“Intraperitoneal injection of 5-azaorotate (0.3 µmole/gm) into mice caused an 80 per cent inhibition of the utilization of orotic acid but did not affect the incorporation of uridine into the liver.”
“The pyrimidine analogs, 5-azaorotic acid (6 × 10-7 m) and 5-azauracil (2 × 10-4 m), caused approximately 50 per cent inhibition of the metabolism of orotic acid by cell-free extracts from mouse liver or L5178Y leukemia cells.”