LSD-Pip
LSD-Pip is a compound from the ergoline family, related to LSD but with the "N,N"-diethyl substitution replaced by a piperidine group. It is more potent than the corresponding pyrrolidine and morpholine analogues (LPD-824 and LSM-775 respectively), but is still several times less potent than LSD as a 5-HT agonist. Early studies suggested this compound to be inactive as a psychedelic in humans, though this does not seem to have been confirmed by any more recent work.