Cannabichromene

Cannabinoids including cannabidiol (CBD), cannabigerol (CBG), cannabicitran (CBT), cannabinol (CBN), cannabichromene (CBC), cannabigerolic acid (CBGA), cannabidiolic acid (CBDA), and cannabidivarin (CBDV) delta-8-tetrahydrocannabinol (Δ8-THC) were purchased from Cayman Chemical (Ann Arbor, MI, USA; see their chemical structures in Figure 1).
Chemicals including the erastin, etoposide, and lactate dehydrogenase (LDH) assay kit were purchased from Cayman Chemicals. The derivatives of CBD (1–56) were chemically synthesized by our laboratory with a protocol previously reported [10 (link)]. Phosphate-buffered saline (PBS), dimethyl sulfoxide (DMSO), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), 2′,7′-dichlorofluorescin diacetate fluorescent probe (DCF-DA), and crystal violet were purchased from Sigma-Aldrich, Co. (St. Louis, MO, USA). Paraformaldehyde and the Alexa Fluor^TM 488 Annexin V/Dead cell apoptosis kit were purchased from Thermo Fisher Scientific (Waltham, MA, USA). The Liperfluo and FerroOrange assay kits were obtained from Dojindo Lab (Kumamoto, Japan).

Six of the seven cannabinoid analytes [∆⁹-THC, cannabinol (CBN), cannabigerol (CBG), cannabigerolic acid (CBGA), ∆⁹-tetrahydrocannabinolic acid A (∆⁹-THCA), and ∆⁹-tetrahydrocannabivarin (∆⁹-THCV)] and the internal standard (IS; ∆⁹-THC-D₃) were obtained as certified reference materials (CRMs) manufactured by Cerilliant (Round Rock, TX). Cannabichromene (CBC) was obtained as a CRM from Cayman Chemical (Ann Arbor, MI). When not in use, concentrated stock solutions of these agents and working solutions made therefrom were stored at –20 °C.
Acetonitrile, formic acid, methanol, and n-hexane were purchased from Thermo Fisher Scientific and were of LC/MS grade. Ethyl acetate (Acros Organics) was purchased from Thermo Fisher Scientific and was of spectroscopy grade (> 99.5%). High purity water (18.2 MΩ) required for preparing the mobile phase and for sample extraction was produced using an EMD Millipore Simplicity water purification system. When not in use, these agents were stored at room temperature (20–25 °C). Nitrogen (N₂), supplied as a cryogenic liquid in a 230L dewar at a purity of 99.998%, or as compressed nitrogen gas at a purity of 99.999% in T-type cylinders, was obtained from Praxair (Danbury, CT).

Gemcitabine, cisplatin, Δ⁹-tetrahydrocannabinol, cannabidiol, orientin, quercetin, silymarin, vitexin, isovitexin, and luteolin were obtained from Millipore-Sigma (Oakville ON, CA). Cannflavin A, kaempferol, apigenin, cannabichromene, and cannabivarin were obtained from Cayman Chemical (Ann Arbour MI, USA).