Assembly of New Heterocycles through an Effective Use of Bisaldehydes by Using a Sequential GBB/Ugi Reaction
Tanpreet Kaur1, Ram Nayan Gautam1, Anuj Sharma2
1D-305, Medicinal Chemistry Lab, Department of Chemistry, Indian Institute of Technology, Roorkee, 247667, India.
Abstract:
A facile route for the assembly of new bis-heterocyclic imidazo[2,1-b][1,3]thiazinyl/benzothiazoyl-phenyl)benzamide scaffolds through a two-step Groebke-Blackburn-Bienaymé (GBB)/Ugi reaction sequence is reported, which establishes multiple points of diversity in the final products. The highlights of this procedure are the survival of the aldehyde group following the GBB reaction without the need for additional protection/deprotection steps. Moreover, the reaction is operationally simple, with the absence of any catalyst, and exhibits excellent functional-group tolerance under minutes of microwave irradiation.
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