Skeletal Diverse Synthesis of N-Fused Polycyclic Heterocycles via the Sequence of Ugi-Type MCR and CuI-Catalyzed Coupling/Tandem Pictet–Spengler Reaction

• Published in: Journal of organic chemistry Vol. 77; no. 3; pp. 1414 - 1421
• Main Authors: Tyagi, Vikas, Khan, Shahnawaz, Bajpai, Vikas, Gauniyal, Harsh M, Kumar, Brijesh, Chauhan, Prem M. S
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 03-02-2012
• Subjects: Aldehydes - chemistry; Catalysis; Chemistry Techniques, Synthetic - methods; Copper - chemistry; Heterocyclic Compounds - chemical synthesis; Heterocyclic Compounds - chemistry; Iodides - chemistry; Polycyclic Compounds - chemical synthesis; Polycyclic Compounds - chemistry
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo202255v

Several diversity-oriented syntheses of N-fused polycyclic heterocycles have been demonstrated but most of them are based on point diversity within the same library and usually involve time-consuming sequential multistep syntheses, which also suffer from low yields and/or poor precursor scopes. We have developed a new strategy for the syntheses of skeletal diverse N-fused polycyclic compounds via an Ugi-type MCR followed by a CuI-catalyzed coupling reaction or tandem Pictet–Spengler reaction. This two-step sequence provides eight distinct skeleton of fused {6–5–5–6}, {5–5–5–6}, {6–5–6–6}, and {5–5–6–6} ring systems that have applications in medicinal chemistry and chemical genetics too.