9,10-Dihydro-LSD
9,10-Dihydro-LSD, or 9,10-DH-LSD, also known simply as dihydro-LSD (DH-LSD) or as 9,10-dihydrolysergic acid diethylamide, is a non-hallucinogenic serotonin receptor modulator of the lysergamide family related to lysergic acid diethylamide (LSD). It is the analogue of LSD in which the 9,10- double bond in the D ring of the ergoline ring system has been hydrogenated.