Lysergic acid pyrrolinide, also known as dihydropyrrol lysergamide or as N-(2,5-dihydro-1H-pyrrolyl)lysergamide, is a serotonin receptor modulator and possible psychedelic drug of the lysergamide family related to lysergic acid diethylamide (LSD). It is the analogue of LSD in which the N,N-diethylamide moiety has been cyclized into an N-pyrroline ring. The drug is similar in chemical structure to lysergic acid pyrrolidide (LPD-824).
It has 4.1% of the antiserotonergic activity of LSD in the isolated rat uterus and its hallucinogenic activity in humans has not been reported. Unlike the related compounds LPD-824 and LSM-775 (lysergic acid morpholide), lysergic acid pyrrolinide does not appear to have been assessed in humans. Like LPD-824, the drug has greater hypotensive effects than LSD in animals.
Lysergic acid pyrrolinide was first described in the scientific literature by Albert Hofmann and colleagues by 1958.