Synthesis and biological activity of derivatives of glycopeptide antibiotics eremomycin and vancomycin nitrosated, acylated or carbamoylated at the N-terminal

Nitrosation, carbamoylation or acylation of the glycopeptide antibiotics eremomycin or vancomycin produced series of derivatives substituted at the N-terminus of the peptides. Though the modified amino group in these derivatives is not capable of protonation, N-nitroso derivatives retain antibacterial activity in vitro and in vivo. N-Carbamoyleremomycin has low activity, and N-Cbz-eremomycin and N-Boc-eremomycin are devoid of antibacterial activity, both in vitro and in vivo.