A new series of 7-(2-(benzo[d]thiazol-2-ylamino)ethoxy)-4-methyl-2H-chromen-2-one derivatives(4a4k) was synthesized and evaluated for their D2 and 51HT2 antagonistic activity as a measure of atypical antipsychotic properly. Compounds 7-(2-(benzo[d]thiazo/-2-ylamino)ethoxy)-4-methyl-2H-chromen-2- one derivatives (4a-4k) was synthesized by refluxing 2-amino benzothiazoles substituted derivatives (3a3k) and 7-(2-Chloroethoxy)-4-melhyl-2H-chromen-2-one (2) in dry pyridine. The synthesized compounds were characterized with the help of spectral and analytical data. Most of these compounds showed dopamine D2 receptor antagonistic activity from moderate to high potency along with serotonin 5-HT2 receptor blockage activity: a property that has been suggested to be necessary for the atypical nature of antipsychotic agents. The D2 and 5-HT2 receptor blockage activity was evaluated by inhibition of apomorphine-induced climbing behavior and 5HTP induced head twitches in mice respectively.