Fig. 2

Biosynthesis of cannabinoids. a Proposed cannabinoid biosynthetic pathway for Δ⁹-tetrahydrocannabinol (Δ⁹-THC), cannabidiol (CBD), and cannabichromene (CBC) including by-product formation (pentyl diacetic lactone (PDAL), hexanoyl triacetic acid lactone (HTAL), and olivetol shown in the dotted box) and highlighting the chemical conversion of CBD into THC, long thought to be the source of THC, but this conversion does not occur in vivo. b Synthesis of geranyl pyrophosphate (GPP) from dimethylallyl pyrophosphate (DMAPP) and isopentenyl pyrophosphate (IPP) catalyzed by geranyl pyrophosphate synthase