cis-Delta-9-Tetrahydrocannabinol ((-)-cis-Δ9-THC) is an isomer of tetrahydrocannabinol found in the Cannabis plant but in lower quantities than the more well-known trans isomer. It has similar psychoactive effects to trans-Δ9-THC in tests on mice, but with only around 1/5th the potency. The equivalent Δ8 isomer is also known as a synthetic compound, but has not been isolated from Cannabis plant material. All four cis/trans isomers are known, though only the (6aR,10aR) and (6aS,10aR) enantiomers are psychoactive, while the others retain activity at targets such as GPR18 and GPR55.[1][2][3][4][5][6][7][8]
A diagram showing the isomers of delta-9-THC with carbon number indicated according to dibenzopyran numbering scheme. Cahn-Ingold-Prelog R/S designation is indicated. Please note that "synthetic" here refers to macroscopic quantities, and that these stereoisomers that are labeled as synthetic may be present in C. sativa or other organisms at trace levels compared to trans-(-)-d9-THC
^Ballerini E, Minuti L, Piermatti O, Pizzo F (June 2009). "High pressure Diels-Alder approach to hydroxy-substituted 6a-cyano-tetrahydro-6H-benzo[c]chromen-6-ones: a route to delta(6)-cis-cannabidiol". The Journal of Organic Chemistry. 74 (11): 4311–4317. doi:10.1021/jo9005365. PMID19402693.
^Minuti L, Ballerini E (July 2011). "High-pressure access to the Δ9-cis- and Δ9-trans-tetrahydrocannabinols family". The Journal of Organic Chemistry. 76 (13): 5392–5403. doi:10.1021/jo200796b. PMID21563759.
^Schafroth MA, Zuccarello G, Krautwald S, Sarlah D, Carreira EM (December 2014). "Stereodivergent total synthesis of Δ9-tetrahydrocannabinols". Angewandte Chemie. 53 (50): 13898–13901. doi:10.1002/anie.201408380. PMID25303495.
