4'-Hydroxylated derivatives as urinary metabolites of two barbiturates.

4'-Hydroxybutobarbitone and 4'-hydroxypentobarbitone have been synthesized. These 4'-hydroxy derivatives have been quantified in the urine of volunteers following single doses of butobarbitone, and single and multiple doses of pentobarbitone. The corresponding aldehydes have also been synthesized, and shown to be excreted in minor quantities. The excretion of an ingested dose of 4'-hydroxybutobarbitone, and its oxidation products, has also been followed over 24 h.