Natural products of Thailand high Δ ¹ -THC-strain Cannabis. The bibenzyl-spiran-dihydrophenanthrene group: relations with cannabinoids and canniflavones

Since non-cannabinoids may influence the pharmacological profile of Cannabis-leaf drug, a detailed examination of the acidic fraction from leaf extractive has been made. Twelve non-cannabinoids have been isolated crystalline from a single high Δ1-THC-strain of Thailand Cannabis grown in Nottingham under controlled conditions: nine of the compounds were not previously known as natural products and their structures have been determined. The extractives comprise three bibenzyls, six spirans, two 9,10-dihydrophenanthrenes, and two prenylated flavones.The bibenzyls, spirans, and dihydrophenanthrenes may be linked together in a biogenetic scheme in which one-electron oxidation and reductive processes play important parts: the scheme is particularly supported by the discovery of a new spiran, cannabispiradienone, which holds a key position and undergoes a dienone–phenol rearrangement to give one of the new dihydrophenanthrenes. Relations between bibenzyl, cannabinoid, and flavone pathways are briefly considered.