Synonyms: 4,6(1H,5H)-Pyrimidinedione, 5-ethyldihydro-5-(1-methylbutyl)-2-thioxo-, monosodium salt, (R)-;4,6(1H,5H)-Pyrimidinedione, 5-ethyldihydro-5-[(1R)-1-methylbutyl]-2-thioxo-, monosodium salt (9CI);R-(+)-Thiopental sodium;(+)-5-Ethyl-5-[(R)-1-methylbutyl]-2-sodiothio-4,6(1H,5H)-pyrimidinedione