[en] Two disaccharides have previously been obtained in high yield from the cell wall of S. aureus by the use of hydrolytic enzymes. Disaccharide 1 is N-acetylglucosaminyl-N-acetylmuramic acid and disaccharide 2 is N-acetylglucosaminyl-N,Ogr;-diacetylmuramic acid. After hydrolysis of disaccharide 2 with β-acetylglucosaminidase, N,O-diacetylmuramic acid was prepd. Data obtained from periodate oxidn. of these compds. coupled with their susceptibility to β-acetylglucosaminidase indicate that both disaccharides are β-1,4-linked and that the O-acetyl group of disaccharide 2 is on the 6-position of N-acetylmuramic acid. The high reducing power and pos. Morgan-Elson reaction of the disaccharides are due to their unusual susceptibility to hydrolysis at alk. pH. These and other anomalous properties of the compds. are discussed. [on SciFinder(R)]