Preparation of a Pt(II)–3-Hydroxy-2-tolyl-4H-chromen-4-one Complex Having Antimicrobial, Anticancerous, and Radical Scavenging Activities with Related Computational Studies

[Image: see text] A novel benzopyran-based platinum (II)–3-hydroxy-2-tolyl-4H-chromen-4-one (HToC) complex has been prepared and studied by UV–visible spectrophotometry. The study is based on the colored complexation between Pt(II) and HToC in the pH range of 8.92–9.21, resulting in the formation of a stable binary yellow complex exhibiting λ(max) at 509–525 nm. The formed complex maintains linearity between 0.0 and 1.8 μg Pt(II) mL(–1). The well-known qualitative analytical methods, including Job’s method of continuous variations and the mole ratio approach, have both proven that the stoichiometry of the complex is 1:2 [Pt(II)/HToC]. Hence, the analytical results suggest that the formed platinum complex exhibits a square planar geometry. The values of various attributes corresponding to spectrophotometric studies and statistical calculations, such as the molar extinction coefficient (6.790 × 10(4) L mol(–1) cm(–1)), Sandell’s sensitivity (0.0029 μg Pt(II) cm(–2)), standard deviation (± 0.0011), RSD (0.317%), limit of detection (0.0147 μg mL(–1)) and correlation coefficient (0.9999), show that the performed study satisfies all of the criteria for good sensitivity, versatility, and cost-effectiveness. In order to have an apprehension of the molecular geometry and other structural specifics of the complex, DFT studies have been carried out. The in vitro anticancer potential of the ligand and its platinum complex in the human breast cancer cell line (T-27D), as determined by the MTT assay, reveals that the complex has better antiproliferative potential than the ligand. The antimicrobial potential of the complex has been successfully tested against both Gram-positive and -negative bacteria. Antioxidant capacity results suggest the better radical scavenging capacity of the complex than that of the ligand.