Resin acid derivatives: fungicidal properties and prediction of the spectrum of biological activity

Biologically active substances that confer antiviral, anti-tumour and antimicrobial effects, which are found among the components of plant raw materials, as well as the products of their chemical modification, are the subject of considerable research interest. These objects include tricyclic diterpenoids – extractives of wood of abietic and pimaric types (resin acids). The presence of two reaction centres (double bonds and a carboxyl group) in the structure of resin acids opens up a wide range of possibilities for synthesising useful compounds on their basis. One of the most promising areas for the study of resin acids and their derivatives consists assessing their fungicidal properties to inform their introduction into compositions as additives, as well as in the application of protective films to increase the resistance of composite building materials against the aggressive effects of microorganisms. In the present work, the fungicidal activity of the N-phenylimide of maleopimaric acid and its polyfluoroalkyl ethers synthesised by us was evaluated on the cells of the filamentous fungi Aspergillus niger, Alternaria alternata and Penicillium sp. by the rate of colony formation and growth. A comparative analysis of the biological activity of resin acids and their in silico derivatives was performed. According to the AntiBag Pred forecast, the test compounds having the maximum values of the probabilities of the presence and absence of each type of activity are characterised by the manifestation of antibacterial activity in relation to strains of gram-positive bacteria. The results of the predictive model are consistent with previous experimental data. However, AntiFun Pred data related to the calculation of fungicidal activity were not confirmed in vitro.