Synthesis and anorectic activity of 2H-4,6-dimethyl-2-[(4-phenylpiperazin-1-yl)methyl]-3-oxo-2,3-dihydroisothiazolo[5,4-b]pyridine

The synthesis of 2H-4, 6-dimethyl-2-[(4-phenylpiperazin-1-yl)methyl]-3-oxo-2,3-dihydro-isothiazolo[5,4-b]pyridine (3) and its biological properties are described. Compound 3 pharmacologically evaluated in vivo by use of behavioral tests showed to have a profile of activity characteristic of stimulation of the central serotoninergic system, mostly 5-HT2A receptors (anorectic action: 2 mg/kg ip, 8.5 mg/kg po) However, receptor activity of isothiazolopyridine 3 was not confirmed in vitro using 5-HT2A and 5-HT1A, receptor binding technique. Molecular modeling studies demonstrated that it is difficult to predict bioactive conformation of title molecule 3.