Reference

Method of preparation of azaindole derivatives

All Rights Reserved. Method of preparation of azaindole derivatives. Liu, Wansheng; Patel, Sunil S.; Cuniere, Nicolas; Lear, Yvonne; Deshpande, Prashant P.; Simon, Jeffrey N.; Lai, Chiajen; Pullockaran, Annie J.; Soundararajan, Nachimuthu; Bien, Jeffrey T. (USA ).Some commonly used reagents like 7440-05-3 is used in this experiment. U.S. Pat. Appl. Publ. US 2007032503 A1 8 Feb 2007,23pp. (English). (United States of America). CODEN: USXXCO. INCL: 514253040; 544362000. APPLICATION: US 2006-492750 25 Jul 2006. PRIORITY: US 2005-705230P 3 Aug 2005. DOCUMENT TYPE: Patent CA Section: 28 (Heterocyclic Compounds (More Than One Hetero Atom)) Section cross-reference(s): 1 A method of prepg. azaindole compds., e.g. (I), for antiviral use against HIV-1 infection (no data), comprises bromination of 2-amino-4-methyl-3-nitropyridine by bromine in acetic acid in the presence of sodium acetate to give 2-amino-5-bromo-4-methyl-3-nitropyridine (II), diazotization and methoxylation of II by tert-Bu nitrite in methanolic HCl (generated from acetyl chloride and methanol) to give 5-bromo-2-methoxy-4-methyl-3-nitropyridine (III), condensation of III with N,N-dimethylformamide di-Me acetal in the presence of LiOMe in DMF to give 5-bromo-4-[2-(dimethylamino)ethenyl]-2-methoxy-3-nitropyridine (IV), methoxylation of IV with NaOMe in the presence of CuI, Me propionate, and NaOMe in THF/methanol under refluxing to give 2,5-dimethoxy-4-[2-(dimethylamino)ethenyl]-3-nitropyridine (V), catalytic hydrogenation of V in the presence of Pd/C in Et acetate followed by treatment with trimethylsilyl chloride in isopropanol at room temp. for 1 h to give 4,7-dimethoxypyrrolo[2,3-c]pyridine monohydrochloride (VI), Friedel-crafts acylation of VI with ClCOCO2Me in the presence of AlCl3 in MeNO2/CH2Cl2 to give 2-(4,7-dimethoxypyrrolo[2,3-c]pyridin-3-yl)-2-oxoacetic acid Me ester monohydrochloride (VII), and amidation of VII with 1-benzoylpiprazine in the presence of NaOBu in THF gave the desired product I. .