In this HOT paper, Blagg and coworkers at the Institute of Cancer Research, Sutton, report an efficient C2-functionalisation via direct C–H arylation for N3-MEM-protected imidazo[4,5-b]pyridines. The imidazo[4,5-b]pyridine heterocycle is a versatile purine isostere and important ring system which has seen a recent growth in medicinal chemistry application of potential therapeutic benefit; for example in protein kinase inhibitors for the treatment of cancer, inflammatory disease and diabetes. This methodology allows easy access to 2,7- and 2,6-disubstituted derivatives from common intermediates in an approach amenable to the divergent synthesis of analogues and which is applicable to rapid medicinal chemistry exploration of this emerging purine isostere.
Regioselective C2-arylation of imidazo[4,5-b]pyridines
Jonathan Macdonald, Victoria Oldfield, Vassilios Bavetsias and Julian Blagg
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