<unk>  is a tricyclic compound, specifically a dibenzothiepine, and possesses three rings fused together with a side chain attached in its chemical structure. It is the only TCA with a dibenzothiepine ring system to have been marketed. The drug is a tertiary amine TCA, with its side chain-demethylated metabolite northiaden (desmethyldosulepin) being a secondary amine. Other tertiary amine TCAs include amitriptyline, imipramine, clomipramine, doxepin, and trimipramine.<unk>  exhibits (E) and (Z) stereoisomerism like doxepin but in contrast the pure E or trans isomer is used medicinally. The drug is used commercially as the hydrochloride salt; the free base is not used.
Dosulepin
Pretomanid
Covaxin
Mucrocetin
Itruvone
Crotamiton
Celadrin 
Co-codaprin