The effect of 5-alkyl modification on the biological activity of pyrrolo[2,3-d]pyrimidine containing classical and nonclassical antifolates as inhibitors of dihydrofolate reductase and as antitumor and/or antiopportunistic infection agents.

The effect of 5-alkyl modification on the biological activity of pyrrolo[2,3-d]pyrimidine containing classical and nonclassical antifolates as inhibitors of dihydrofolate reductase and as antitumor and/or antiopportunistic infection agents.