Synthetic study of muraymycins using Ugi-four component reaction.

The synthetic study of muraymycins (MRYs), which have potent antibacterial activity, is described. The key elements of our approach include the synthesis of L-epicapreomycidine via a C-H amination reaction and a conversient assemblage to construct of the framework of muraymycins using Ugi-four component reaction. First, isonitrile 4 was prepared from uridine in 14 steps. The precursor of carboxylic acid component 15 was synthesised via the C-H amination reaction, formation of cyclic guanidine structure. Muraymycin D2 analogs were synthesized by a model Ugi-four component reaction.