PROCESS FOR THE SYNTHESIS OF METHYL-5(6)-N,N-DISUBSTITUTED AMINO CARBAMAMOYL BENZIMIDAZOLE-2-CARBAMATES

摘要

A process for the synthesis of methyl 5 (6)-N, N-disubstituted amino carbamoyl benzimidazole-2-carbamitescomprising reacting 4+acetamido-3-nitro-benzoic acid of formula (I)with thionyl chloride and treating the reaction mixture was a secondary amine of formula (2) in the presence of organic aromatic hydrocarbon solvent to obtain 4-N, N-disubstituted-amino-carbamoyl-2-nitro acetamilide of formula (II);subjecting the compound of formula (II) to alkaline hydrolysis in the presence of an organic alkanol solvent to form 4-N, N-disubstituted amino carbamoyl-2-nitroanilines formula (III),subjecting the same to reduction in the presence of Ra Ni and alkanol with hydrogen to obtain 4-N, N-disubstituted amino carbamoyl-O-phenylenediamines of formula (IV)of then treating the compound of formula (IV) with methoxy=carbonyl-S-methyl isothioures of yield the final compound of formula (V) wherein, NRR is diethyl amino, propyl amine, diisopropyl amino, diisobutyl amino, morboline piperidino, N-phenyl piperazino or N-(2-pyridyl)-verazine groups.