1F-LSD

1F-LSD

Clinical data
Other names	1-(Furan-2-carbonyl)-LSD; 1-(2-Furoyl)-LSD; SYN-L-005; N,N-Diethyl-1-(furan-2-carbonyl)-6-methyl-9,10-didehydroergoline-8β-carboxamide
Routes of administration	Oral
Drug class	Serotonin receptor agonist; Serotonin 5-HT2A receptor agonist; Serotonergic psychedelic; Hallucinogen
ATC code	None
Identifiers
IUPAC name (6aR,9R)-N,N-diethyl-4-(furan-2-carbonyl)-7-methyl-6,6a,8,9-tetrahydroindolo[4,3-fg]quinoline-9-carboxamide
PubChem CID	170763729
Chemical and physical data
Formula	C25H27N3O3
Molar mass	417.509 g·mol−1
3D model (JSmol)	Interactive image
SMILES CCN(CC)C(=O)[C@H]1CN([C@@H]2CC3=CN(C4=CC=CC(=C34)C2=C1)C(=O)C5=CC=CO5)C
InChI InChI=1S/C25H27N3O3/c1-4-27(5-2)24(29)17-12-19-18-8-6-9-20-23(18)16(13-21(19)26(3)14-17)15-28(20)25(30)22-10-7-11-31-22/h6-12,15,17,21H,4-5,13-14H2,1-3H3/t17-,21-/m1/s1 Key:VHDXVHVDSPZVCI-DYESRHJHSA-N

1F-LSD, also known as 1-(furan-2-carbonyl)-LSD, 1-(2-furoyl)-LSD, or SYN-L-005, is a psychedelic drug of the lysergamide family related to lysergic acid diethylamide (LSD).^[1][2] It is thought to act as a prodrug of LSD.^[1][2] The drug interacts with serotonin receptors, including the serotonin 5-HT_2A receptor, and produces the head-twitch response in rodents, with about 3-fold lower potency than LSD.^[1] It hydrolyzes into LSD in rodents.^[1] 1F-LSD was patented in 2024^[2] and was first described in the scientific literature in 2025.^[1] It has been encountered as a novel designer drug in Germany and Japan.^[1]