Identification of Tetrahydrocannabinol (THC) Analogs, Including Methyl Ether Derivatives of THC and Hexahydrocannabiphorol, THC Methyl Carbonate and Its Synthetic by‐Product, in Commercially Available Oil Products

As of 2025, the distribution of products claiming to contain so-called semisynthetic cannabinoids has continued. In most cases, the names of tetrahydrocannabinol (THC) analogs contained in these products are labeled; however, the actual components are often unknown. In this study, we identified the compounds in products that claim to contain THC analogs. Gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-photodiode array-mass spectrometry (LC-PDA-MS) were used to analyze six products. Seven compounds were isolated from products via silica gel column chromatography, and their structures were determined by ¹H, ¹³C NMR, and various two-dimensional NMR techniques, including H-H correlation spectroscopy, heteronuclear multiple quantum coherence, heteronuclear multiple-bond correlation, and nuclear Overhauser effect spectroscopy. The compounds detected in products A and B were identified as Δ⁸-THCM and Δ⁹-THCM. From product C, 9(R)-hexahydrocannabiphorol methyl ether (9(R)-HHCPM) was identified. The compounds isolated from product D were identified as 2-allyl-Δ⁸-THC. Δ⁹-THC methyl carbonate and Δ⁸-iso-THC methyl carbonate were isolated and identified from product E. The compounds isolated from product F were identified as 10(S)-Hydroxy-9(R)-HHC. This study is the first report on THC analogs having methylcarbonated hydroxyl groups at the C1 position of THC in commercial products. The newly detected THC analogs are potential health hazards if used in general; there are no toxicity data for any of these compounds. In addition, with their unregulated synthesis and the by-product/residues that might have concerns exist. Thus, there are concerns regarding the distribution of products containing new THC analogs.