l-v-triazolo[d]pyrimidine4
was aroused by the report of Kidder, Dewey, Parks, and Woodside: that this compound caused definite inhibition of growth in mice of a transplantable mammary adenocarcinoma, Eo77 1. A prior article by Kidder and Dewey' had shown that this substance was a potent antagonist of guanine in the metabolism of the ciliate, Tetrahymena geleii. Because of the possible value of the drug in the therapy of human tumors, preliminary toxicity studies were done on rats and dogs in the Department of Pharmacology,3 and the compound was then administered in eight cases of radiationresistant cancer. The purpose of this preliminary note is to describe certain toxic reactions resulting from the use of the drug.
Since little is known of the absorption of the compound when given by mouth, and because toxicity studies had all been based on parenteral dosage, it was decided that the drug should be given intravenously. In order to produce a solution that could be administered in such fashion, an equimolar quantity of sodihm hydroxide was added to 5-amino-7-hydroxy-1 -v-triazolo [d]pyrimidinet and the latter made up in concentration of 5 mg. per cc. in physiological saline solution. It was usually injected in daily doses of 200 mg. each.
The drug was also available in capsules for oral use.