Inhibitors of enzymes cholinesterases are recognized as one of the main choices for reducing symptoms of Alzheimer's disease, the fourth leading cause of death in developed countries, because they cause an increase in the level of acetylcholine neurotransmitter in cholinergic synapses. In order to discover even more effective cholinesterase inhibitors, new derivatives of 1,3-thiazole-thienostilbenes 1-9 and their photoproducts 10-16 were synthesized in this study. Compounds 1-5, 7, and 8 were synthesized through the Wittig reaction with thiophene phosphonium salt. The synthesis of 1,3-thiazole-thienostilbene 6 was carried out by amidation of compound 5 with acetic anhydride, while compound 9 was synthesized by Büchwald-Hartwig amination. All derivatives 1-9 were gained as mixtures of cis- and trans-isomers. The obtained compounds 1-4 and 6-9 underwent electrocyclic reactions in a Rayonet photoreactor equipped with 10 UV lamps at 300 nm, resulting in new derivatives of thienobenzo-thiazoles 10-16. New derivatives of thienobenzo-triazoles 23-25 were also synthesized, through a series of three reactions. All obtained compounds were purified using column chromatography on silica gel. Pure compounds were characterized by spectroscopic methods and sent for biological activity testing. 1H and 13C NMR techniques, UV-Vis spectroscopy, mass spectrometry, and HRMS analyses were used. Computational research was also conducted to study the geometries and electronic structures of the obtained thiazoles, and molecular docking was performed to identify interactions between the enzyme and the potential inhibitor in order to predict the strength of the inhibition.