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Vilsmeier-Haack (VH) formylation reactions with acetophenones are sluggish in acetonitrile medium even at elevated temperatures. However, millimolar concentrations of transition metal ions such as Cu(II), Ni(II), Co(II), and Cd(II) were found to exhibit efficient catalytic activity in Vilsmeier-Haack Reactions with acetophenones. Reactions are accelerated remarkably in the presence of transition metal ions. The VH reactions followed second order kinetics and afforded acetyl derivatives under kinetic conditions also irrespective of the nature of oxychloride (POCl3 or SOCl2) used for the preparation of VH reagent along with DMF. On the basis of UV-vis spectroscopic studies and kinetic observations, participation of a ternary precursor (M(II) S (VHR)) in the rate-limiting step has been proposed to explain the mechanism of the metal ion-catalyzed VH reaction. C

Among the title isoxazoles (II) and pyrazoles (IV), compound (IIi) shows the highest cytotoxic potential towards the COLO320 cancer cell lines.

Antimicrobial agents 4a–g and 5a–g with very good potency were synthesized with 100% ee from phenylpropanolamine (norephedrine) by BF3 catalyzed three components one pot Mannich reaction in good yields. Obtained compounds were characterized using spectral techniques. Antimicrobial study of these compounds revealed a good to very high potential activity against tested microbes when compared to standard antimicrobial drugs streptomycin and ketoconazole. These synthesized compounds exhibited significant minimum inhibitory concentration (MIC) values against Gram positive and Gram negative bacteria. Amongst compound 4b, 4c, 4d, 4e, 5a, and 5e exhibited very high potent MIC values against tested twelve bacteria and three fungi when compared to control. When subjected to molecular docking, in silico studies revealed significant binding energies ranging from −7.06 to −8.90 kcal/mol for all obtained compounds towards target receptor DNA topoisomerase IV and amongst compounds 4b and 4d have shown maximum binding energies 8.70 and 8.90 kcal/mol, respectively.

An efficient diversity oriented synthesis of [1,2,3]triazolo[1,5-a][1,4]benzodiazepines has been developed by sequential diazotization, azidation and cycloaddition reactions in a one-pot fashion. This strategy allows an easy accessibility of triazole fused [1,4]benzodiazepines in good yields. The main objective of this methodology is to introduce various substituents at all possible positions under mild reaction conditions. All the synthesized compounds were evaluated for their antimicrobial, anticancer and in silico activity. Among the tested compounds (2a–n), the derivatives 2a, 2b, 2d, 2k, 2g, 2j, 2m and 2l have displayed a broad spectrum of antibacterial activity. Anticancer activity results revealed that compounds 2a, 2g and 2m exhibited potent in vitro anticancer activity against A549 lung adenocarcinoma cancer cell line. Further, molecular docking studies of all the synthesized compounds were performed to gain a comprehensive understanding of the plausible binding modes and also to compare the theoretical and experimental results of these compounds.

A variety of novel spirooxindole-pyrrolidine derivatives are synthesized by 1,3-dipolar cycloaddition reactions of azomethine ylides derived from isatin and sarcosine or thiaproline with acrylonitriles (I).

The title compounds (IV) and (VI) are obtained via 1,3-dipolar cycloaddition of an azomethine ylide generated from isatin and sarcosine with dipolarophiles.

1,3-Dipolar cycloaddition of azomethine ylides, generated in situ via decarboxylative condensation of isatins (I) and (IX) and sarcosine (II) or (L)-proline (X), to naphthoquinone (III), followed by spontaneous dehydrogenation afford the spirooxindoles (IV) and (XI), resp., in high yields.

With similar yields also Mn(acac)3, [Ni(NH3)6]Cl2, [Ni(en)3]S2O3 or Hg[Co(SCN)4] transition metal complexes can be used.

The novel method uses a thermal three-component reaction of isatins, amino acids and 3-phenyl-5-isoxazoline and can be extended to ninhydrin as substrate.