Access to highly substituted oxazoles by the reaction of α-azidochalcone with potassium thiocyanate.

The reactivity of α-azidochalcones has been explored for the preparation of highly substituted oxazoles via a 2-azirine intermediate. The azidochalcones, when treated with potassium thiocyanate in the presence of potassium persulfate, lead to 2,4,5-trisubstituted oxazoles in good yields. Incidentally, 2-aminothiazoles are the products when ferric nitrate is employed instead of persulfate in the above reaction.

A facile one pot synthesis of thiazolo[3,2-a]benzimidazole and pyran fused polyheterocyclic scaffolds.

An efficient synthesis of dihydro-4H-benzo[4,5]imidazo[2,1-b]pyrano[2,3-d]thiazole by a multicomponent route starting from 2-((1H-benzo[d]imidazol-2-yl)thio)-1-phenylethan-1-one, an aromatic aldehyde and malononitrile is described. This protocol features a metal free approach with good substrate scope and decent yield. The heterocyclic skeleton obtained in this study may have interesting biological properties.

Synthesis of benzosuberone-tethered spirooxindoles: 1-3-dipolar cycloaddition of azomethine ylides and arylidene benzosuberones.

Expedient synthesis of benzosuberone-tethered spirooxindoles was accomplished by a three-component 1,3-dipolar cycloaddition reaction between azomethine ylide (generated in situ) and arylidene benzosuberone. This protocol offers good yield and wide functional group tolerance under mild reaction condition with high regio- and stereoselectivities.

Pineapple Peel-Derived Carbon Dots: Applications as Sensor, Molecular Keypad Lock, and Memory Device.

Herein, the fluorescent carbon dots (CDs) with blue emission were prepared by hydrothermal treatment using pineapple peel as a source of carbon. The as-prepared CDs exhibited turn-Off fluorescence behavior toward Hg and subsequent turn-On behavior for l-cysteine along with enhanced biocompatibility and negligible cytotoxicity for cell imaging. The practical applicability of carbon dots was used for the quantification of Hg in water.

A facile solvent-free three-component domino synthesis of novel 2,4-diaryl-5,6-dihydrobenzo[j][1,7]phenanthrolines.

A simple, efficient and green procedure for the synthesis of novel 2,4-diaryl-5,6-dihydrobenzo[j][1,7]phenanthrolines has been developed via a Krohnke-type one-pot three-component reaction of 2-[arylmethylidene]-3,4-dihydro-1(2H)-acridinones and (2-aryl-2-oxoethyl)pyridinium bromides in the presence of excess ammonium acetate in good yields under solvent-free conditions. Good functional group tolerance, high substrate scope and no column purification are the practical advantages of this methodology.

A facile stereoselective synthesis of dispiro-indeno pyrrolidine/pyrrolothiazole-thiochroman hybrids and evaluation of their antimycobacterial, anticancer and AchE inhibitory activities.

A facile stereoselective synthesis of novel dispiro indeno pyrrolidine/pyrrolothiazole-thiochroman hybrids has been achieved by 1,3-dipolar cycloaddition of azomethine ylides, generated in situ from ninhydrin and sarcosine/thiaproline, on a series of 3-benzylidenethiochroman-4-ones. The synthesised compounds were screened for their antimycobacterial, anticancer and AchE inhibition activities. Compound 4l (IC 1.

Hypervalent Iodine(III) Mediated Synthesis of 3-Substituted 5-Amino-1,2,4-thiadiazoles through Intramolecular Oxidative S-N Bond Formation.

An efficient synthesis of 3-substituted-5-arylamino-1,2,4-thiadiazoles through intramolecular oxidative S-N bond formation of imidoyl thioureas by phenyliodine(III) bis(trifluoroacetate) is reported. The protocol features a metal-free approach, broad substrate scope, very short reaction times, good to excellent yields, and simple starting materials.

Investigation on the reactivity of α-azidochalcones with carboxylic acids: Formation of α-amido-1,3-diketones and highly substituted 2-(trifluoromethyl)oxazoles.

The reaction of α-azidochalcones with carboxylic acids has been investigated resulting in the formation of α-amido-1,3-diketones under microwave irradiation via in situ formation of 2H-azirine intermediates. An interesting reaction is described wherein, with trifluoroacetic acid at lower temperature, it affords highly substituted 2-(trifluoromethyl)oxazoles. These flexible transformations proceed under solvent free conditions in good to excellent yields without any catalyst.

An efficient synthesis of N-substituted 3-nitrothiophen-2-amines.

A novel protocol for the synthesis of 3-nitro-N-aryl/alkylthiophen-2-amines in good yields from the reaction of α-nitroketene N,S-aryl/alkylaminoacetals and 1,4-dithiane-2,5-diol in the presence of K2CO3 in refluxing ethanol is described. This transformation generates two C-C bonds in a single operation and presumably proceeds through a reaction sequence comprising 2-mercaptoacetaldehyde generation, nucleophilic carbonyl addition, annelation and elimination steps.

1,3,5-Tri-p-tolyl-pentane-1,5-diol.

In the title compound, C26H30O2, the central benzene ring forms dihedral angles of 14.85 (15) and 28.17 (14)° with the terminal benzene rings.

Synthesis, molecular docking and cytotoxicity evaluation of novel 2-(4-amino-benzosulfonyl)-5H-benzo[b]carbazole-6,11-dione derivatives as histone deacetylase (HDAC8) inhibitors.

A new series of 2-(4-aminobenzosulfonyl)-5H-benzo[b]carbazole-6,11-dione derivatives, which has not been reported yet, has been synthesized from 1,4-naphthoquinone and 4-aminophenylsulfone involving an Michael addition, benzoylation and Pd catalyzed coupling. This set of compounds has been evaluated for in vitro cytotoxicity specifically against human cervical cancer cell line (SiHa) and most of the synthesized compounds exhibited good cytotoxic activity. Molecular docking of all the synthesized compounds was studied; among fourteen molecules docked compound 3 was the one with the best glide and E model score of -9.

Erbium triflate promoted multicomponent synthesis of highly substituted imidazoles.

The synthesis of highly substituted imidazole derivatives has been achieved from various α-azido chalcones, aryl aldehydes, and anilines. This multicomponent protocol employs erbium triflate as a catalyst resulting in excellent yield of the imidazoles.

1,5-Bis(4-chloro-phen-yl)-3-(4-methyl-phen-yl)pentane-1,5-dione.

In the title mol-ecule, C24H20Cl2O2, the central methyl-benzene ring forms dihedral angles of 42.47 (10) and 34.34 (10)° with the terminal 4-chloro-phenyl fragments.

4-(2-Hy-droxy-phen-yl)-3,5-di-thia-hepta-ne-dioic acid.

In the crystal of the title compound, C11H12O5S2, mol-ecules are linked by O-H⋯O hydrogen bonds and C-H⋯O inter-actions, forming a three-dimensional network.

(E)-3-(4-Meth-oxy-phen-yl)-3-[3-(4-meth-oxy-phen-yl)-1H-pyrazol-1-yl]prop-2-enal.

In the title mol-ecule, C20H18N2O3, the pyrazole ring forms a dihedral angle of 2.2 (1)° with its meth-oxy-phenyl substituent and a dihedral angle of 67.2 (1)° with the benzene substituent on the propenal unit.

1-(2,4-Dinitro-phen-yl)-3-phenyl-4-phenyl-sulfanyl-1H-pyrazole.

In the title mol-ecule, C(21)H(14)N(4)O(4)S, the pyrazole ring forms dihedral angles of 45.6 (1), 87.7 (1) and 27.

Copper(I)-catalyzed cascade sulfonimidate to sulfonamide rearrangement: synthesis of imidazo[1,2-a][1,4]diazepin-7(6H)-one.

A novel strategy of copper(I)-catalyzed cascade intramolecular nucleophilic attack on N-sulfonylketenimine followed by rearrangement of sulfonimidates to sulfonamides resulting in a library of substituted 8,9-dihydro-5H-imidazo[1,2-a][1,4]diazepin-7(6H)-ones has been developed.

5-(2-Nitro-1-phenyl-but-yl)-4-phenyl-1,2,3-selenadiazole.

In the title compound, C(18)H(17)N(3)O(2)Se, the selenadiazole ring is planar [maximum deviation = 0.012 (2) Å for the ring C atom bearing the phenyl substituent]. The dihedral angle between the selenadiazole ring and the attached benzene ring is 46.

Ethyl 2-phenyl-3-(4-phenyl-1,2,3-selenadiazol-5-yl)-3-p-tolyl-propano-ate.

In the title compound, C(26)H(24)N(2)O(2)Se, the selenadiazole ring is essentially planar [maximum deviation = 0.004 (3) Å]. The dihedral angle between the selenadiazole ring and the attached benzene ring is 50.

Camphorsulfonic acid catalysed facile tandem double Friedlander annulation protocol for the synthesis of phenoxy linked bisquinoline derivatives and discovery of antitubercular agents.

A series of phenoxy linked bisquinoline derivatives were synthesised from the Friedlander annulation of 2-(4-acetylphenoxy)-1-aryl-1-ethanones with 2-aminobenzophenone in good yields using (±)-camphor-10-sulfonic acid (CSA) as the catalyst. These compounds were screened for their in vitro activity against Mycobacterium tuberculosis H37Rv (MTB) and among the 23 compounds screened, 2-(3-bromophenyl)-6-chloro-3-[4-(6-chloro-4-phenyl-2-quinolyl)phenoxy]-4-phenylquinoline (3q) and 2-(4-bromophenyl)-6-chloro-3-[4-(6-chloro-4-phenyl-2-quinolyl)phenoxy]-4-phenylquinoline (3o) were found to be the most active compounds with MIC of 1.1 and 2.

SnCl2-catalyzed selective atom economic imino Diels-Alder reaction: synthesis of 2-(1H-pyrrolo[2,3-b]pyridin-3-yl)quinolines.

The synthesis of 2-(1H-pyrrolo[2,3-b]pyridin-3-yl)quinolines by a SnCl(2)-catalyzed multicomponent reaction has been described. The reaction proceeds chemo- and regioselectively in an atom-economic way, generating a library of 24 quinoline derivatives.

1-(2-Naphth-yl)-3-phenyl-3-(4,5,6,7-tetra-hydro-1,2,3-benzoselenadiazol-4-yl)propan-1-one.

In the title compound, C(25)H(22)N(2)OSe, the fused six-membered cyclo-hexene ring of the 4,5,6,7-tetra-hydro-1,2,3-benzoselenadiazole group adopts a near half-chair conformation and the five-membered 1,2,3-selenadiazole ring is essentially planar (r.m.s.

A facile synthesis of carbocycle-fused mono and bis-1,2,3-selenadiazoles and their antimicrobial and antimycobacterial studies.

A series of mono and bis-1,2,3-selenadiazole derivatives have been synthesized by the oxidative cyclization of mono and bis semicarbazones of 2-(3-oxo-1,3-diarylpropyl)-1-cyclohexanones using selenium(IV) oxide. The newly synthesized compounds were evaluated for their in vitro antimicrobial activity against Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 11632) and Candida albicans (ATCC 90028) and in vitro antituberculosis activity against Mycobacterium tuberculosis H37Rv (MTB). Among these compounds, 1,3-di(4-chlorophenyl)-3-(4,5,6,7-tetrahydro-1,2,3-benzoselenadiazol-4-yl)-1-propanone (2h) and 3-(4-chlorophenyl)-1-(4-methylphenyl)-3-(4,5,6,7-tetrahydro-1,2,3-benzoselenadiazol-4-yl)-1-propanone (2g) were found to be the most active compounds with MIC of 3.