A General Synthesis of 4-Substituted 6-(2-Imidazolinylamino)-5,8-dimethylquinolines

Abstract

A general synthesis of 4-substituted 6-(2-imidazolinylamino)-5,8-dimethylquinolines 1 has been developed. All new compounds were synthesized from a common intermediate, 5,8-dimethyl-6-nitro-4-quinolone 3, the structure of which was confirmed by X-ray crystallography. This methodology involved the conversion of 3 into either a 4-chloro- or 4-bromoquinoline followed by the introduction of various 4-substituents late in the synthetic sequence. Substituents introduced in this way include alkyl (18a), alkoxy (12a, 12b), halo (9, 12c, 16), cyano (18b), thioalkyl (12d), acetamido (14), carboxamido (19), and hydroxy (10). This work illustrates the utility of 4-haloquinoline intermediates in the general synthesis of 4-substituted quinolines.

Efficient Synthesis of 2‐Arylamino‐2‐imidazolines and 2‐Ami‐ nobenzimidazoles with Aminoiminomethanesulfonic Acid Derivatives

“…8 Also, Mundla et al 9 have reported the synthesis of 2-arylamino-2-imidazolines by reacting an aromatic amine with N-acylated-2-methylthio-2-imidazoline. 10 Another methods for preparation of 2-arylamino-2-imidazolines are reaction of ethylenediamine with carbodiimide, 11 methyl N-arylthiocarbamate, and dimethyl N-aryldithiocarbonimidate. 12 Also, these compounds are prepared from reaction of cyanogens bromide with ethylenediamines.…”