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The four component reactions involving diazoamides, amines, aldehydes, exomethylenes/imines were performed in the presence of copper(I) thiophenecarboxylate as a catalyst to afford dispiroindolo-pyrrolidine/-imidazolidine derivatives in good yield with regio-, chemo- and diastereoselective manner. The structure and stereochemistry of dispiroheterocyclic ring systems were confirmed based on the representative single-crystal X-ray analysis. These reactions involve the generation of intermolecular azomethine ylide intermediates and the subsequent 1,3-dipolar cycloaddition process with olefins or imines.

Investigations of regio-, chemo- and diastereoselective studies on three- as well as four-component reactions using diazooxindoles, imines, aldehydes, amines, alkenes, alkynes or diazenes in the presence of copper(I) thiophene-2-carboxylate are performed to furnish spiroindolo-pyrrolidine/-imidazolidine/-triazolidine ring systems in good yields. A mixture of products was obtained when unsymmetrical alkenes were used as dipolarophiles. This study demonstrates the successful generation of intermolecular azomethine ylides from copper(I) carbenoids and their subsequent 1,3-dipolar cycloaddition reactions with various dipolarophiles, such as olefins (CC), imines (CN), diazenes (NN) in a stereoselective manner. Single-crystal X-ray analyses were performed to establish unambiguously the structure and stereochemistry of spiroheterocyclic ring systems.

A simple, green, efficient and three-component procedure has been developed for the synthesis of 4′-phenyl-1′ H -spiro[indoline-3,2′-quinazolin]-2-ones ( 4a – m and 6a – g ) and 2,4-diphenyl-1,2-dihydroquinazolines ( 8a – l ) by the reaction of 2-aminobenzophenones, isatins or aromatic benzaldehydes and ammonium acetate in excellent yields under catalyst-free conditions using ethanol as a solvent. This method provides several advantages such as operational simplicity, higher yields, shorter reaction time and catalyst-free conditions with ethanol as a solvent makes the method eco-friendly as well as economical. All the 4′-phenyl-1′ H -spiro[indoline-3,2′-quinazolin]-2-ones were tested for antimicrobial activity against both Gram-positive and Gram-negative bacterial strains including a fungal strain Candida albicans MTCC 3017. Among these, the compounds 4f , 6a , 6c and 6g showed appreciable antibacterial activity with MIC values 7.8 μg/ml selectively against Gram-positive bacteria, Micrococcus luteus MTCC 2470. On the other hand, compounds 4j , 4m , 6c and 6g showed good activity with MIC values ranging between 3.9 and 7.8 μg/ml against Gram-negative bacteria, Klebsiella planticola MTCC 530.

The title compounds are screened for their anticancer activity against A549, MCF7, HeLa, and DU145 human cancer cell lines.

An efficient and mild InBr3-catalyzed approach to synthesize 2,3-dihydroquinazolin-4(1H)-one derivatives (3a–3aa) has been developed. Notably, all the products were isolated by recrystallization an...

A simple and facile synthesis of a series of novel pyrano[2,3-d]pyrimidines has been achieved successfully via the one-pot three-component reaction of 2-amino-7-methyl-5-oxo-4-phenyl-4,5-dihydropyrano[4,3-b]pyran-3-carbonitriles, DMF-DMA and arylamines in the presence of 1-butyl-3-methylhydrogensulphate [Bmim]HSO4 ionic liquid. This method has several advantages such as high yields, clean reaction, simple methodology and short reaction times. The synthesized compounds were evaluated for their antimicrobial activity against Gram-positive, Gram-negative and different Candida strains. Among the derivatives screened, compounds 4c, 4d, 4h and 4l were found to be active against both bacterial and Candida strains with MIC values ranging from 3.9 to 31.2 μg mL−1. In addition, compound 4l showed a good minimum bactericidal concentration, minimum fungicidal concentration and anti-biofilm activities. Furthermore, the mode of the antifungal action for the promising compound 4l was evaluated in C. albicans MTCC 1637 through an ergosterol biosynthesis inhibition process.

Among all the tested compounds (IV), derivative (IVe) appears to be the most potent sample with respect to antimicrobial, MBC and anti bio-film activities.

Various of the novel title compounds (III) (16 examples) display potent antimicrobial activities, e.g. (IIIa-c), (IIIg), (IIIi), as well as very good anti-biofilm activity.

A new catalyst Ti(IV)-salan system efficiently promotes the diastereo- and enantioselective monoepoxidation of conjugated dienes using H2O2 even in the presence of other olefins and adjacent stereocenters.

A variety of new polyazaheterocycles (III) are synthesized via Cu(I)-catalyzed azide-alkyne cycloaddition reactions.

The title compound (I) shows cytotoxic activity against HeLa, A549, DU145 and HepG2 cell lines and antimicrobial activity against Staphylococcus aureus MLS-16 MTCC 2940 and Bacillus subtilis MTCC 121.

Derivatives (IIIa), (IIIe), and (IIIf) exhibit promising cytotoxicity against different human cancer cell lines.

Title compound (IIIa) exhibits promising cytotoxicity against all the four cancer cell lines tested, while derivative (IIIb) shows significant cytotoxicity against HeLa and MDA-MB-231 cell lines.

The propargyl alcohol on reaction with aldoxime and NaOCl in DCM gave exclusively (3-arylisoxazol-5-yl) methanol 1. The compound 1 was oxidized to an aldehyde 2 followed by reaction with aniline resulted in Schiff's base 3. The compounds 3 were further reacted with various aldehydes having α-hydrogen using molecular iodine as catalyst and which yielded 5-(3-alkylquinolin-2-yl)-3-aryl isoxazole derivatives 4. All the final compounds 4 were screened against four human cancer cell lines (A549, COLO 205, MDA-MB 231 and PC-3) and among these compounds 4n showed potent cytotoxicity against all the cell lines at IC50 values of

A variety of highly functionalized pyrimidinylmethylchromene derivatives (IV) (22 examples) are synthesized via a one-pot three-component reaction.

Novel regiomer of herbarumin I (I) exhibits significant cytotoxic activities against five human cancer cell lines, especially against human colon carcinoma and human breast adenocarcinoma.

Two series of novel benzothiazolopyrimidine carboxamide derivatives (VI) and (VII) are synthesized and evaluated for their cytotoxicity against some human cancer cell lines.

The title compounds (V), (VII), and (IX) are synthesized starting from amine (I) via selective N-alkylation with bromoacetate (II), followed by reaction with various primary aliphatic amines, cyclic secondary amines amino acids.

Title compound (VIII) is synthesized starting from (L)-(-)-malic acid (I) with 84% syn selectivity.

A broad range of chromeno-annulated cis-fused pyrano[4,3-c]isoxazole derivatives is synthesized via a catalyst-free PEG mediated 1,3 cycloaddition employing in situ generated benzylic nitrones is presented.

Hitherto unreported fluorinated pyranochromene (IV) and pyranopyran derivatives (VI) are synthesized via simple multicomponent reactions and evaluated for their cytotoxicity against a panel of human tumor cell lines.

Two new diterpenoids, multifidanol (I) and multifidenol (II), are isolated together with several known compounds.

Mild, efficient and racemization-free synthesis of N-protected α, β-unsaturated γ-amino esters with unprecedented high E- stereoselectivity is described. This method is found to be compatible with Boc-, Fmoc- and other side chain protecting groups. The crystal conformations of the vinylogous γ-amino esters in monomers and in homo- and mixed dipeptides are studied. Further, the vinylogous homo-dipeptide showed a β-sheet conformation, while mixed α- and α,β-unsaturated γ-hybrid dipeptide adapted an irregular structure in single crystals.

Methoxydecanoic acid (VIIa) and methoxyundecanoic acid (VIIb) are synthesized both in racemic and stereoselective form.

A series of alkynyl epoxides is converted into the bicyclic ketals as mixtures of diastereomers under catalysis of cationic Au(I) generated from a combination of AuCl(PPh3) and AgSbF6.

Various types of substrates are used as efficient precursors for the synthesis of indoles via imine formation with aldehydes followed by base-promoted cyclization.

A 2,2-Bis(ethoxycarbonyl) vinyl- (BECV) group was used for the selective protection of amines at room temperature in the presence of potentially interfering functional groups such as OH, SH, COOH as well as other NH(2) groups. Several functional group transformations such as esterification, O-alkylation, O-acylation, N-alkylation, N-acylation, S-alkylation can selectively be carried out in the presence of the BECV group. The selective deprotection of the BECV group was achieved in a short time using ethylenediamine at room temperature while several other functional groups such as benzoate, aliphatic esters, amides and ethers remain intact. The BECV group shows orthogonal stability against the common protecting groups such as Fmoc, Cbz and Boc.

Littorachalcone (1) and diacid 10 were synthesized by direct routes. The antibacterial activity of 1, 10 and synthetic precursors were evaluated. Dialdehyde 3a showed potent antibacterial activity.

A new synthetic method has been developed and demonstrated for the utilization of commercially cheap MnO2 for the production of nanoparticles of LiMn2O4 spinel as a cathode material for Li-ion batteries. The process involves the insertion of lithium into electrolytic manganese dioxide (EMD) in an aqueous medium with glucose as a mild reductant in open air. The material resulting from calcination is pure, spinel-structured Li0.96Mn2O4 particles of sub-micrometric and nanometric size that exhibit promising electrochemical behavior in nonaqueous Li-salt solutions. Further development of this process may be interesting for the commercial production of LiMn2O4 for Li-ion batteries.