Synthesis of 2-substituted-3-nitroimidazo[1,2-b]pyridazines as potential biologically active agents

摘要

A new heterocyclic reductive alkylating agent, 6-chloro-2-chloromethyl-3-nitroimidazo[1,2-b]pyridazine, was synthesized for the first time. It was shown to react under phase-transfer catalysis conditions with 2-nitropropane anion by an S(RN)1 mechanism to give excellent yield of isopropylidene derivative formed from a base-promoted nitrous acid elimination of C-alkylation product. Extension of this S(RN)1 reaction to various nitronate anions led to a new class of 3-nitroimidazo[1,2-b]pyridazine derivatives bearing a trisubstituted double bond at the 2-position. [References: 30]