymmetric unit of2, the molecular structure of2is twisted with the dihedral angle between the two phenyl rings being 13.6(3)° in one molecule and 7.1(3)° in the other. In the crystal packing, the molecules of2are linked into chains along the b-axis by C‒H⋅⋅⋅O interactions. Antioxidant and antibacterial activities of1–5were also carried out. [ABSTRACT FROM PUBLISHER]

A series of N-ethyl phthalimide esters 4(a-n) were synthesized and characterized by spectroscopic studies. Further, the molecular structure of majority of compounds were analysed by single crystal X-ray diffraction studies. The X-ray analysis revealed the importance of substituents on the crystal stability and molecular packing. All the synthesized compounds were tested for in vitro antioxidant activity by DPPH radical scavenging, FRAP and CUPRAC methods. Few of them have shown good antioxidant activity. [ABSTRACT FROM AUTHOR]

A series of complexes of the type LAuCl where L = tris(p-tolylarsane), tris(m-tolylarsane), bis(diphenylarsano)ethane, and tris(naphthyl)arsane have been synthesized. All of the new complexes, 1-4, have been fully characterized by means of 1H NMR and 13C NMR spectroscopy and single crystal X-ray crystallography. The structures of complexes 1-4 have been determined from X-ray diffraction data. The linear molecules have an average bond distance between gold-arsenic and gold-chlorine of 2.3390Å and 2.2846Å, respectively. Aurophilic interaction was prominent in complex 1 and 3, whereas complex 2 and 4 do not show any such interaction. The intermolecular gold interaction bond length was affected by the electronegativity of the molecule. The computed values calculated at DFT level using B3LYP function are in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

A nickel-catalyzed and benzoic acid-promoted direct sulfenylation of unactivated arenes using removable 2-(pyridine-2-yl)-isopropylamine as a directing group is described. This strategy provides an efficient access to valuable aryl sulfides with ample substrate scope and a high degree of functional group tolerance. [ABSTRACT FROM AUTHOR]

Azodye–rhodamine hybrid colorimetric fluorescent probe (L) has been designed and synthesized. The structure of L has been established based on single crystal XRD. It has been shown to act as a selective turn-on fluorescent chemosensor for Pd2+ with ＞40 fold enhancement by exhibiting red emission among the other 27 cations studied in aqueous ethanol. The coordination features of the species of recognition have been computationally evaluated by DFT methods and found to have a distorted tetrahedral Pd2+ center in the binding core. The probe (L) has been shown to detect Pd up to 0.45 μM at pH 7.4. Furthermore, the probe can be used to image Pd2+ in living cells. [ABSTRACT FROM AUTHOR]

The title xanthone known as Formoxanthone C (1) was isolated from the green fruits ofCratoxylum formosumssp.pruniflorum. Compound1crystallized out inP21/c space group, indicating that1exists both enantiomers. The unit cell parameters area= 13.8038(2),b= 14.6712(2),c= 9.4686(1) Å,β= 95.358(1)°,V= 1909.19(4) Å3, andZ= 4. Theα,α,β-trimethyldihydrofuran ring was in an envelope conformation and disordered over two sites with 0.628(1) and 0.372(1) occupancies for the major and minor components, respectively, which corresponded to the less furan ring strain and the steric hindrance between the two methyl substituents (at positions 1′ and 2′) on the furan ring of the major component than that of the minor component. The crystal structure is stabilized by intermolecular O−H···O hydrogen bonds and weak C−H···O interactions. [ABSTRACT FROM AUTHOR]

Three derivatives of the novel (E)-2-cyano-N-(4-ethoxyphenyl)-3-methylthio-3-(substituted-amino)acrylamides3–5were selectively synthesized by the one-pot reaction of 2-cyano-N-(4-ethoxyphenyl)acetamide (2) with substituted isothiocyanates and methyl iodide in DMF containing potassium hydroxide as a basic catalyst. The stereochemistry and the structures of the synthesized compounds were confirmed by single crystal X-ray diffraction, IR,1H-NMR,13C-NMR, mass spectroscopy, and elemental analyses. [ABSTRACT FROM AUTHOR]

The monohydrazone of quinoxaline aldehyde (HOQA) is found to be a ratiometric and colorimetric probe for Ni2+. HOQA shows a remarkable color change from colorless to yellow upon specific and selective binding to nickel that can be identified even by the naked eye. The cation recognition property of the receptor is monitored by UV-vis and 1H-NMR titrations and also by DFT (Density Functional Theory) and TD-DFT (Time Dependent Density Functional Theory) calculations. [ABSTRACT FROM AUTHOR]

The direct decarboxylative arylation of hetereoarenes with benzoic acids through a nickel-catalyzed sp2 C-H functionalization process was developed. This process provides the first examples of decarboxylative cross-coupling reactions with aromatic acids through nickel catalysis and tolerates a variety of functional groups. Moreover, this method provides efficient access to 2-aryl-substituted azoles, an important structural unit in natural products, medicinal compounds, and functional materials. [ABSTRACT FROM AUTHOR]

Two new cadmium(II) and lead(II)-thiocyanato coordination polymers with 5,5′-dimethyl-2,2′-bipyridine (5,5′-dm-2,2′-bpy) as chelating ligands were synthesized and characterized by elemental analysis, IR and H NMR spectroscopy and by X-ray crystallography. Thermal and electrochemical properties were also studied as well. These complexes have formed formula [Cd(5,5′-dm-2,2′-bpy)(NCS)] ( 1) and [Pb(5,5′-dm-2,2′-bpy)(CHCOO)(NCS)] ( 2). The coordination numbers of Cd in 1 and Pb in 2 are six (CdNS) and seven (PbNOS), respectively. In 2, 'stereo-chemically active' electron lone pairs and the coordination spheres were hemidirected. Bridging properties of thiocyanato anions in 1 and 2 created one- and two-dimensional coordination polymers, respectively. The supramolecular features in these complexes were guided and controlled by weak directional intermolecular interactions. [ABSTRACT FROM AUTHOR]

C25H18ClFN4O3 · C2H6OS, monoclinic, P21 (No. 4), a = 6.0486(2) Å, b = 17.4704(7) Å, c = 11.9215(4) Å, β = 96.327(1)°, V = 1252.09(8) Å3, Z = 2, Rgt (F) = 0.0476, wRref (F2 ) = 0.1004, T = 100 K. [ABSTRACT FROM AUTHOR]

Glycosyltransferases (GTs), which are distributed widely in various organisms, including bacteria, fungi, plants and animals, play a role in synthesizing biological compounds. Glycosyltransferase-1 from Bacillus cereus ( BcGT-1), which is capable of transferring glucose to small molecules such as kaempferol and quercetin, has been identified as a member of the family 1 glycosyltransferases which utilize uridine diphosphate glucose (UDP-glucose) as the sugar donor. BcGT-1 (molecular mass 45.5 kDa) has been overexpressed, purified and crystallized using the hanging-drop vapour-diffusion method. According to X-ray diffraction of BcGT-1 crystals to 2.10 Å resolution, the crystal belonged to space group P1, with unit-cell parameters a = 54.56, b = 84.81, c = 100.12 Å, α = 78.36, β = 84.66, γ = 84.84°. Preliminary analysis indicates the presence of four BcGT-1 molecules in the asymmetric unit with a solvent content of 50.27%. [ABSTRACT FROM AUTHOR]

Clusters Ru3(CO)10(dppm) and Ru3(CO)10(dpam) on reaction with AsPh3 and PPh3 in refluxing n-hexane afford trisubstituted clusters Ru3(CO)9(dppm)AsPh3 and Ru3(CO)9(dpam)PPh3, respectively. These two trisubstituted clusters are characterized by spectroscopic and single-crystal X-ray diffraction. Ru3(CO)9(dppm)AsPh3 and Ru3(CO)9(dpam)PPh3 show a triangle of ruthenium atoms, in which the bidentate and monodentate group 15 ligands occupy equatorial position and all the carbonyl units are terminally bonded. The Ru-Ru distances in Ru3(CO)9(dppm)AsPh3 are 2.8461(7) Å, 2.8495(7) Å, and 2.8930(6) Å, with the longest distance cis to the monodentate AsPh3 ligand. For Ru3(CO)9(dpam)PPh3, the Ru-Ru distances are 2.8652(2) Å, 2.8809(2) Å, and 2.8560(2) Å with the longest distance also cis to the monodenatate PPh3 ligand. [ABSTRACT FROM AUTHOR]

Five new hydrazone derivatives, ( E)- N′-(4-fluorobenzylidene)-5-methyl-1-(4-nitrophenyl)-1 H-1,2,3-triazole-4-carbohydrazide, ( E)- N′-(4-chlorobenzylidene)-5-methyl-1-(4-nitrophenyl)-1 H-1,2,3-triazole-4-carbohydrazide, ( E)- N′-(4-bromobenzylidene)-5-methyl-1-(4-nitrophenyl)-1 H-1,2,3-triazole-4-carbohydrazide, ( E)- N′-(4-hydroxy-3-methoxybenzylidene)-5-methyl-1-(4-nitrophenyl)-1 H-1,2,3-triazole-4-carbohydrazide and ( E)- N′-(1-(4-bromophenyl)ethylidene)-5-methyl-1-(4-nitrophenyl)-1 H-1,2,3-triazole-4-carbohydrazide (denoted as A-E), were prepared and their molecular structures were characterized by single crystal X-ray diffraction. Compound A crystallizes in monoclinic P2/ c, a = 6.8057(1) Å, b = 12.7447(3) Å, c = 18.6936(3) Å, β = 105.356(1)°, B crystallizes in monoclinic P2/ c, a = 8.3815(2) Å, b = 20.8298(4) Å, c = 9.5932(2) Å, β = 99.612(1)°, C crystallizes in monoclinic P2/ c, a = 8.4213(8) Å, b = 21.077(2) Å, c = 9.5899(10) Å, β = 99.979(2)°, D crystallizes in monoclinic P2/ c, a = 11.1644(10) Å, b = 16.3508(15) Å, c = 9.7313(9) Å, β = 105.757(1)° and E crystallizes in triclinic $$P\bar{1}$$ , a = 8.7415(7) Å, b = 10.1032(8) Å, c = 11.6852(9) Å, α = 68.306(1)°, β = 84.894(1)°, γ = 68.289(1)°. All of the five compounds with close molecular conformations adopt a trans configuration with respect to the hydrazone C = N double bond and weak non-classical intermolecular C-H···O hydrogen bonds are observed in the crystal. Isomorphous substitution between compounds B and C with simple replacement of chlorine atom to bromine atom is giving rise to similar molecular geometries, unit cell parameters and intermolecular interaction pattern of three-dimensional network. Graphical Abstract: Five new hydrazone derivatives possessing 5-methyl-1-(4-nitrophenyl)-1,2,3-triazole moiety (denoted as A to E) are characterized by single crystal X-ray structure determination method. The intermolecular interaction pattern of D is strongly influenced by strong O-H···O hydrogen bond, whereas only non-classical C-H···O hydrogen bonds are observed in the rest. Compounds B and C with isomorphous chlorine-bromine substitution are crystallized under same space group and similar unit cell parameters.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Phenacyl benzoates possess commercial importance due to their various applications in the fields of synthetic and photochemistry, such as photosensitive blocking groups owing to their ease of cleavage under mild conditions. In the present study, a series of ten new 2-(4-bromophenyl)-2-oxoethyl benzoates 2( a-j), with the general formula Br(C6H4)COCH2OCO(C6H5- n X n), X = Cl, NO2 or NH2, and n = 1 or 2, have been synthesized by reacting 4-bromophenacyl bromide with various substituted benzoic acids using potassium carbonate in DMF medium at room temperature. These reactions proceeded with ease under mild conditions producing high purity products in good yield. Each product was characterized by mass spectra, elemental analysis and melting points, its 3D structure was confirmed by single-crystal X-ray diffraction studies. The X-ray 3D structures showed the flexibility of the C(=O)-O-C-C(=O) connecting bridge in which 7 out of 10 compounds tend to form a torsion angle in the range of 70 to 91°, whereas the rest are slightly twisted with a torsion angles of -160, 163, 176 and 178°. Their molecular conformations are in good agreement with another 22 related structures. These synthesized compounds were screened for their abilities for DPPH radical scavenging and ferric reducing anti-oxidant power. The results indicate that these compounds displayed mild anti-oxidant ability when compared to the standard anti-oxidant BHT. [ABSTRACT FROM AUTHOR]

A simple novel receptor, designed to have a combination of both oxygen and nitrogen-binding sites for metal ion and hydrogen bond donor sites for anion, was synthesised. The receptor has been explored for the selective detection of cation Al3+over the other interfering metal ions and anion AcO− against a range of physiologically relevant anions in the fluorescence spectroscopy. The receptor shows a different response to aluminium and acetate in the emission spectra. The binding isotherm and detection limit demonstrate that the receptor is an excellent fluorometric probe for Al3+and AcO− . Our receptorHNQrepresents a ‘Single sensor for multiple analytes’. A new array for the ‘naked-eye’ detection of cation (Al3+, blue colour) and anion (AcO− , green colour) in the emission spectra. The dual sensing to Al3+and AcO− is rare. [ABSTRACT FROM AUTHOR]

Two new derivatives of semicarbazone, ( E)-2-(hexan-2-ylidene)hydrazinecarboxamide and ( E)-2-(heptan-2-ylidene)hydrazinecarboxamide were synthesized and characterized by IR and H NMR. Their crystal structures were characterized by X-ray diffraction method. Compound ( I) crystallizes in triclinic $$P\overline{1}$$ , a = 6.7679(7) Å, b = 7.1912(8) Å, c = 9.9969(11) Å, α = 108.824(2)°, β = 99.398(3)°, γ = 92.680(2)°, V = 451.75(8) Å, Z = 2, R = 0.043 and wR = 0.140. Compound ( II) crystallizes in triclinic $$P\overline{1}$$ , a = 6.7192(6) Å, b = 7.2094(6) Å, c = 11.2842(11) Å, α = 103.303(2)°, β = 106.198(2)°, γ = 91.219(1)°, V = 508.70(8) Å, Z = 2, R = 0.044 and wR = 0.133. Their molecules adopt a L-shape conformation with C atom in C=N double bond acting as the junction point. The C=O double bond indicate the existence of semicarbazone group in keto-like form for both compounds in their solid state. In the crystal, the carbonyl O atom for both derivatives acts as a common acceptor in the intermolecular bifurcated N-H···O hydrogen bonding which linked the molecules into one-dimensional supramolecular ribbons. Antimicrobial studies by serial dilution method showed both compounds exhibit antibacterial property. Graphical Abstract: Two new semicarbazone derivatives are characterized by IR, H NMR and single crystal X-ray diffraction methods and their antibacterial activity was further investigated by screening against four different bacterial strains.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A new fluorescent probe was synthesized from rhodamine-6G and 6-(hydroxymethyl) picolinohydrazide for the sensing of Fe3+ in an aqueous environment. The structure of the sensor was confirmed through its single crystal X-ray study. It exhibits a high specificity and sensitivity towards Fe3+ over other interfering heavy and transition metal ions (HTM). The turn-on greenish-yellow fluorescence and a colorimetric change from colourless to pink were observed upon addition of Fe3+ which evokes almost 116- and 23-fold enhancement in absorbance and emission intensity respectively in an acetonitrile–water (1 : 1, v/v, 25 °C) solution at a neutral pH (pH = 7.2). The Fe3+ promoted ring opening of the spirolactam framework to the open chain amide platform of the sensor is responsible for its visible colour change and turn-on fluorescence activity. It also exhibits an excellent performance in the “dip stick” method. Moreover the limit of detection of the probe is in the 10−8 M range. [ABSTRACT FROM AUTHOR]

6-(4-Chlorophenyl)-4-(4-methoxyphenyl)-2-methoxynicotinonitrile ( 1) was synthesized by cyclization reaction of a chalcone derivative and malononitrile and characterized by FT-IR, UV-Vis, H NMR and single crystal X-ray diffraction. The crystal of 1 belongs to monoclinic unit cell in the P2/c space group with the unit cell dimensions a = 3.8596(5) Å, b = 27.460(3) Å, c = 15.3972(19) Å, β = 99.115(3), V = 1611.3(3) Å, Z = 4, D = 1.446 Mg m and F(000) = 720. In addition, the thermal gravimetric analysis and fluorescent property of 1 were also carried out. The results reveal that 1 shows high thermal stability up to 300 °C and emit the strong blue fluorescence at 437 nm when was excited at 332 nm. Graphical Abstract: 6-(4-Chlorophenyl)-4-(4-methoxyphenyl)-2-methoxynicotinonitrile ( 1) was synthesized and characterized by spectroscopy methods and single X-ray diffraction. Compound 1 possesses blue fluorescence at the maxima emission wavelength 437 nm (excited at 332 nm) and the TGA data reveals that 1 shows thermal stability up to 300ºC. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Butyrate derivatives of allyl 2-acetyl-3-(phenylamino)butanoate ( 1) and 1,3-dioxane derivatives of 2,6-dimethyl N-(4-methylphenyl)-1,3-dioxan-4-amine ( 2) and N-(3,5-diflourophenyl)-2,6-dimethyl-1,3-dioxan-4-amine ( 3) were synthesised. Their structures were characterized by FTIR ( 1) H NMR, C NMR spectroscopic techniques and single crystal X-ray diffraction. The compound ( 1) crystallizes in the triclinic crystal system with the space group p-1 with a = 10.0874(5) Å, b = 10.1751(5) Å, c = 14.1930(8) Å, α = 82.429(4)°, β = 77.482(4)°, γ = 80.820(4)°, v = 1396.77(13) Å. The compound ( 2) crystallizes in the monoclinic space group P2 with unit cell dimensions a = 9.8454(3) Å, b = 13.3032(4) Å, c = 10.1967(3) Å, α = 90°, β = 114.821(2)°, γ = 90°, v = 1212.15(6) Å. The compound ( 3) crystallizes in the triclinic space group p-1 with unit cell dimensions a = 9.65630(10) Å, b = 11.2266(2) Å, c = 11.2658(2) Å, α = 83.7710(10)°, β = 79.1770(10)°, γ = 77.1290(10)°, v = 1166.59(3) Å. Graphical Abstract: In the crystal packing of all the three crystal structures, the molecules are linked together by hydrogen bonds to form dimers. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A new rhodamine based chemosensor, cyano-rhodamine, has been designed and synthesized with a green approach which shows a specific ‘C–CN’ bond breaking with the action of the Pd2+ ion to produce the specific color and fluorescence of rhodamine 6G itself in solution and in HeLa cells. [ABSTRACT FROM AUTHOR]