Azinothricin was isolated from the culture filtrate of Streptomyces sp. X-14950 in crystalline form. It represents a new type of hexadepsipeptide antibiotic as it contains a 19-membered cyclodepsipeptide ring composed of six unusual amino acids and bearing a novel C21 side chain. Azinothricin was identified as [(3S, 4S, 7R(S*), 10S, 17R, 20S, 23R)[2S(2'R*, 5'S*, 6'S*)3S*]]-α-ethyl - 6 -(3-ethyl-1, 5-dimethyl-4-oxo-1, 5-heptadienyl)- N-(1, 8, 14, 15, 18, 21, 27-heptaaza-21-hydroxy- 7-(1-hydroxyethyl) -2, 6, 9, 16, 19, 22-hexaoxo 4-isopropyl-20-(methoxymethyl)-17, 18-dimethyl-5-oxatricyclo[21.4.0.010, 15]heptacosan-3-yl)tetrahydro-α, 2-dihydroxy-5-methyl-2H-pyran-2-acetamide and is primarily active against Gram-positive microorganisms.
Japan Antibiotics Research Association