261895-32-3Relevant academic research and scientific papers
Concise Total Syntheses of Pyrido[4,3-b]carbazole Alkaloids Using Copper-Mediated 6π-Electrocyclization
Itoh, Tomoki,Abe, Takumi,Choshi, Tominari,Nishiyama, Takashi,Yanada, Reiko,Ishikura, Minoru
, p. 2290 - 2299 (2016/05/19)
Concise syntheses of 9-methoxyellipticine, 3,4-dihydroellipticine (μ-alkaloid D), 1,2,3,4-tetrahydroellipticine, 2-methyl-1,2,3,4-tetrahydroellipticine, olivacine, 3,4-dihydroolivacine, (±)-guatambuine, and (±)-janetine were developed starting from hexatriene intermediates readily obtained by Pd-catalyzed tandem cyclization/cross-coupling reaction of indolylborates. The route enables the facile construction of pyrido[4,3-b]carbazoles by Cu-catalyzed 6π-electrocyclization and subsequent transformation of the pyridocarbazole intermediates into pyrido[4,3-b]carbazole alkaloids. Concise total syntheses of pyrido[4,3-b]carbazole alkaloids were accomplished using Cu-catalyzed 6π-electrocyclization of hexatriene as a key step.
A novel entry to pyrido[4,3-b]carbazoles: An efficient synthesis of ellipticine
Ishikura, Minoru,Hino, Ayako,Yaginuma, Toshikatsu,Agata, Isao,Katagiri, Nobuya
, p. 193 - 207 (2007/10/03)
The palladium catalyzed tandem cyclization-cross-coupling reaction of indolylborate (2) with vinyl bromide (9) was developed for the preparation of pyrido[4,3-b]carbazole as a key reaction. The cross-coupling reaction of 2a provided hexatriene (10), and then cyclization of 10 to pyrido[4,3- b]carbazole (12) was effected with irradiation or Lewis acid. Using indolylborate (2c) for the cross-coupling reaction, a novel construction of ellipticine was attained through similar reaction sequences.
Palladium Catalysed Cross-Coupling Reaction with Indolylborate: A Concise Access to Ellipticine Derivatives
Ishikura, Minoru,Yaginuma, Toshikatsu,Agata, Isao,Miwa, Yoshihisa,Yanada, Reiko,Taga, Tooru
, p. 214 - 216 (2007/10/03)
A novel approach to ellipticine derivatives is described. The palladium catalysed cross-coupling reaction of indolylborate 1 with vinylbromides 4 gives hexatrienes 5, which are subsequently converted to pyrido[4,3-b]carbazoles. In addition, the acid promoted spiroannelation reaction of hexatrienes 5 is observed to give spiroindoles 9.
