In this study, three pyridine and four thiophene containing chalcone derivatives were synthesized via Claisen-Schmidt condensation reaction. Different spectral analyses (IR, ¹H NMR, HRMS) clarified the structures, and these proposed compounds were screened for antimicrobial activity by agar disk diffusion technique. Compound 1c was conspicuously active against most of the bacterial and fungal strains. It displayed higher activity against B. cereus (22.3 ± 0.6 mm), S. sonnei (43.3 ± 0.6 mm), and S. boydii (34.0 ± 1.0 mm) compared to the standard ceftriaxone (20.3 ± 0.6 mm, 40.3 ± 0.6 mm, and 25.7 ± 0.6 mm, respectively). In addition, the exhibited inhibition zone of compound 1c against all fungal strains was higher than the standard amphotericin B. All the newly synthesized derivatives satisfied the ADME properties, and no toxicological risks were found. All compounds were docked against three protein receptors with the range of binding affinities of -6.3 to -9.6 kcal/mol. Molecular dynamics simulation was scrutinized further for compound 1c in three protein-ligand complexes where RMSD and RMSF data were below 2 Å, proposing its stability inside and minimal structural changes.

Infrared (IR) spectra of the specimens were recorded on SHIMADZU IRTracer-100 infrared spectrophotometer running as KBr pellets. ¹H NMR (400 MHz) spectra of the samples were documented from a BRUKER NMR spectrometer using DMSO-d₆ as solvent. Chemical shift values (d values) were noted in ppm relative to the internal standard TMS, and coupling constant values (J) were symbolized in Hz. The spin multiplicities were represented in abbreviated form as s (singlet), d (doublet), t (triplet), q (quartet), and m (multiplet). High Resolution Mass Spectra were obtained using a JEOL JMS-700 MStation from the Instrumental Analysis Center, Kumamoto University, Kumamoto, Japan.