11-Hydroxy-Δ8-THC
11-Hydroxy-Δ8-tetrahydrocannabinol is an active metabolite of Δ8-THC, a psychoactive cannabinoid found in small amounts in Cannabis. It is an isomer of 11-OH-Δ9-THC, and is produced via the same metabolic pathway. It was the first cannabinoid metabolite discovered in 1970.
It retains psychoactive effects in animal studies with higher potency than Δ8-THC but lower potency than 11-OH-Δ9-THC. With widespread legal use of semi-synthetic Δ8-THC in certain jurisdictions where Δ9-THC remains illegal, 11-OH-Δ8-THC is now an important metabolite for distinguishing between use of hemp-derived Δ8-THC and natural Δ9-THC.