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Diabetes mellitus (DM) is a chronic metabolic disorder posing a significant health risk. Effective treatments are continually sought. Coumarin derivatives with oxime ester groups have shown potential as antidiabetic agents by inhibiting the α-glucosidase enzyme, a key player in glycoprotein metabolism and postprandial hyperglycemia control. This makes lysosomal α-glucosidase a promising therapeutic target. A study used 28 coumarin derivatives with known α-glucosidase inhibitory IC50 values for computer-assisted drug design (CADD) through quantitative structure-activity relationship (QSAR) analysis, yielding a statistically robust equation for guiding new compound development. Subsequently, eleven new coumarin derivatives with oxime ester groups were synthesized, showing enhanced α-glucosidase inhibitory activity compared to the initial set. Molecular docking assays indicated that compounds 32, 37, 38, and 39 had lower free energy values than the native ligand, suggesting higher stability in target protein interactions. Notably, compound 38 had the lowest free energy (-8.351) and demonstrated lower root mean square deviation (RMSD) and root mean square fluctuation (RMSF) than the original ligand, indicating greater stability. The QSAR equation derived is: Log IC50 = 2.886 - 0.054 (LUMO) + 0.073 (μ) – 0.148 (α) – 0.046 (RD) + 0.046 (BM) + 0.001 (Vvdw) – 0.421 (qC2) + 1.138 (qC8) – 0.092 (qC9) + 2.61 (qC10) + 1.354 (qN1) (Eq 1) n=28; R=0.918; R²=0.843; SD=0.196; F calc/F tab=3.169; Sig =<0.01; PRESS = 1.376. Compound 38’s SMILES notation is: C\C(=N/OC(=O)\C=C/C1=CC=C(Br)C=C1)C1=CC2=CC(O)=C(CC(O)=O)C=C2OC1=O). [ABSTRACT FROM AUTHOR]

This study focuses on the mutual interaction of substituents in the nucleophile and substrate – cross interaction constant, ρXY, in the uncatalyzed aminolysis by substituting pyridine with phenyl carbonyl isothiocyanate. The mechanism was found to be a stepwise process with a rate-limiting breakdown of the –NCS leaving group. This stepwise reaction mechanism considers the cross-interaction constant (CIC) with rate-limiting breakdown of tetrahedral intermediate in gas and solvent phases. The corresponding Hammett coefficients are related to the substituents associated with (1) the nucleophiles (X), ρX (−1.93 to −6.54 for the gas phase and 10.5 to 18.9 in the solvent model), and with (2) the substituents associated with the phenyl ring of the substrate (Y), ρY (0.41–3.48 for the gas phase and 1.83 to −10.70 for the solvent model). It also includes the Brønsted coefficient with X, βX (0.11–1.52 for the gas phase and −2.57 to 3.96 for the solvent model), and CIC values, ρXY (0.69 for the gas phase and 0.87 for the solvent model). In this work, the NBO analysis, reaction potential, reaction electronic flux (REF), dual descriptor, and the structure-energy relationships were considered in interpreting the mechanistic criteria. [ABSTRACT FROM AUTHOR]