Abstract: This invention relates to novel biologically active polyene oxazoles, their pharmaceutically acceptable salts and derivatives, and to methods of obtaining them. One method for obtaining the compounds is by cultivation of Streptomyces sparsogenes NRRL 2940 or a mutant or variant thereof.

Abstract: Polyene oxazoles of the following formula wherein R3 is selected from H and methyl, are disclosed. Such compounds, and pharmaceutically acceptable salts thereof, may be used in the inhibition of tumor cell growth. The polyene oxazoles and their pharmaceutically acceptable salts may be formulated as pharmaceutical compositions with pharmaceutically acceptable carriers for use in the inhibition of tumor cells. The polyene oxazoles may be obtained from strains of Streptomyces sparsogenes, such as strain 022 having deposit number IDAC 270504-04.

Abstract: Novel polyene oxazole compounds of Formula I: are useful as cytotoxic agents. The polyene oxazoles may be made by fermentation of Streptomyces sparsogenes and optional post-biosynthesis chemical modification thereof.