SM-307

The antidepressant 5-methyl-8-ethylsulfonyl-10-(2-dimethylaminoethyl) - 5H - dibenzo[b,e][1,4]diazepine - 11(10) - one (I) had lower toxicity in mice than imipramine or desipramine; the LD50 values were 73.9, 353.5, and 857.4 mg/kg after i.v., i.p. or oral administration into mice, resp.I did not change spontaneous activity in mice but showed property. corresponding to those of the tricyclic antidepressive substances.I was active against the effects of reserpine on body temperature and motor activity and enhanced the effects of catechol amines on body temperature and blood pressure.Peripheral anti-acetylcholine and antihistamine activities were very weak.I did not influence brain amine levels or monoamine oxidase activity.Cardiovascular and respiratory effects of I were very weak.