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Aromatic acids with three benzene nuclei bound through oxygen were obtained from actinoidin and ristomycin on their oxydation with permanganates of methylated aglycones and peptides. The structures of the methyl esters of these acids were determined by spectral methods. They are the following: methyl-3,5-bis-(4-methoxycarbonyl-phenoxy)-4-methoxybenzoate (from ristomycin) and methyl-3-(2-chlor-4-methoxycarbonyl-phenoxy)-5-(4-methoxycarbonyl-phenoxy)-4-methoxybenzoate (from actinoidin). The compounds are the aromatic parts of the molecules of the unusual triaminotricarboxylic amino acids present in the aglycones of all antibiotics of the group of polycyclic glycopeptides.

The method of exhaustive methylation with diasomethane was used as applied for actinoidines A and B and their glycosides for elucidation of the problem of connection between the carbohydrates and oxyaromatic fragments of the antibiotics followed by analysis of the acid hydrolyzates of the methoxy derivatives. It was found that the disaccarhide branch, i.e. 2-O-(L-acozaminyl)-D-glucose was connected in actinoidines A and B through the phenol group of the triaminotricarbonic fragment V, while the residue of D-mannose was connected through one of the phenol groups of the actinoidinic amino acid. The other two phenolic groups of the actinoidinic amino acid, as well as the phenolic groups of the N-end amino acids did not participate ion formation of the glycoside bonds. Actinosamine was probably connected through the alcohol group of the aglycone.

The quantitative amino acid composition of ristomycin A, a glycopeptide antibiotic, peptides I-IV (from partial acid hydrolysis of the antibiotic) and their dinitrophenylic derivatives was determined. It was shown that both ristomycin and free peptides I-IV contained one residue of ristomycinic acid and one residue of actinoidinic acid, diamino-dicarbonic amino acids of the glycylphenolic type. Peptides I-IV had close molecular weights, i.e. 1100-1200 and differed from each other in the gradually increasing numbers of NH2- and COON- groups, from one in peptide I to four in peptide IV. The quantitative amino acid analysis of the dinitrophenylic derivatives of ristomycin and peptides I-IV showed that the free NH2-group in peptide I belonged to ristomycinic acid, the same as in the antibiotic, while in peptides III-IV at least one of the free NH2-groups belonged to ristomycinic acid and the other belonged to actinoidinic acid.