Inhibitors of dihydrofolate reductase: Design, synthesis and antimicrobial activities of 2,4-diamino-6-methyl-5-ethynylpyrimidines

Novel 2,4-diamino-6-methyl-5-ethynylpyrimidines were prepared via palladium catalyzed coupling of 2,4-diamino-5-iodo-6-methyl-pyrimidine with terminal acetylenes. The compounds were inhibitors of dihydrofolate reductase and showed in vitro activity against several species of opportunistic fungi and the protozoan Toxoplasma gondii.