Structural studies on the antibiotic vancomycin; the nature of the aromatic rings
It is shown that the antibiotic vancomycin contains five benzene rings. In a three-ring unit, connected through ether linkages, two sugars (glucose and vancosamine) are sequentially attached to a central pyrogallol system. A two-ring unit is connected as a biphenyl system, incorporating three phenolic OH groups. It is concluded that vancomycin contains carbamoyl and carboxy-groups. The identified units, plus the previously isolated aspartic acid and N-terminal N-methyl-elucine, appear to account for all, or almost all the carbon skeleton of vancomycin if reasonable assumptions are made regarding interconnection of the units through amide bonds.