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Updated: Jun 30, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Organocatalytic Multicomponent Reactions Using 1,1-Diaminobenzalazine: Synthesis of Pyrano[2,3-c]pyrazoles and
Kriti Mehta1, Anamika Kumari1, Prasad V Bharatam1
1Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, Mohali, Punjab 160062, India.
Abstract:
An efficient organocatalytic multicomponent reaction (OMCR) for the synthesis of pyrano[2,3-c]pyrazole and pyranochromene derivatives utilizing 1,1-diaminobenzalazine as an organocatalyst has been reported. The uniqueness of this protocol lies in its broad functional-group tolerance, showcasing the use of activated ketones bearing a trifluoromethyl group and prefunctionalized sulfonamide-based pyrazolones as key substrates. The catalyst could be recycled up to 5 cycles with only a minimal loss of yield. Mechanistic insights provided by DFT studies confirmed the importance and bifunctional character of the organocatalyst. Green chemistry metrics benchmark this process as a step forward in the development of environmentally friendly and scalable methodologies, contributing to the broader goal of sustainable pharmaceutical synthesis.
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