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Thymidine was oxidised with potassium permanganate at pH 8.5 at 37° and the products separated by paper chromatography. The following were identified: 5,6-dihydroxy-5,6-dihydrothymidine (‘thymidine glycol’), N-(2-deoxy-D-ribofuranosyl)-N′-pyruvoylurea, N-formylurea, and urea. A component, probably 2-deoxy-D-ribofuranosylurea was detected but it amounted to less than 4% of the reaction products. In addition were present three acidic products probably produced by the oxidation of the primary alcohol group at position 5′. Almost no 2-deoxy-D-ribose was present so it apparently must also have been oxidised to acidic products. 5,6-Dihydroxy-5,6-dihydrothymidine was obtained also by oxidation of thymidine with osmium tetroxide and barium chlorate.

Structure (XXIII) is suggested for ostreogrycin A, an antibiotic produced by the soil organism Streptomyces ostreogriseus. Acid hydrolysis of “perhydro A,” prepared by complete hydrogenation of the antibiotic, yields inter alia 4,6-dimethyl-γ-heptanolactone, DL-alanine, proline, and 10-amino-7-methyl-δ-dec-2-enolactone. Ozonolysis of the antibiotic with oxidative working-up yields glycine and β-alanine, while reductive ozonolysis yields methyl glyoxal and 2,4-dimethylpent-2-enal. The production of small quantities of glycine and serine on hydrolysis of ostreogrycin A and its reduction products is explained by the presence of an oxazole ring system in the antibiotic.

An equilibration between cobinamide and neocobinamide with K≈ 1 occurs under highly acidic conditions. Similar equilibrations are reported with cobyric acid, other monocarboxylic acids, a dicarboxylic acid fraction, dehydrocobinamide, and with vitamin B12 itself. The last process gives neovitamin B12, which has been crystallised. Compounds of the neo-series resemble rather closely the analogous normal compounds, except in chiroptical properties.Methanolysis of vitamin B12 and of neocobinamide gives heptamethyl dicyanocobyrinate and heptamethyl dicyanoneocobyrinate, respectively, the mass spectra of which suggest that they are isomeric. This is confirmed by the X-ray analysis of neovitamin B12 which shows it to be cyano-13-epicobalamin. In relation to the naturally derived corrinoids known so far, the neo-compounds are thus epimeric at C-13.