Phaclofen, or phosphonobaclofen, is a selective
antagonist
An antagonist is a character in a story who is presented as the chief foe of the protagonist.
Etymology
The English word antagonist comes from the Greek ἀνταγωνιστής – ''antagonistēs'', "opponent, competitor, villain, enemy, riv ...
for the
GABAB receptor. It was the first selective GABA
B antagonist discovered, but its utility was limited by the fact that it does not cross the blood brain barrier.
References
GABAB receptor antagonists
Phosphonic acids
Chlorobenzenes
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