5‐Styrylisoxazoles: π‐Conjugated System with Fluorescent Properties and Bioactivity

A simple two‐step protocol for the synthesis of 3‐aryl/hetaryl‐4‐nitro‐5‐styrylisoxazole was elaborated. A large series of novel 5‐styrylisoxazoles (36 compounds) containing various substituents at positions 3 and 5 of isoxazole cycle was obtained. The title compounds revealed fluorescent properties in visible region, possessing emission maximum up to 610nm. The effect of solvatochromism and chemosensor properties towards a number of metal cations were demonstrated. Cytotoxic activity against MCF‐7 (breast carcinoma), HCT‐116 (colon carcinoma), A549 (pulmonary carcinoma) and WI38 (fibroblasts from lung tissue) cell lines was tested and toxicity in the concentration range of 10–100 μM was found for several compounds. A large series of novel fluorescent 3‐aryl\hetaryl‐4‐nitro‐5‐styrylisoxazoles was designed and synthesized. A systematic study of the effect of substituents in the positions 3 and 5 isoxazole cycle on the photophysical properties has been carried out. For the obtained compounds the detector properties, cytotoxicity in the concentration range of 10–100 μM and the effect of solvatochromism were found.