Fig. 6: Preparation of compounds 3‒5.

a Synthesis of compound 3. 4-Biphenylacetonitrile and 9-anthraldehyde were added to methanol, followed by NaOH, and stirred for 4 h at room temperature. The resulting crude product was purified by column chromatography using dichloromethane (DCM) as an eluent to obtain compound 3. b Synthesis of compound 4. 2-(4-Aminophenyl)–3-(furan-2-yl)acrylonitrile and 2-hydroxy-5-methylbenzaldehyde were dissolved in ethanol. After refluxing for 6 h, the resultant mixture was cooled down to room temperature, filtered, and washed with ethanol. The crude product was purified by column chromatography using DCM and petroleum ether as the eluent to produce compound 4. c Synthesis of compound 5. 4-Fluorophenylacetonitrile and 1-naphthaldehyde were added to methanol, followed by NaOH, and stirred for 1 h at room temperature. The resulting crude product was purified by column chromatography using DCM as eluent to obtain compound 5.