Gualamycin, a novel acaricide produced by Streptomyces sp. NK11687. II: Structural elucidation

A novel acaricide, gualamycin was isolated from the culture broth of Streptomyces sp. NK11687. The structure of gualamycin was determined to be (2R, 3S, 4S)-2-O-[4-O-(2-amino-2-deoxy-β-D-gulopyranosyl)-a-D-galactopyranosyl]-2, 3, 4-trihydroxy-4-[(2S, 3S, 4S, 5S)-3, 4-dihydroxy-5-hydroxymethylpyrrolidin-2-yl] butanoic acid by FAB-MS, 1H and 13C NMR, COSY, HMQC, HMBC, IR, X-ray crystallographic analyses and synthetic studies.