β-Carbolines: synthesis of harmane, harmine alkaloids and their structural analogs by thermolysis of 4-aryl-3-azidopyridines and investigation of their optical properties

Efficient Synthesis of Pyrido[3,4-c]cinnolines and Pyrido[3,2-c]cinnolines by Intramolecular Azo Coupling Reaction of 4,6-Diaryl-3-pyridine Diazonium Salts and Study of Their Antiviral Activity

“…Hantzsch pyridines were prepared in one step by the reaction of chalcones with 3-aminocrotononitrile (see SI). 14 15 For the synthesis of nicotinamides 10a – h , partial alkaline hydrolysis of the cyano group of pyridines was used (see SI). 3-Aminopyridines 11a – h were prepared by the Hoffmann rearrangement of nicotinamides 10a – h using sodium hypochlorite.…”

“…[16][17][18] Hantzsch nitropyridines 15a-i with two electron-withdrawing groups in the 3,5 positions of the pyridine ring were synthesized in two stages. 14,15 At the first stage, the Michael addition of enamine to the nitrochalcone double bond conjugated with the acceptor group took place; subsequent cyclocondensation resulted in the formation of 1,4-Scheme 2 Synthesis of pyrido [3,4-c]cinnolines by intramolecular azo coupling reaction of 4,6-diarylpyridine-3-diazonium salts dihydropyridine. The oxidation of dihydropyridine was carried out with sodium nitrite.…”

“…Monitoring of reactions and purity of the compounds obtained was by TLC on Silufol UV-254 plates, visualization under UV light. All chemicals were of analytical grade and purchased from Sigma-Aldrich Chemical Co. 2-Nitro-1-phenylethan-1-ones, 21` b c d substituted chalcones 15 , 22a–d and β-nitroenones 23a,b were synthesized according to the described procedures.…”

Recent synthetic strategies for the construction of functionalized carbazoles and their heterocyclic motifs enabled by Lewis acids

“…1). [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] In recent years, many research groups have remarkably found that carbazole derivative have divergent biological applications such as affinity to bind with estrogen receptors, 52 anti-tumor activity, [53][54][55][56] antiplasmodial, 57 antimalarial, 58 antibiotic, 59 antifungal, 60,61 etc. Besides their biological applications, they also have bioimaging properties, applications in developing OLEDs, [46][47][48][49] OFETs, 41 solardyes, 43 conducting polymers, 37 photovoltaic devices, 39 optoelectric properties, 38,40 and organic semiconductors.…”

“…1). 1–19 In recent years, many research groups have focused on the difficult synthesis of annulated carbazole scaffolds using Lewis acid-mediated methods which have applications in bio-medical and pharmaceutical fields. 20–27 However several catalytic and non-catalytic methods have been discovered for the formation of the annulated carbazoles.…”