Synthesis and pharmacological evaluation of novel naphthoquinone derivatives containing 1,2,4-triazine and 1,2,4-triazole moieties of methylene blue on the surface of a "core–shell" type catalyst for the Fenton system

Novel naphthoquinone derivatives bearing 1,2,4-triazine- (4a–b) and 1,2,4-triazole (5a–e) pharmacophores have been synthesized; their structure was confirmed by electrospray ionization mass spectrometry, 1H NMR, 13C NMR, IR spectroscopies and elemental analysis. The obtained heterocyclic compounds were estimated for their anticonvulsant activity on models of chemical- and electrical-induced seizures in pentylenetetrazole (PTZ) and maximal electroshock (MES) tests, respectively. Forced swimming test was used to evaluate the antidepressant effect of the naphthoquinone derivatives under study. Compounds 4a–b and 5a–e (100 mg kg–1) demonstrated anticonvulsant action comparable with valproic acid in PTZ-test and prevented the death of 100% of mice in MES model at 3 h and 24 h after oral administration. Moreover, these derivatives showed prolonged antidepressant-like properties, significantly reducing the duration of immobility time in comparison with the reference drug amitriptyline.