Synthesis and biological evaluation of certain 4‐alkylamino and 4‐arylalkylamino derivatives of the imidazo[4,5‐d]pyridazine and v‐triazolo[4,5‐d]pyridazine ring systems

Abstract

AbstractCertain 4‐alkylamino and 4‐arylalkylamino derivatives of the imidazo‐ and v‐triazolo[4,5‐d]pyridazine ring systems were prepared and evaluated against two human colon carcinomas (DLD‐1 and HCT‐15) and one human lung carcinoma (LX‐1), in vitro. 4‐Methylthioimidazo[4,5‐d]pyridazine (1) and 4‐methylthio‐v‐triazolo‐[4,5‐d]pyridazine (9) served as precursors to the title compounds. Treatment of these heterocycles with the appropriate amine (ammonia, methylamine, dimethylamine, benzylamine and hydrazine) provided the desired derivatives of that ring system. 4‐AIP (2) and 2‐aza‐4‐AIP (10) served as precursors to the 4‐dimethylaminomethyleneamino derivatives 6 and 14, respectively. Likewise, the 4‐hydrazino analogs (7 and 15) served as intermediates in the syntheses of benzaldehyde‐p‐[bis(2‐chloroethyl)amino]amino[4,5‐d]‐pyridazin‐4‐yl‐hydrazone (8) and benzaldehyde‐p‐[bis(2‐chloroethyl)amino]amino‐v‐triazolo[4,5‐d]pyridazin‐4‐yl‐hydrazone (16), respectively.