title: Desilylative activation of TMSCN in chemoselective Strecker-Ugi type reaction: functional fused imidazoles as building blocks as an entry route to annulated purines.
abstract: A pathway of desilylative activation of TMSCN as a functional isonitrile equivalent, and DABCO-THF as an appropriate system for activation in a chemoselective Strecker-Ugi type reaction, has rendered ethyl glyoxalate and various heterocyclic-2-amidines as feasible substrates, and afforded the successful synthesis of 3-amino-2-carboxyethyl substituted fused imidazoles as useful building blocks. This class of functional scaffold has provided, via construction of the fused pyrimidinone motif, the synthesis of biologically important C8-N9 annulated purines, adenines and their oxo/thio analogs. This new approach is convenient and flexible for the preparation of versatile purine-condensed heterocycles.
authors.affiliation: Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S. A. S. Nagar, Mohali - 160062, Punjab, India. skguchhait@niper.ac.in.
authors.forename: Sankar K
authors.initials: SK
authors.lastname: Guchhait
authors.forename: Vikas
authors.initials: V
authors.lastname: Chaudhary
mesh_terms: D000578:Amidines / Q000138:chemical synthesis; D002384:Catalysis; D003486:Cyanides / Q000737:chemistry*; D006038:Glyoxylates / Q000138:chemical synthesis; D007093:Imidazoles / Q000737:chemistry*; D015394:Molecular Structure; D010879:Piperazines / Q000737:chemistry; D011687:Purines / Q000138:chemical synthesis*; D014297:Trimethylsilyl Compounds / Q000737:chemistry*
chemical_list: D000578:Amidines; D003486:Cyanides; D006038:Glyoxylates; D007093:Imidazoles; D010879:Piperazines; D011687:Purines; D014297:Trimethylsilyl Compounds; C579385:ethyl glyoxalate; C058010:trimethylsilyl cyanide; C007306:triethylenediamine