Total synthesis of pyrrolo[2,3-c]quinoline alkaloid: trigonoine B

• Takashi Nishiyama,
• Erina Hamada,
• Daishi Ishii,
• Yuuto Kihara,
• Nanase Choshi,
• Natsumi Nakanishi,
• Mari Murakami,
• Kimiko Taninaka,
• Noriyuki Hatae and
• Tominari Choshi

Beilstein J. Org. Chem. 2021, 17, 730–736, doi:10.3762/bjoc.17.62

• ]. We have previously reported the total syntheses of indolo[3,2-c]quinoline (isocryptolepine) [19], azaanthracenones (kalasinamide, marcanine A, and geovanine) [20], imidazo[4',5':4,5]pyrido[2,3-b]indole (grossularine-1 and -2) [21][22], imidazo[4,5-b]pyridine (2-amino-1-methyl-6-phenylimidazo[4,5-b

• synthesis of 2-aminopyridine derivatives through an electrocyclization of conjugated carbodiimides derived from an aza-Wittig reaction of iminophosphoranes and isocyanates [27]. Hibino and co-workers also achieved the preparation of mutagenic amino-α-carbolines (2-amino-9H-pyrido[2,3-b]indole, AαC) and

An intramolecular inverse electron demand Diels–Alder approach to annulated α-carbolines

• Zhiyuan Ma,
• Feng Ni,
• Grace H. C. Woo,
• Sie-Mun Lo,
• Philip M. Roveto,
• Scott E. Schaus and
• John K. Snyder

Beilstein J. Org. Chem. 2012, 8, 829–840, doi:10.3762/bjoc.8.93

• library of eighty-eight α-carbolines was prepared by using this robust methodology for biological evaluation. Keywords: α-carboline; chemical diversity; inverse electron demand Diels–Alder; isatin; pyrido[2,3-b]indole; 1,2,4-triazine; Introduction In comparison with the well-known β-carbolines, α

• -carboline alkaloids are quite rare, and only a few natural products isolated to date contain this pyrido[2,3-b]indole (α-carboline, 1, Figure 1) core. The most prominent examples are grossularine-1 (2) and grossularine-2 (3), which are marine cytotoxic agents that were isolated from the tunicate Dendrodoa