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Updated: Oct 3, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
A General Synthesis of 4-Substituted 6-(2-Imidazolinylamino)-5,8-dimethylquinolines
Pamela E. Outt1, Jeffrey J. Ares, George E. Roberts
1Procter & Gamble Pharmaceuticals, Health Care Research Center, 8700 Mason-Montgomery Rd, Mason, Ohio 45040-9462, and Procter & Gamble Company, Miami Valley Laboratories, P.O. Box 538707, Cincinnati, Ohio 45253-8707.
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.
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