Cannabinoid hydroxylation sites

A fourth important pharmacophoric element was established for the non-classical cannabinoid series in the form of a southern aliphatic hydroxyl group. Addition of this group to (192) resulted in the high-affinity CBi and CB2 receptor full agonist CP 55,940 (193) [129, 133], the tritiated form of which was used to first demonstrate specific cannabinoid binding sites in brain tissue [134]. Its enantiomer, CP 56,667 (194) has lower affinity for the CBi receptor (Table 6.17). 

Figure 1. Hydroxylation sites of cannabinoids observed in vitro or in vivo...

The application of GLC-MS techniques to the ill vitro and ill vivo metabolism of A9-THC (8) laid the groundwork for the quantitative analysis of other cannabinoid metabolites. The sites of metabolic hydroxylation for many cannabinoids are shown in Figure 1. 

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