Tantalum(V) Chloride–Silica Gel: An Efficient Catalyst for Conversion of Carbonyl Compounds to 1,3‐Oxathiolanes

A variety of carbonyl compounds can be easily converted to the corresponding 1,3‐oxathiolanes in the presence of a catalytic amount of tantalum(V) chloride [TaCl₅] on silica gel in dichloromethane. Mild reaction conditions, efficiency, high yields, operational simplicity, and only 2.5 mol% of TaCl₅ catalyst are some of the major advantages of the procedure.     

Chlorination of Quinonoid Compounds Using Dichlorine Monoxide

Dichlorine monoxide is a selective reagent for the monochlorination at the active quinonoid position in benzoquinones and naphthoquinones.     

One‐Pot Synthesis of Oxime Derivatives of 1,3‐Diphenylpyrazole‐4‐carboxaldehydes from Acetophenone Phenylhydrazones Using Vilsmeier–Haack Reagent

A one‐pot synthesis of oxime derivatives 3a–3f of 1‐phenyl‐3‐arylpyrazole‐4‐carboxaldehydes has been accomplished by the Vilsmeier–Haack reaction of acetophenone phenylhydrazones 1a–1f under a new workup procedure.     

A Convenient Synthesis of 3-Behzyl, 3-Benzyl-4-Substituted Coumarins and Their Benzo Derivatives

It is reported in the literature that alkylation of simple (unsubstituted) phosphorane with alkyl halide in ethyl acetate leads to equimolar mixture of alkylated phosphorane and salt of the unsubstituted phosphorane. Here we report exclusive formation of alkylated phosphorane from its salt from benzyl bromide in chloroform. This alkylated phosphorane (2) on reaction with 2-hydroxy carbony1 compounds (1a-1) provide E-ethyl Oc-benzyl cinnamates in high yields which on thermal cyclisation gave 3-benzylf 3-benzyl-4-substituted and benzocoumarins. Thus this method can be used conveniently to synthesise above compounds in good yields.     

First Example of Te-C Bond Cleaved Product in the Reaction of C8 H 8 TeI 2 with Ammonium Pipertidine Dithiocarbamate

Abstract

A series of 1,3-dihydro-2λ⁴-benzotellurole-2,2-diyl di-thiocarbamates C₈H₈TeR₂ and C₈H₈TeIR ( R═ S ₂CNC₅H₁₀, S₂CNHC₆H₅, S₂CNC₄H₈O) have been synthesised by the reactions of C8H8TeI₂ with the corresponding ammonium salts of piperidine-, aniline- and morpholine- dithiocarbamates in 1:1 and 1:2 molar ratio, respectively. They have been characterized by FT-IR and (¹H, ¹³C) NMR spectroscopy. The reaction of C₈H₈TeI₂ with (NH₄S₂CNC₅H₁₀) in 1:2 molar ratio gives C₈H₈Te(S₂CNC₅H₁₀)₂ [IR, (¹H, ¹³C)NMR evidence] and X-ray quality crystals of Te(S₂CNC₅H₁₀)₂ in very low yield, demonstrating the formation of the first Te–C bond-cleaved product.The monomers of Te(S₂CNC₅H₁₀)₂ are connected through intermolecular Te…S secondary bonds and it exists as a dimer in the solid state. These dimers are interconnected through intermolecular S…S secondary bonds to yield 3D-supramolecular network.     

Synthesis and Antimicrobial Evaluation of Halogen-Containing Arylidene Thiazolo Triazinediones

A series of 7-substituted arylidene-1,3-thiazolo[2,3-c]-1,2,4-triazine-4,6-diones were synthesized in an one-pot multicomponent reaction of 6-arylmethyl-3-mercapto-1,2,4-triazin-5-ones with substituted benzaldehydes and monochloroacetic acid in the presence of acetic anhydride, acetic acid, and sodium acetate. The structures of the new compounds were supported by IR, ¹H NMR, MS, and analytical data. All the new compounds were tested for their antibacterial and antifungal activity. Arylidene thiazolo triazinediones with 1,3-benzodioxolo substituent at seventh and p-chlorophenyl or 2,4-dichlorophenyl substituents at third displayed good antibacterial and antifungal activity. And also compound bearing 2,3,5-trimethoxyphenyl substituent at seventh and 2,4-dichlorophenyl substituent at third displayed good activity.     

Thermal studies of some biological active oxadiazoles

A series of new unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles (3a–d) has been synthesized to evaluate their antibacterial and thermal properties. All compounds have been tested for their in vitro antibacterial activity against two Gram-positive bacteria namely, Staphylococcus aureus and Bacillus subtilis. Among the tested compounds, compound 2-(4-chlorophenyl)-5-(thiophen-2-yl)-1,3,4-oxadiazole (3c) has been found to be most potent member having minimum inhibitory concentration. Thermal stability and melting point of compounds have been studied by TG and DSC analysis in air atmosphere at heating rate of 10 °C min^?1. Thermal degradation kinetics of the most potent antibacterial compound 3c has been carried out by multiple heating rate model free kinetic methods namely, Ozawa–Flynn–Wall, modified Coats-Redfern, and Kissinger.     

Novel N-substituted-5-phenyl-1H-pyrazole-4-ethyl carboxylates as potential NLO materials

In the present investigation we have synthesized a novel series of N-substituted-5-phenyl-1H-pyrazole-4-ethyl carboxylates, which are characterized by ¹H NMR, UV–Vis and FT-IR spectroscopy methods. The optical nonlinearity of the compounds in chloroform solution has been studied at 532 nm using 5 ns laser pulses, employing the open-aperture z-scan technique. It is found that compound 3c having carboxylic acid group and ester substituent has maximum nonlinearity. From measurements we conclude that compounds 3c (4-[4-(ethoxycarbonyl)-5-phenyl-1H-pyrazol-1-yl]benzoic acid) and 3e (ethyl 1-(2-bromophenyl)-5-phenyl-1H-pyrazole-4-carboxylate) are potential candidates for optical limiting applications.     

Inhibitory potential of Hydroxychavicol on Ehrlich ascites carcinoma model and in silico interaction on cancer targets

Abstract

Hydroxychavicol (HC), a major phenolic derivative isolated from the leaves of Piper betle L. is well known for its antibacterial, antifungal and antimutagenic properties. The present study evaluated the in vivo antitumor activity of HC against Ehrlich Ascites Carcinoma (EAC) cells in Swiss albino mice and in silico interaction of HC with the receptors involved in the cancer. Hydroxychavicol (200 and 400?mg/kg bw) was orally administered for 21 consecutive days and was effective in inhibiting the tumor growth in ascitic mouse model. HC consistently reduced the tumor volume, viable cell count, lipid peroxidation and elevated the life span of HC treated mice. Besides the hematological profiles, SGOT and SGPT levels reverted back to normal and oxidative stress markers GSH, SOD and CAT also increased in HC treated groups. In silico docking analysis revealed that HC possessed potent antagonist activity against all the cancer targets demonstrating its inhibitory activity.     

Pulsed laser–deposited Li2TiO3 thin film electrodes for energy storage

Journal of Solid State Electrochemistry - Li2TiO3 (LTO) is a promising Ti-based material showing interesting electrochemical performance, good structural stability, cost-effectiveness, and...