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Two different heterocycles, thiazole-2-imines and imidazole-2-thiones, have been conveniently synthesized by just altering the sequential order (1 + 2 + 3 or 1 + 3 + 2) when combining the same components [aryl amine (1), aryl isothiocyanate (2), and phenacyl bromide (3)] in one-pot, three-component protocols. The third possible sequential order of combination (2 + 3 + 1) chemoselectively affords thiazole-2-imine. The finding is a stepping stone in the synthetic applicability of sequential one-pot, three-component protocols.

A new air-stable Pd(II) complex containing a sulfonamide–Schiff base ligand has been synthesized, characterized and investigated as a catalyst for the Suzuki–Miyaura reactions of aryl halides with arylboronic acids. Theoretical calculations (B3LYP) and spectroscopic evidence suggest that the sulfonamide–Schiff base coordinates to the Pd centre through sulfonamide nitrogen (SO2NH2) rather than imine (CHN). The complex shows excellent cross-coupling activity with aryl bromides in water at room temperature and aryl chlorides in isopropanol at 60°C. Copyright © 2016 John Wiley & Sons, Ltd.

Iminophosphoranes generated in situ from bis azides and trialkylphosphites or triphenylphosphine are applied in the esterification of various carboxylic acids under solvent-free conditions.

The first cross-coupling reaction between aryl/heteroaryl pentafluorobenzenesulfonates and aryl/heteroaryl boronic acids under mild conditions is described. The successful synthesis of highly ortho substituted biaryls and high chemoselectivity of these bench stable intermediates over tosylates, triflates, mesylates, and chlorides increases its scope as a valuable cross-coupling partner. The generality of this protocol was further extended to other boron containing nucleophiles (boronates, trifluoroborates) and alkyl boronic acids.

A mild, convenient, and efficient method for the synthesis of a wide range of the title compounds (III) from cost effective and easily available starting materials is developed.

Indazoles is an important class of heterocyclic compounds having a wide range of biological and pharmaceutical applications. There is enormous potential in the synthesis of novel heterocyclic systems to be used as building blocks for the next generation of pharmaceuticals as anti-bacterial, anti-depressant and anti-inflammatory. Fused aromatic 1H and 2H-indazoles are well recognized for anti-hypertensive and anti-cancer properties. The present review focuses on novel routes of their synthesis and various biological activities.

Azetidin-2-ones, commonly referred as β-lactams, represent a unique ring system, with interesting chemistry and great biological potential. Besides its well known antibiotic activity, this ring system exhibits a wide range of activities, attracting the attention of researchers. The biological and pharmacological profile of azetidin-2-ones is reviewed here comprehensively with several examples under fourteen different activity heads. The chemistry and methods of synthesis have also been discussed.

Silica-supported perchloric acid is found to be an efficient catalyst for the synthesis of 2-amino-1,4-naphthoquinones (III) (19 examples) via conjugate addition of primary and secondary amines to 1,4-naphthoquinone under ultrasonication.

A new method for the isolation of piperine (I) from Piper retrofractum Vahl by methanol/water is described.

A broad range of the functionalized title compounds is synthesized and evaluated for their inhibitory activity.

With a view to find novel sirtuin inhibitors, a series of substituted quinoxalines (V) (30 examples) is prepared by a hydroarylation—heteroarylation reaction.

The air-stable new complex renders possible the preparation of various biaryls in aqueous media.

A novel ligand-free palladium-catalyzed cascade reaction for the synthesis of highly diverse isoquinolin-1(2H)-one derivatives from isocyanide and amide precursors synthesized by Ugi-MCR has been developed. A broad variety of acids, amines, and isocyanides were used as starting materials for Ugi-MCR leading to various amide precursors, which in turn provided entry into diverse isoquinolin-1(2H)-one derivatives. The reaction proceeds through tandem isocyanide insertion with intramolecular cyclization followed by a Mazurciewitcz–Ganesan type sequence to provide isoquinoline-1(2H)-one derivatives in moderate to good yields.

Three-component condensation of dimedone with naphthol and aromatic aldehydes can be carried out either in aqueous media using sulfuric acid catalyst, or under microwave irradiation using solvent-less conditions.

Some of the title compounds, especially derivatives having two halogen-substituents, show better antimicrobial activity than the standard penicillin.

Dinitrile (I) is used as convenient starting compound for the preparation of derivatives (II), (IV), (VI), (VIII), and (X).

An in situ-generated catalytic system based on PdCl2 and primary amine-based ligand exhibited excellent activity (up to 98% isolated yield) in the Suzuki–Miyaura cross-coupling reactions of aryl bromides with arylboronic acids in water, at room temperature, without any additive. The efficiencies of the ligands follow the order: (C6H5)3CNH2 > C6H5CH2 NH2 > C6H5 NH2 > C6H11 NH2, which is in accordance with the palladacycle forming capacity of the respective ligands. Moderate-to-good yields (up to 78% isolated yield) of the coupling products were also obtained with less reactive aryl chlorides as substrates at room temperature in isopropanol using an alternative protocol based on Pd(OAc)2 and (C6H5)3CNH2. Copyright © 2011 John Wiley & Sons, Ltd.

1-Azaphenothiazine catalyses the intramolecular cyclization of N-(bromoalkyl)phthalimides in the presence of anhydrous K2CO3 to form spiro cyclic quaternary ammonium salts, namely azoniaspiro compounds, under microwave irradiation. A novel and ecofriendly method was developed for the synthesis of azoniaspiro compounds, and the role of azaphenothiazine as a catalyst in such reactions has been established for the first time. In the future, this protocol can be extended to the synthesis of various substituted N-heterocycles by hydrolyzing the resulting azoniaspiro compounds.

A simple, mild, and efficient method for the iodination of various aromatic amines, hydroxy aromatic aldehydes, hydroxy acetophenones and phenols is presented (34 examples).

Pyridylpyrimidine based potent and selective inhibitors of HIF-1α are designed and synthesized.

One flask synthesis of 4-arylmethylene-1-phenyl-2-styryl-2-imidazolin-5-ones was achieved by the phenyl isothiocyanate-mediated condensation of N-acetyl glycine with aromatic aldehydes.

A variety of substrates is regioselectively iodinated under mild conditions in short reaction times.

Electrochemical selenization of vacuum-deposited metal films in (SeSO 3 ) 2- containing baths have been described for the preparation of metal selenide semiconductor thin films. Energy dispersive x-ray analysis and x-ray diffraction studies show that CuSe, InSe, and CdSe thin films prepared by this technique are adherent, single phase, and spatially homogeneous. The stoichiometry and crystallographic phase of the semiconductor films depends on the kinetics of selenization but are less critically dependent on selenization current and Se concentration under parameters favoring uninhibited selenization

A one pot synthesis of 5,6- and 5,7-dichloro-3-methyl-4H,4-benzothiazines is reported by the condensation and oxidative cyclization of 2-amino-3,4- and 3,5-dichlorobenzenethiols with β-dicarbonyl compounds. The oxidation of 4H-1,4-benzothiazines by 30% hydrogen peroxide in glacial acetic acid has provided the corresponding sulfones. The effect of the conversion of the sulfide linkage to sulfone is discussed. The structure of all the newly synthesized compounds has been confirmed by elemental analysis and spectral studies.

Treatment of p-toluenesulfonates of epoxides of specific primary allylic alcohols with telluride ion, prepared in situ by reduction of relatively nontoxic elemental tellurium, installs the two key secondary alcohol functions that occur in the lactone part of the cholesterol-lowering drugs, compactin, mevinolin, and lovastatin. Since the epoxides of the primary allylic alcohol starting materials can be synthesized in optically active form by the Sharpless-Katsuki asymmetric epoxidation (SAE) process, the stereospecific telluride transposition can give optically active secondary allylic alcohols configured for maximum inhibition of cholesterol formation

A convenient procedure for the mononitration of carbazole and 9-alkylcarbazoles using CAN in CH3CN in presence of SiO2 is reported. The results with 9-acetyl, 9-benzoyl and 9-benzenesulphonylcarbazoles are also discussed.

The syntheses of fluorinated phenothiazines and fluorinated 1,4-benzothiazines are reported.Fluorinated phenothiazines have been prepared via a Smiles rearrangement of N-formylateddiphenylsulphides, synthesized in turn by condensation of substituted 2-aminobenzenethiolswith 2-chloro-5-trifluoromethylnitrobenzene followed by formylation with formic acid.Fluorinated 4H-1,4-benzothiazines have been prepared by the condensation and oxidativecyclization of substituted 2-aminobenzenethiols with p-fluorobenzoylacetone in DMSO.The reaction is believed to proceed via an enaminoketone system. IR and NMR spectralinvestigations are included.

A new and efficient synthesis has been developed for the title indolocarbazole which has been indicated by a recent computer-aided study to be a potent ligand for the receptor for the naturally occurring carcinogen, TCDD.

Knoevenagel products 3 of 3-formylchromone (1) with isoxazol- 5-one 2, after reduction with NaBH4 and exposure to aqueous sodium nitrite/acetic acid and ferrous sulphate gave various benzopyranacetylenes 4 in good yield. IICT Communication No. 3850

Reaction of ethyl 4-bromomethylbenzoate with the carbanion of substituted ethyl acetate affords nucleophilic aromatic substitution of the bromomethyl group instead of the expected alkylation of the benzylic bromide.

A simple catalytic system based on PdCl 2 and triphenylphosphine chalcogenides (PPh 3 X; X = O, S, Se) is found to be highly effective (up to 97% isolated yield) in the room temperature Suzuki–Miyaura reactions. Under the same experimental conditions, triphenylphosphine chalcogenides as ligands show superior activities compared to free triphenylphosphine.