Assembly of Di-, Tetra- and Hexanuclear Organostannoxanes Using Hemi Labile Intramolecular N→Sn Coordination: Synthesis, Structure, DFT and Antibacterial Studies

Four-membered C^N chelation in main-group organometallic chemistry

Main-group organometallic compounds containing four-membered C^N chelating rings are being studied because of the interest in harnessing the enhanced reactivity of such compounds which arises as a result of the release of steric strain. In this article, we have reviewed the literature on these systems. This review is organised in terms of the types of ligand systems that allow the assembly of such compounds, viz., compounds containing aliphatic amine motifs, pyridine motifs and aniline motifs. In addition to a discussion on the synthesis and structure, we also examine the reactivity and applications of the main-group element compounds involved. In particular, applications involving H₂ activation, carbonyl activation, olefin reduction, C-H activation, hydroalumination, cyanamide oligomerisation, borylation of olefins and heteroarenes, isocyanate activation and C-C bond activation are discussed.

Review on the Developments of Benzothiazole-containing Antimicrobial Agents

The infectious diseases caused by bacterial resistance to antibiotics constitute an increasing threat to human health on a global scale. An increasing number of infections, including tuberculosis, pneumonia, salmonellosis and gonorrhea, are becoming progressively challenging to cure owing to the ineffectiveness of current clinically used antibiotics and presents a serious health threat worldwide in medical community. The major concern of this global health threat is the ability of microorganisms to develop one or several mechanisms of resistance to antibiotics, making them inefficient to therapeutic treatment. The quest for discovering novel scaffold with antimicrobial property is particularly in great need to face future challenges in hospital and healthcare settings. Hence, the development of benzothiazoles is of considerable interest to medicinal chemists. Benzothiazole, being part of an important class of heterocyclic scaffold retains a wide spectrum of various attractive pharmacological activities. Antibiotic resistance represents an increasing burden comprising medical cost, hospital stay and mortality. Several derivatives containing a benzothiazole scaffold, reported in the literature, were found to display remarkable potencies towards diverse Grampositive and Gram-negative bacterial pathogens. The principal focus concerns the antibacterial potential of benzothiazole-based derivatives as antimicrobial agents interacting with targets in bacterial pathogens. In this review, we also disclose the significance of the benzothiazole moiety in the discovery of new antibacterial compounds, the potential of benzothiazole-based derivatives in the case of resistant bacterial strains, optimization of their antibacterial activity, and their future perspectives. The structure-activity relationship study and the mode of action of the title derivatives are highlighted too.