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Several valuable biologically active molecules can be obtained through C–H activation processes. However, the use of expensive and not readily accessible catalysts complicates the process of pharmacological application of these compounds. A plausible way to overcome this issue is developing and using cheaper, more accessible, and equally effective catalysts. First-row transition (3d) metals have shown to be important catalysts in this matter. This review summarizes the use of 3d metal catalysts in C–H activation processes to obtain potentially (or proved) biologically active compounds.

The current manuscript describes the catalysts in click chemistry reactions, mechanism insights and use of other metals beyond copper associated with Azide-Alkyne Cycloadditions (AAC). Due to their biological importance and several applications in various areas of science, significant efforts have been devoted to devise robust methods for the synthesis of triazoles. Among these approaches, azide-alkyne cycloadditions strategy has been consolidated as a powerful tool for preparing this class of heterocycles. Herein, click reactions involving catalysis with metals other than copper are presented and critically discussed.

International audience; A heterogeneous catalyst was assembled with ruthenium nanoparticles on carbon nanotubes and used in a mild oxidation method to prepare sulfones from sulfides. The system proved very efficient on the investigated substrates and the products were obtained in high yields.

Diverse examples are provided of enantioselective sequences for the transformation of cycloalkenes to either chiral trans-β-substituted cycloalkanols or chiral α-amino ketones.

The comparison in several reaction conditions for synthesis of nonracemic α-methylsulfinylation of 3,4-dihydronaphthalen-1(2H)-one was achieved. The sulfanylation reactions of 3,4-dihydronaphthalen-1(2H)-one-O-methyloxime and 2-(methylsulfinyl)-3,4-dihydronaphthalen-1(2H)-one-O-methyloxime by homogenous reaction medium are reported. The products were obtained in good yields and de. The yields, diastereoselectivity and theoretical calculations to all obtained compounds to support the experimental data are compared and discussed.

We report the synthesis and fluorescent properties of 1,4-disubstituted-1,2,3-triazoles (1a-c) based on pollutant wastes and by-products from the cashew and biodiesel industries as a design for fluorescent markers. The triazoles were synthesized in four steps; catalytic hydrogenation of cardanol, reaction with epichlorohydrin, azide substitution and/or epoxide opening and, Cu catalyzed click-chemistry of the azide with the ethynylanilines (6a-c). This procedure is a potential alternative to make fluorescent markers since it affords the intermediates in high yields, enabling one to produce the products in good quantities. Moreover, triazolazobenzenes (8a-c) were prepared by azo coupling of the trizoles (1a-c) with phenol to give a new option of dyes. Evaluation of the fluorescent properties of the achieved compounds showed that all triazole derivatives displayed good fluorescence emissions in the range of 325–400 nm, with a maximum of fluorescence intensity at around 350 nm when excited between 225 and 300 nm; besides, the para-triazolaniline exhibited a dual fluorescence emission, presenting an additional emission band in the blue range (400–500 nm).

A new and practical method has been developed for the transformation of racemic α-bromo ketones to chiral α-azido and α-amino ketones with high enantioselectivity using phase transfer, ion-pair mediated reactions with a recoverable chiral quaternary salt (10 mol %) as catalyst in fluorobenzene-water. The process has been generalized to a variety of other attachments including of C, O, S, and NHR.

Compounds featuring weakly-coordinating N-oxides or carbonyl groups, as for instance, quinoline N-oxide and quinonoid systems represent important structural scaffolds with potential biological activities. Due to their biological importance, significant efforts have been devoted to devise robust methods for their step-economical preparation. Among these approaches, the C–H activation strategy has emerged as a powerful, versatile and efficient tool in molecular sciences. This feature article summarizes recent key advances in transition-metal-catalyzed C–H functionalization for A-ring functionalization of heterocyclic and quinoidal compounds by challenging weakly-coordinating entities, published prior to May 2018.

Background/aim In recent years, the search for new anticancer experimental agents derived from natural products or synthetic analogues, such as resorcinolic lipids, has received increased attention. The present study aimed to evaluate the antitumor potential, describe the cell death mechanism and the effects of 3-Heptyl-3,4,6-trimethoxy-3Hisobenzofuran-1-one (AMS35AA) in combination with different chemotherapeutic agents in the MCF-7 cell line. Materials and methods Analysis of cytotoxic, genotoxic, membrane integrity, cell death and gene expression induced by the compound was performed. Results The AMS35AA and its association with 5-FU demonstrated reduction of cell viability; increase of cell death; enhancement of genomic damage and accumulation of cells in G2/M phase. Conclusion AMS35AA has potential for breast cancer treatment since it is capable of exerting cytotoxic and cytostatic effects in a breast cell line and also could be an adjuvant in cancer therapy when combined with 5-FU.