Bacimethrin, 2-methoxy-4-amino-5-hydroxymethyl pyrimidine, was isolated from the culture broth of a strain of Bacillus megaterium^1,2). The antibacterial activity was reversed by vitamin B¹ or B⁶. The activity against experimental infections of Staphylococcus aureus and Salmonella enteritidis was examined in mice. The effects on neoplasmic growth and on viral multiplication were also investigated. The results are presented in this publication.

Monazomycin, another new antibiotic, was obtained from a culture beer of Streptomyces mashiuensis. It had toxicity to mice and inhibited growth of Bacilli and Mycobacteria. The activity against transplantable mouse tumors was studied and the results are described in this paper.