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The present work reports a simple, mild and efficient protocol for the reduction of xanthenediones to 8-hydroxy xanthenones and xanthene1,8-diols by using readily available, cost efficient, easy to handle sodium borohydride as the reducing agent. The products obtained are in good to excellent yields with a short reaction duration. The versatility of the reaction, mild reaction conditions, in combination of high yields and easy work-up makes this reaction noteworthy. The synthesized compounds were analyzed spectroscopically. Further, four derivatives were recrystallized and structures were confirmed by crystallographic studies. The crystal structures are stabilized by intermolecular O–H···O hydrogen bonds and C–H···O weak interactions. [ABSTRACT FROM AUTHOR]

The present work deals with a practically efficient protocol designed for the synthesis of 2,7-dibromoxanthenediones using N-bromosuccinimide (NBS) in the presence of p-toluene sulfonic acid (PTSA). A combination of NBS and PTSA in chloroform is an efficient system for selective α-bromination of xanthenediones under mild reaction conditions. The main advantage of this method is short reaction duration, mild reaction conditions, easy work up and in addition the method provides excellent yields. All the compounds synthesized were characterized by spectroscopic techniques. [ABSTRACT FROM AUTHOR]

The title compounds were synthesised by the reaction of substituted benzaldehyde with dimedone in presence of liquid ammonia in a water–ethanol system. The yields of the synthesised products were 93 and 87%, respectively. Single crystals were obtained after chromatographic purification technique at the same temperature and under the same solvent conditions. The compounds 3a and 3b crystallize in orthorhombic and monoclinic crystal system in Iba2 and P21/c space groups. The aryl rings of both compounds 3a and 3b are oriented orthogonal to the plane of the pyridine ring with dihedral angles of 86.61° and 87.28°, respectively. The central pyridine ring of compounds 3a and 3b takes the shape of a boat and planar conformation, respectively. Crystal structures are stabilized by N–H⋅⋅⋅O, C–H⋅⋅⋅O and C–H⋅⋅⋅F intermolecular interactions. Compound 3a is stabilized by hydrogen bonds, whereas compound 3b is stabilized only by weak intermolecular interactions. [ABSTRACT FROM AUTHOR]

A rapid and green approach for the synthesis of xanthenediones. This approach has many advantages such as environmentally friendly procedure, excellent yields, and short duration. The products were further confirmed by X-ray crystallography. The compounds 3a and 3b crystallize in space group P21/c and Pbca. The structures are stabilized by C–H···O and O–HˑˑˑO hydrogen bonds. Further, DFT and Hirshfeld surface analysis was carried out to visualize and explore several short intermolecular interactions on the molecular surface. The 2-D fingerprint plot provided the percentage contribution of each individual interactions with 61.9%, 64.0% overall contacts for the compounds 3a and 3b, respectively. [ABSTRACT FROM AUTHOR]

The present work describes the synthesis of 4-amino-6-(2-benzylidenehydrazinyl)-pyrimidine-5-carbonitrile derivatives, 4-amino-6-[(2-phenylethyl)amino]pyrimidine-5-carbonitrile, and 4-amino-6-(piperidin-1-yl)pyrimidine-5-carbonitrile. The compounds were characterized by FT-IR and 1H and 13C NMR spectroscopy and mass spectrometry. All the compounds were evaluated for in vitro antimicrobial activity against different bacterial and fungal strains. The minimum inhibitory concentrations (MICs) of all the compounds were validated. 4-Amino-6-[2-(3,4-dimethoxybenzylidene)hydrazinyl]pyrimidine-5-carbonitrile and 4-amino-6-(piperidin-1-yl)pyrimidine-5-carbonitrile, which have the lowest MIC values were selected for cell leakage analysis and bacterial growth curve study. It was found that both the compounds have potential to induce bacterial cell membrane rupture and disintegration. Field emission scanning electron microscopic analysis confirmed the effect of the selected compounds on the morphology of both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. The mechanism of interaction between the drug and the target protein of S. aureus and E. coli was studied by molecular docking. [ABSTRACT FROM AUTHOR]

A novel and efficient Mn(III)-mediated oxidative radical cascade reaction of 1-(azidomethyl)-2-isocyanoarenes with organoboronic acids is reported. The single electron oxidation of a commercially available organo boronic acid in the presence of a mild oxidant, Mn(OAc)3·2H2O, resulted in moderate yields of the corresponding quinazoline derivatives. [ABSTRACT FROM AUTHOR]

This study reports the synthesis of new indol(1H-3-yl) pyrimidine derivatives 4(a-e) using various substituted indole-3-carbaldehydes, urea and malononitrile in the presence of ammonium chloride. The resulting compounds were characterized using analytical and spectroscopic methods. The molecular docking study exhibits that among the synthesized compounds, 4(c-e) have great binding ability toward B-DNA. The binding efficiencies of compounds 4(c-e) with CT-DNA were evaluated via UV-visible absorption spectral and viscosity studies. The findings establish that the compounds firmly bind through an intercalative mode to CT-DNA and provide a unique pattern of DNA binding. The photo-induced cleavage indicates that the compounds have UV-visible photo nuclease properties toward plasmid DNA as revealed by agarose gel electrophoresis approach. [ABSTRACT FROM AUTHOR]

The present work deals with a practically efficient protocol designed for the synthesis of tetraketones using ultrasound in the presence of boric acid as the catalyst. One of the tetraketone, (3a) was confirmed by crystallographic studies. The molecules in crystal lattice are held together by weak intermolecular C–H···O, C–H···π and intramolecular O–H···O interactions. Hirshfeld surface analysis was carried out for the graphical visualization, while, the 2D fingerprint plots provide percentage contribution of each individual atom-to-atom interactions. Finally, to determine molecular electrical transport properties, we studied the energy difference between highest occupied, HOMO, and lowest unoccupied, LUMO orbitals. [ABSTRACT FROM AUTHOR]

With alkyl carbazates as the green ester source, a novel palladium‐catalyzed oxidative free radical carbonylative transformation of the C–H bond on aromatic rings to produce esters has been developed. Good yields of the corresponding products have been obtained with wide functional group tolerance and excellent regioselectivity. A variety of alkyl carbazates are found to be suitable reactants for the ortho‐alkoxycarbonylation on the aromatic ring. [ABSTRACT FROM AUTHOR]

Mn-TBHP mediated oxidative radical cyclization of 2-(azidomethyl)phenyl isocyanides using methyl carbazate has been described. This procedure is realized through a cascade radical addition and aromatization process with high atom economy to furnish various heterocyclic C2 diversified quinazoline-2-carboxylate derivatives. [ABSTRACT FROM AUTHOR]

A one-pot synthesis of some novel anionic scaffolds: the substituted-4-((4-trimethylsilyl-1H-1,2,3-triazol-1-yl)methyl)-2H-chromen-2-one is reported. Reaction of 10 different substituted bromomethylcoumarins with trimethylsilylacetylene and sodium azide in the presence of copper(I) iodide catalyst gave the corresponding heteroaryl conjugates: the substituted-4-((4-trimethylsilyl-1H-1,2,3-triazol-1-yl)methyl)-2H-chromen-2-one in 70–92% yields. The structures of the synthesized compounds have been completely characterized by spectral and elemental analyses. For the first time, the representative single-crystal X-ray structure analysis of 6-methoxy-4-((4-trimethylsilyl-1H-1,2,3-triazol-1-yl)methyl)-2H-chromen-2-one is reported which confirms the formation of anionic synthon which bears the trimethylsilyl-group. [ABSTRACT FROM AUTHOR]

The TiO2 thin films doped by Ni uniformly and non-uniformly were prepared on glass substrate from an aqueous solution of ammonium hexa-fluoro titanate and NiF2 by liquid phase deposition technique. The addition of boric acid as an F- scavenger will shift the equilibrium to one side and thereby deposition of the film is progressed. The rate of the reaction and the nature of deposition depend on growing time and temperature. The resultant films were characterized by XRD, EDAX, UV and SEM. The result shows that the deposited films have amorphous background, which becomes crystalline at 500°C. The EDAX data confirms the existence of Ni atoms in TiO2 matrix. XRD analysis reveals the peaks corresponding to Ni but no peak of crystalline NiO was found. The transmittance spectra of Ni uniformly and non-uniformly doped TiO2 thin films show 'blue shift and red shift', respectively. Ni-doped TiO2 thin films can be used as photocatalyst for the photodegradation of methyl orange dye. It was found that, organic dye undergoes degradation efficiently in presence of non-uniformly Ni-doped TiO2 thin films when compared to uniformly doped films and pure TiO2 films under visible light. The photocatalytic activity increases with increase in the concentration of Ni in case of nonuniformly doped thin films but decreases with the concentration when uniformly doped thin films were used. [ABSTRACT FROM AUTHOR]

Boron doped TiO2 thin films have been successfully deposited on glass substrate and silicon wafer at 30°C from an aqueous solution of ammonium hexa-fluoro titanate and boron trifluoride by liquid phase deposition technique. The boric acid was used as an F- scavenger. The resultant films were characterized by XRD, EDAX, UV and microstructures by SEM. The result shows the deposited film to be amorphous which becomes crystalline between 400 and 500°C. The EDAX and XRD data confirm the existence of boron atom in TiO2 matrix and a small peak corresponding to rutile phase was also found. Boron doped TiO2 thin films can be used as photocatalyst for the photodegradation of chlorobenzene which is a great environmental hazard. It was found that chlorobenzene undergoes degradation efficiently in presence of boron doped TiO2 thin films by exposing its aqueous solution to visible light. The photocatalytic activity increases with increase in the concentration of boron. [ABSTRACT FROM AUTHOR]

A transparent, high purity titanium dioxide thin film composed of densely packed nanometer sized grains has been successfully deposited on a glass substrate at 30°C from an aqueous solution of TiO2-HF with the addition of boric acid as a scavenger by liquid phase deposition technique. From X-ray diffraction measurement, the deposited film was found to be amorphous and turns crystalline at 500°C. The deposited film showed excellent adherence to the substrate and was characterized by homogeneous flat surface. TiO2 thin films can be used as a photocatalyst to clean up organohalides, a class of compound in pesticides that pollute the ground water. Photocatalytic degradation experiments show that indanthrene golden orange dye undergoes degradation efficiently in presence of TiO2 thin films by exposing its aqueous solution to ultraviolet light. The suitable surface structure and porosity increases the photocatalytic activity. It was also observed that hemin doped TiO2 thin films break up organohalides at a surprisingly high rate under visible light. [ABSTRACT FROM AUTHOR]

Cr–P alloys being new materials of great importance in futuristic activities of metal finishing industries, are developed by electroless plating from a bath solution containing reducing agent NaH2PO2, Cr3+ ions and KCNS as a complexing agent under acidic condition. Electronic absorption spectra of bath solution indicated the formation of a metal-complex of octahedral geometry. Microstructure, surface morphology and corrosion resistance of the coated alloys depend on bath components, bath composition and alloy composition and heat treatment of the coating. [Copyright &y& Elsevier]

• Ultrasound promoted one pot synthesis of Xanthenediones. • The reactions were carried out by the using boric acid as the catalyst in green solvent medium such as ethanol- water in an efficient manner. • Excellent yields were achieved in short reaction duration. • Two of the products obtained were confirmed by Single crystal X-ray analysis. • DFT calculations have been employed for optimization of these molecules at B3LYP hybrid functional in conjugation with 6-31G (d,p) level of basis sets. • Frontier molecular orbital analysis has been carried out to gain insights into role of different groups towards the HOMO and LUMO of the molecule. • The Mulliken atomic charges and MEP were analyzed for the nucleophilic and electrophilic regions of the molecular surface. A highly versatile and efficient ultrasound promoted synthesis of xanthenedione derivatives is achieved through condensation of dimedone with various aromatic aldehydes using boric acid as catalyst in ethanol-water medium. The advantages of this method being, mild reaction conditions, short reaction time, easy work-up, purification of products by non-chromatographic methods and additionally this method provides excellent yields. Two of the Xanthendiones derivatives 3a and 3b gave good crystals on recrystallization and their molecular structures were confirmed by crystallographic studies. The molecules in the crystal lattice are held together by weak intermolecular C-H•••O and C-H•••N interactions. Further insights into these interactions using Hirshfeld surface analysis and DFT/B3LYP studies show that in compound 3a H•••H (54.7%), O•••H (18.3%) and in 3b H•••H (53.7%), O•••H (17.6%) are the major contributors to the intermolecular interactions which stabilize the crystal structures. In order to determine molecular electrical transport properties, we studied the energy difference between Highest Occupied, HOMO, and Lowest Unoccupied, LUMO orbitals and the HOMO and LUMO energy gap for compounds 3a and 3b was found to be 3.9261 eV and 4.6436 eV respectively. The 2D fingerprint plot provided percentage contribution of each individual atom-to-atom interactions. The Mulliken atomic charges and molecular electrostatic potential on molecular van der Waals surface were calculated to know the electrophilic and nucleophilic regions of the molecular surface. [ABSTRACT FROM AUTHOR]

2-Aminothiazoles have been synthesized by a one-pot, two-step sequential procedure in solution state which does not involve the isolation of intermediates. It involves α-halogenation of corresponding precursor ketones followed by condensation with substituted thiourea derivatives. All the products were analyzed by IR, NMR, mass spectral techniques and four of them were evaluated crystallographically. One of them crystallizes in the triclinic crystal system with space group P 1 ¯ , while, all the other compounds crystallize in the monoclinic crystal system in two different space groups viz. P21/c and P21/n. The modified 2-aminothiazole core did not show any change in the intermolecular interaction. The N-H...N interaction predominates over other interactions forming centrosymmetric head to head dimer with the neighboring atoms. This feature is observed in all the molecules except N-(4-(4-bromophenyl)-3-(2,5-dimethylphenyl)thiazol-2(3H)-ylidene)-2,5-dimethylaniline. [ABSTRACT FROM AUTHOR]

In the title compound, C14H15N3O4S, the tetra­hydro­pyrimidine ring adopts a half-boat form. There are inter­molecular N—H⋯O hydrogen bonds and π–π stacking inter­actions. [ABSTRACT FROM AUTHOR]

The title compound, C12H22ClNO, adopts the square conform­ation [3333] observed in other known saturated twelve-membered rings. Disorder is observed, resulting from exchange of the chloro and nitroso substituents. [ABSTRACT FROM AUTHOR]

The title compound, C21H24O6, is the reduced form of curcumin, and exhibits important cosmoceutical properties. The molecule is non-planar and the benzene rings positioned at the ends of the heptane chain are orthogonally placed, with a dihedral angle of 84.09 (7)° between them. The molecular geometry and H-atom locations reveal that the 'heptane-3,5dione' moiety exists in the keto-enol form, with the hydroxy H atom disordered over two adjacent sites. The packing of the molecules in the lattice is directed by strong O-H···O intermolecular hydrogen bonds, which generate two-dimensional sheets. These sheets are linked by C-H···O hydrogen bonds and weak C-H···π interactions to develop a threedimensional network. [ABSTRACT FROM AUTHOR]

Thiazolo[3,2-a]pyrimidines namely ethyl 2-acetyl-5-(2-fluorophenyl)-3,7-dimethyl-5H-thiazolo[3,2-a]pyrimidine-6-carboxylate 3a, ethyl 2-acetyl-5-(3-fluorophenyl)-3,7-dimethyl-5H-thiazolo[3,2-a]pyrimidine-6-carboxylate 3b, and ethyl 2-acetyl-5-(4-fluorophenyl)-3,7-dimethyl-5H-thiazolo[3,2-a]pyrimidine-6-carboxylate 3c were obtained by one pot synthesis using substituted 3,4 dihydropyrimidine2-thione (1a–1c) and 3-chloro-2,4-pentanedione in ethanol and characterized by single-crystal X-ray diffraction. The variation in the position of fluorine atom on pyrimidine nucleus and insight into the self-assembly of compounds with varied types of non-covalent interactions has great influence on crystal packing. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, C17H20N2O5, is stabilized by C—H...O and N—H...O hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title compound, C22H16N2S2, the benzothiazole and tolyl ring systems are inclined at an angle of 31.23 (8)°, and the dihedral angle between the phenyl and benzothiazole rings is 7.567 (2)°. In the crystal structure, intermolecular C—H...N hydrogen bonds link the molecules into a two-dimensional sheet and π–π stacking interactions [perpendicular distance 3.6170 (4) Å] reinforce the crystal cohesion. [ABSTRACT FROM AUTHOR]

In the title compound, C14H13N3O2S, the imidazothia­diazole ring system and the methoxy­phenyl ring are not coplanar, having an angle of 31.60 (7)° between their mean planes. In the crystal structure, inter­molecular C—H⋯O hydrogen-bond inter­actions link the mol­ecules into dimers and π–π stacking inter­actions reinforce the crystal cohesion. [ABSTRACT FROM AUTHOR]

The sequential synthesis of eleven novel 1-trimethysilyl-2-arylcyclohexenes 4a – k from 1-bromo-2-chlorocyclohexene ( 1 ) is reported. The Suzuki cross coupling of 1 with eleven aryl boronic acids 2a – k gave the 1-chloro-2-arylcyclohexenes 3a – k in >90% yields. Wurtz–Fittig coupling reaction of 3a – k with metallic sodium and chlorotrimethylsilane in anhydrous ether solvent afforded the novel anionic synthons: 1-trimethylsilyl-2-arylcyclohexenes 4a – k in 65–87% yields. The cyclic vinylsilanes 4a – j are liquids, and 1-trimethylsilyl-2-biphenylcyclohexene ( 4k ) exists as a solid. The crystal structure of 4k is discussed. A plausible mechanism for the Wurtz–Fittig reaction and formation of vinylsilanes is highlighted. [ABSTRACT FROM AUTHOR]

An abstract of the study "Synthesis of 1-Trimethylsilyl-2-arylcyclohexenes: A New Class of Anionic Synthons" by M. S. Krishnamurthy and colleagues is presented.

The synthesis of a variety of new derivatives of thiazolopyrimidine including tricyclic compound (XX) and some arylidene derivatives (III) is described. [ABSTRACT FROM AUTHOR]

The reaction of 3,4-dihydropyrimidine-2-thiones (I) with α-haloesters (II)/(IV) leads to corresponding substituted diesters of thiazolopyrimidine (III) or (V), respectively. [ABSTRACT FROM AUTHOR]

X-ray characterization of 7-methyl-5,6,7,8- tetrahydro[1]benzothieno [2,3-d]pyrimidin-4[3H]one is described. The compound crystallizes in the monoclinic space group P21/c with a=7.0013(2)Å, b=8.3116(3)Å, c=18.374(6)Å, β=91.746(2)°, V=1068.76(6)Å3, z=4. The structure was solved using the direct method and refined to reliability R-factor of 0.0639 using 3180 independent reflections The crystal structure is further stabilized by intermolecular C-H…N, N-H…N C-H…O, N-H…O, and π-π interactions. [ABSTRACT FROM AUTHOR]

Preparation of 2-(4-fluorobexzyl)-6-(4-nitrophenyl)imidazo[2,1-b][1,3,4]thiadiazole is described and its crystal structure is discussed. The compound crystallizes in the monoclinic space group C2/c with a = 39.941(6) Å, b = 5.698(2) Å, c = 13.272(5) Å β = 90.880°, V = 3020(2) Å3, z = 8. The crystal structure is stabilized by weak intermolecular C-H...N,C-H...O,C-H...S, and C-H...F interactions. [ABSTRACT FROM AUTHOR]

The crystal and molecular structure of 2-(4-fluoro-benzyl)-6-phenyl-imidazo[2,1-b][1,3,4]thiadiazole-5-carbaldehyde is described. The compound crystallizes in the monoclinic space group P21/n with a = 7.419(3)Å, b = 8.287(3)Å, c = 25.734(10)Å, β = 91.686(8)°, V = 1,581.6(10)Å3, z = 4. The crystal structure is stabilized by intermolecular C-H...N, C-H...O, and C-H...F interactions. [ABSTRACT FROM AUTHOR]

Abstract: Electrodeposition of Fe–W alloy has been carried out from acidic triammonium citrate (TAC) complex bath solution. The deposit is characterised by XRD, SEM, EDAX, XPS and polarization techniques. The alloys are amorphous and become partially crystalline on heat treatment. The composition (Fe/W) of elements in the coating and their oxidation states vary from the surface to the bulk of the material. The coatings exhibit as novel electrode material with low over voltage and good corrosion resistance for anodic oxidation of methanol in H2SO4 medium. The anodic peak current, a measure of oxidation reaction rate is considerably high on Fe–W alloy when compared to pure Fe and also the relative surface area of Fe by alloying it with W found to increase by 1200-fold. [Copyright &y& Elsevier]

Structures of the compounds 1-dimethyl amino-3-dimethyl imino 2-(para chlorophenyl) prop-1-ene perchlorate, C 13 H 20 N 2 O 4 Cl 2 ( 3 ) 1-dimethyl amino-3-dimethyl imino 2-(para nitrophenyl) prop-1-ene perchlorate, C 13 H 20 N 3 O 6 Cl( 6 ), and 1-dimethyl amino-3-dimethyl imino 2-(phenyl) prop-1-ene perchlorate, C 13 H 21 N 2 O 4 Cl( 7 ) have been solved. The compounds exhibit NLO property. The C-N bonds are of the order of 1.32 Å, showing a pseudo double bond character. [ABSTRACT FROM PUBLISHER]

Structures of the compounds 1-dimethyl amino-3-dimethyl imino 2-(para chlorophenyl) prop-1-ene perchlorate, C 13 H 20 N 2 O 4 Cl 2 ( 3 ) 1-dimethyl amino-3-dimethyl imino 2-(para nitrophenyl) prop-1-ene perchlorate, C 13 H 20 N 3 O 6 Cl( 6 ), and 1-dimethyl amino-3-dimethyl imino 2-(phenyl) prop-1-ene perchlorate, C 13 H 21 N 2 O 4 Cl( 7 ) have been solved. The compounds exhibit NLO property. The C-N bonds are of the order of 1.32 Å, showing a pseudo double bond character. [ABSTRACT FROM AUTHOR]

The article presents chemical structure for the ultrasonic synthesis and crystal structure analysis of two Trimethylsilyloxy-substituted Bicyclo[2.2.2]octene derivatives, which was published in a 2013 issue of the periodical "Journal of Chemical Sciences."

In the title compound, C14H10O4S2·0.5CH3OH, the molecule adopts a gauche conformation around the central C—C bond. Intermolecular O—H...O hydrogen bonds between carboxyl groups link the molecules into zigzag chains. Between chains, the thiophene rings form π–π stacking interactions with a centroid–centroid distance of 3.98 Å. The methanol solvent molecule forms an O—H...O hydrogen bond to one carboxyl group and is disordered about a crystallographic centre of inversion. [ABSTRACT FROM AUTHOR]