In the course of our continuing research on phytotoxic compounds from Scolecotrichum graminis Fuckel, which causes a leaf streak disease of orchardgrass, we have reported the isolation of (+)-isocercosporin.1) Here are described the isolation and structural elucidation by the synthesis of novel acetamide compounds 1, 2a and 2b from the same fungus, although these compounds have no significant activity. The isolation procedure for 1, 2a and 2b is described in the experimental section.