(((5-phenylthiophen-2-yl) methylene) amino) phenol derivatives were synthezised and characterized by IR and NMR. The density functional theory (DFT) method with 6–311++G (d,p) basis set was used for both calculations of molecular geometries and spectroscopic parameters. Frontier molecular orbitals and molecular electrostatic potential maps for compounds 1a, 1b and 1c were obtained. Due to the differences observed in the theoretical spectral parameters, N–H⋯O type intermolecular/intramolecular hydrogen bonds in the molecular structures of compounds were proposed. To determine the nonlinear optical properties of compounds, the mean polarizability (α) and the first hyperpolarizability (β) obtained as 44.2388 × 10 −24 esu and 373.1267 × 10 −31 esu for compound 1a, 43.8141 × 10 −24 esu and 195.2893 × 10 −31 esu for compound 1b, 36.9489 × 10 −24 esu and 120.73825 × 10 −31 esu for compound 1c, respectively were used. These values indicate that compounds can be suggested as a good nonlinear optical material. In addition, the antimicrobial properties of compounds were investigated by considering antileishmanial and antibacterial activities. The compounds were evaluated against Leishmania infantum promastigots for antileishmanial activity and against five standard bacteria (Escherichia coli, Shigella flexneri, Yersinia enterocolitica, Salmonella typhimurium and Salmonella enterica) for antibacterial activity, by microdilution broth assay with Alamar Blue Dye. Results show that only compound 1a has high antileishmanial activity and can be evaluated in leishmaniasis treatment after in vivo studies and also considered in pharmacological studies for antibacterial activity.