Investigative studies on the formation of the imidazo [4′,5′:3,4]pyrido[2,3-b]indole ring: Formal synthesis of the alkaloids grossularines-1 and 2. X-Ray crystal structures of 5-indol-3-yl-imidazole and bisimidazocarbazole derivatives

Biomimetic Synthesis of Grossularines‐1

“…In the approach of Hibino and co‐workers, the construction of the tetracyclic pyrido[2,3‐ b ]indole ring system proceeded in a linear manner through the use of Pd‐catalyzed cross‐coupling reactions of halogenated indoles and metallated imidazoles. A formal synthesis of 1 has been reported by Molina et al4 that intersects the key intermediate reported by Hibino and co‐workers. Herein we describe a remarkably concise biomimetic synthesis of 1 and 2 that is based on a novel oxidative dimerization–electrocyclization sequence of 2‐amino‐4‐(3‐indolyl)imidazoles 5 and 6 derived from oxotryptamine ( 3 ).…”

Biomimetic Synthesis of Grossularines‐1

“…[3] In the approach of Hibino and co-workers, the construction of the tetracyclic pyrido [2,3-b]indole ring system proceeded in a linear manner through the use of Pd-catalyzed cross-coupling reactions of halogenated indoles and metallated imidazoles. A formal synthesis of 1 has been reported by Molina et al [4] that intersects the key intermediate reported by Hibino and co-workers. Herein we describe a remarkably concise biomimetic synthesis of 1 and 2 that is based on a novel oxidative dimerization-electrocyclization sequence of 2-amino-4-(3-indolyl)imidazoles 5 and 6 derived from oxotryptamine (3).…”

Structural, Vibrational, and Electronic Properties of the Glucoalkaloid Strictosidine: A Combined Experimental and Theoretical Study

“…Geometry Optimization. Because no crystallographic data for strictosidine are available, the geometry optimization data, which were calculated using the B3LYP/6-31G(d) and B3LYP/6-311++G(2d,p) basis set, were compared with the Xray data for similar structures [26][27][28][29]. Due to the similarity of the data obtained from both basis sets (Table 1), the discussion that follows is based on the B3LYP 6-31G(d) values but should also apply to B3LYP 6-311++G(2d,p).…”