Synthesis and Properties of New Conjugates of Isatin and Bicyclic Monoterpenes

Conjugates of isatin and hydrazones based on (+)-camphor and (–)-fenchone were synthesized for the first time. The physicochemical properties of the synthesized compounds have been studied, and for the hydrazone product of fenchone and isatin X-ray diffraction data have been obtained. Molecular modeling of the possible interaction of new compounds with the active site of the basic protease 3CLpro of the SARS-CoV-2 virus was carried out, and the properties of isatin-terpene compounds as inhibitors of the 3CLpro protease were studied. It was found that the new conjugates do not exhibit inhibitory properties against 3CLpro, which makes it possible to clarify the direction of further chemical modifications of monoterpenoid derivatives in order to obtain molecules with antiviral properties.