Abstract:
The elaboration of a 6,6-spiroacetal scaffold to incorporate a triazole unit as a peptide bond surrogate at the anomeric position is described. The novel spiroacetal-triazole hybrid structures were generated viacycloaddition of a spiroacetal azide to a series of alkynes. The spiroacetal framework was constructed viaBarbier reaction of bromide10 with Weinreb amide11, followed by acid-catalysed deprotection and cyclisation to afford the 6,6-spiroacetal ring system. The resultant ethoxy-spiroacetal8 was converted to spiroacetal azide5, which was then elaborated into a series of spiroacetal-triazole derivatives 7.
