Thermal behavior and determination of physicochemical properties of novel candidates for antipsychotic drugs

Treatment of schizophrenia with currently available drugs is often ineffective or results in several adverse reactions. In previous studies focusing on the search for new antipsychotic drugs, we designed and obtained a series of dopamine D2 and serotonin 5-HT1A and 5-HT2A receptor ligands that were pharmacologically evaluated and showed promising antipsychotic activity. Evaluation of ADMET parameters is an important issue in drug development and should be performed at its early stage to avoid developing molecules with poor pharmacokinetics, that are unlikely to enter the market. For this reason, in this work we focused on the assessment of physicochemical parameters of selected compounds from the series we obtained to assess their drug-like potential. The results of thermal analysis showed that most of the tested compounds are thermally stable above 200 degrees C, with one compound stable up to 190 degrees C. Permeability through biological membranes assessed in the parallel artificial membrane permeability assay indicated that all tested compounds effectively migrate through biological membranes by means of passive diffusion. The solubility of the tested compounds was determined in PBS, reflecting physiological pH, and 0.01 M HCl, indicating their low to moderate solubility in PBS, which was significantly improved in acidic environment. The lipophilicity of the studied compounds expressed as LogD falls within the range of 1.84-2.80, what suggest that they would show good oral absorption and the ability to cross lipid barriers. The studies were supplemented with in silico prediction of ADMET parameters, which also indicate the probable high drug-likeness of the tested compounds.