7-Hydroxyropinirole (developmental code name SK&F-89124 or SKF-89124) is a dopamine receptor agonist and active metabolite of the antiparkinsonian agent ropinirole (SK&F-101468). It is a major metabolite of ropinirole in rats and dogs but a minor metabolite in mice, monkeys, and humans. In humans, 7-hydroxyropinirole accounts for less than 5% of a dose of ropinirole. Its involvement in ropinirole's effects in humans is unknown. The drug is described as a highly potent and highly selective dopamine D2-like receptor agonist. It has been reported to be 30-fold more potent than ropinirole as a dopamine D2 receptor agonist in vitro. However, ropinirole and 7-hydroxyropinirole were equipotent in terms of antiparkinsonian activity in rodents in vivo. 7-Hydroxyropinirole is said to be rapidly glucuronidated in humans. In addition, 7-hydroxyropinirole has reduced capacity to cross the blood–brain barrier than ropinirole. This is due to its hydroxyl group, which increases it polarity and reduces its lipophilicity. The log P of ropinirole is 2.46, whereas that of 7-hydroxyropinirole is 2.17. 7-Hydroxyropinirole was first described in the scientific literature by 1983. Subsequently, ropinirole was described in 1985.
See also Partial ergoline 14-Hydroxy-LSD Lergotrile
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