Arylomycins A and B, new biaryl-bridged lipopeptide antibiotics produced by Streptomyces sp Tu 6075 -: II.: Structure elucidation

The structures of new lipopeptide antibiotics, arylomycins A and B, were elucidated by a combination of ESI-FTICR-mass spectrometry, NMR spectroscopy, EDMAN sequencing, and fatty acid and chiral amino acid analyses. The colourless arylomycins A share the peptide sequence Of D-N-methylseryl(2)(D-MeSer(2))-D-alanyl(3)-glycyl(4)-N-methyl-4-hydroxyphenylglycyl(5)- (MeHpg(5))-L-alanyl(6)-tyrosine7 cyclised by a [3,3]biaryl bond between MeHpg(5) and Tyr(7). The yellow arylomycins B differ from arylomycins A by nitro substitution of Tyr(7). The N-termini of arylomycins A and B are acylated with saturated C(11)similar toC(15) fatty acids (fa(1)) comprising n, iso, and anteiso isomers. Arylomycins A and B represent the first examples of biaryl-bridged lipopeptides.