Catalyst-free synthesis, antimicrobial evaluation, DFT, and molecular docking studies of novel spiro benzo[d]pyrrolo[2,1-b] thiazole-1,2′-indene ′-indene hybrids

This research paper focuses on a novel, rapid, facile and highly efficient catalyst-free multi-component reaction of benzothiazole core 1 , with 2-bromo-1,3-indandione 2 in the presence of acetylenic esters 3 for the synthesis of 1 ',3 '-dioxo-1 ',3 '-dihydro-3aH-spiro[benzo[d]pyrrolo[2,1-b]thiazole-1,2 '-indene]-3-carboxylate ' ,3 '-dioxo-1 ' ,3 '-dihydro-3a H-spiro[benzo[ d ]pyrrolo[2,1- b ]thiazole-1,2 '-indene]-3-carboxylate derivatives 4a-i. . This method was completed at ambient temperature in only 8 h with excellent yields, utilizing mild reaction conditions and cost-effective starting materials. Full confirmation of the synthesized compounds was obtained by a range of spectroscopic and analytical techniques, such as elemental analysis, 1 HNMR, 13 CNMR, IR, and MS. The described structure of 4a was subjected to structural and electronic investigation, as well as 1 H and 13C C chemical shifts, which were computed using the Gaussian 09 package and the B3LYP/6-311++G ++G (d, p) level of density functional theory (DFT) approach. The DFT study set out to allocate spectroscopic data in a way that made sense. The calculated DFT data are in close agreement with the experimental data. Several bacterial strains were used to assess the produced compounds' antibacterial properties. Certain substances demonstrated antibacterial activity that was either equivalent to or superior to the reference medications, gentamicin, and ciprofloxacin. Molecular docking research was also conducted on the chosen chemicals. According to the ADMET study of the synthesized molecules, structures 4a, 4d and 4g show the most promise as drug-like molecules.