Novel frentizole-based indolyl thiourea analogues were prepared as potential MAO/ABAD inhibitors. Compound 19 displayed low micromolar and high nanomolar IC50 value for MAO-A and MAO-B inhibition. Compounds 17 and 21 showed important structural features for future design of ABAD inhibitors. Several reported compounds acted as low micromolar HRP inhibitors. The active compounds demonstrated low cytotoxicity profile.