The syntheses, characterizations, and biological activities of three organoplatinum compounds, each containing a triazole ring, are discussed. These organometallic compounds demonstrate superior cytotoxicity against osteosarcoma and human breast cancer cells relative to cisplatin, a well-known chemotherapeutic agent used for chemotherapy.

Three new dimeric bis-guanidinate zinc­(II) alkyl, halide, and hydride complexes [LZnEt] 2 (1), [LZnI] 2 (2) and [LZnH] 2 (3) were prepared. Compound 3 was successfully employed for the hydrosilylation and hydroboration of a vast number of ketones. The catalytic performance of 3 in the hydroboration of acetophenone exhibits a turnover frequency, reaching up to 5800 h–1, outperforming that of reported zinc hydride catalysts. Notably, both intra- and intermolecular chemoselective hydrosilylation and hydroboration reactions have been investigated.

Two new irregular hexagons (6 and 7) were synthesized from a pyrazine motif containing an organometallic acceptor clip [bearing platinum(II) centers] and different neutral donor ligands (4,4'-bipyridine or pyrazine) using a coordination-driven self-assembly protocol. The two-dimensional supramolecules were characterized by multinuclear NMR, mass spectrometry, and elemental analyses. Additionally, one of the macrocycles (6) was characterized by single-crystal X-ray analyses. Macrocycles are unique examples of [2 + 2] self-assembled ensembles that are hexagonal but irregular in shape. These hexagon frameworks require the assembly of only four tectons/subunits. The cytotoxicity of platinum(II)-based macrocycles was studied using various cell lines such as A549 (human lung carcinoma), KB (human oral cancer), MCF7 (human breast cancer), and HaCaT (human skin keratinocyte) cell lines, and the results were compared with those of cisplatin. The smaller macrocycle (7) exhibited a higher cytotoxic effect against all cell types, and its sensitivity was found to be comparable with that of cisplatin for A549 and MCF7 cells. Cell cycle analysis and live propidium iodide staining suggest that the macrocycles 6 and 7 induced a loss of membrane integrity that ultimately might lead to necrotic cell death.

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The synthesis and characterization of a new pyrazine-based ditopic organoplatinum(II) complex having a bite angle of 180°is reported. The facile and efficient syntheses are described of three discrete neutral Fe(II)/Pt(II) heterobimetallic SCCs with Pt(II) acceptor clips of different binding angles, 0, 120, and 180°. These new SCCs were characterized by multinuclear NMR and mass spectrometry. Electrochemical response of these ferrocene containing self-assembled ensembles was studied using cyclic voltammetry. The diplatinum acceptor organometallic clips significantly quench the fluorescence of highly emitting carbon quantum dots (CD), while the self-assembled macrocycles tend to nullify the quenching effect of the organometallic clips. Interestingly, the inefficient quenching of CD fluorescence by these SCCs was found to be directly related to the angular disposition of the binding sites in the Pt(II) based organometallic clips.