Carmoxirole


Carmoxirole is a dopamine D2 receptor agonist which was developed as a potential antihypertensive and heart failure medication but was never marketed. It is taken orally.

Pharmacology

Carmoxirole is a potent, selective, and peripherally restricted partial agonist of the dopamine D2 receptor. It showed about 1,000-fold higher affinity for the dopamine D2 receptor over the dopamine D1 receptor. Carmoxirole also showed some affinity for the serotonin 5-HT1A receptor and for the α2-adrenergic receptor, whereas affinity for other receptors like the serotonin 5-HT2, α1-adrenergic, and β-adrenergic receptors was negligible.
The drug has been found to reverse hyperprolactinemia induced by the dopamine D2 receptor antagonist amisulpride without producing central effects in rats. It has also been found to reduce circulating norepinephrine levels by 55% in people with severe heart failure, an action thought to be mediated by its dopamine D2 receptor agonism in the periphery. This depression in norepinephrine levels was accompanied by improvements in cardiovascular parameters.

Chemistry

Carmoxirole is an indole derivative and shows similarities in its chemical structure to tryptamines and pertines like oxypertine but has an elongated alkyl side chain and hence does not belong to these groups itself.

History

Carmoxirole was first described in the scientific literature by 1988. It is based on the indolyl-3-butylamine framework, a class of dopamine receptor agonists.