ABSTRACT
Differentiation can also be made between such antibiotics on the basis of the carbohydrate components, linked singly or in a combined form to the tri- and tetracyclic heptapeptide aglycones. Recent knowledge emphasizes the essential role of carbohydrates in the recognition and communication processes between living cells by invariable structural arrangement. Acid hydrolysis gives the amorphous free aminodeoxy sugars, whereas methanolysis yields the crystalline methyl glycosides. Since the molecular mass of these carbohydrate derivatives amounts at most, to a hundredth pari of the molecular weight of the antibiotics, their isolation calls for the most advanced techniques. In most of the cases, however, only indirect methods can be applied to the determination of the site of aglycone-carbohydrate linkages. Nowadays one of the most popular and dynamically developing fields of carbohydrate research is the synthesis of oligosaccharides, clearly as a result of the outstanding biological importance of these compounds.
