PYROSTATIN-A AND PYROSTATIN-B, NEW INHIBITORS OF N-ACETYL-BETA-D-GLUCOSAMINIDASE, PRODUCED BY STREPTOMYCES SP SA-3501

Pyrostatins A and B, new inhibitors of N-acetyl-beta-D-glucosaminidase (GlcNAc-ase), have be en purified from the culture broth of Streptomy ces sp. SA-3501 isolated from a marine environment. They were purified by chromatography on Dowex 50W silica gel and Capcell Pak C-18(HPLC) followed treatment with active carbon and then isolated as white powde rs. The structures of pyrostatins A and B were determined by NMR studi es to be 4-hydroxy-2-imino-1-methylpyrrolidine-5-carboxylic acid and 2 -imino-1-methylpyrrolidine-5-carboxylic acid, respectively. They were competitive with the substrate, and the inhibition constants(K-i) of p yrostatins A and B were 1.7 x 10(-6) M and 2.0 x 10(-6) M respectively .