JWH-138


JWH-138 is a synthetic cannabinoid first synthesized by Roger Adams and later studied by John W. Huffman, with a Ki of 8.5nM at the CB1 cannabinoid receptor.
Δ9-THC-Octyl and its hydrogenated analog HHC-Octyl was synthesized and studied by Roger Adams as early as 1942, and should not be confused with the Δ8 analog.

Isomers

The Δ36a isomer was synthesised in 1941, but was found to be slightly less active than Δ3-THC itself. The alternate isomer Δ9-THC-C8 has also been synthesised,.
Tetrahydrocannabioctyl is sometimes referred to as THC-Octyl or THC-O, which may cause confusion with THC-O-acetate which is commonly known as THC-O on packaging for grey market vaping liquids sold for use in humans. Both Δ8 and Δ9 -THC have been sold as designer drugs, first identified in Denmark in August 2024.

Legality

Both the Δ8 and Δ9 isomers are included within the definition of an "intoxicating cannabinoid" in Colorado under the name tetrahydrocannabioctyl, but it is unclear if it has been identified as a natural product.