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

Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow 226 001, India.
The Journal of Organic Chemistry (Impact Factor: 4.64). 02/2012; 77(3):1414-21. DOI: 10.1021/jo202255v
Source: PubMed

ABSTRACT 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.

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Available from: Vikas Tyagi, Jan 16, 2015
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