合成路线1

The Horner-Emmons condensation of 3,5-dimethoxybenzaldehyde (I) with triethyl phosphonopropionate (II) gives the cinnamate ester (III), which is hydrolyzed, treated with SOCl2 and condensed with the chiral auxiliary acylsultam (IV) to yield the adduct (V). The enantioselective methylation of (V) with Me2CuLi gives compound (VI) as the major diastereomer. Subsequent hydrolysis of (VI) with LiOH furnishes carboxylic acid (VII). The reduction of (VII) with LiAlH4 gives alcohol (VIII). The reaction of (VIII) with Ts-Cl and pyridine affords the tosylate (IX), which is condensed with butylmagnesium bromide (X) by means of Li2CuCl4 in THF to provide the adduct (XI). The demethylation of (XI) with BBr3 in dichloromethane gives the resorcinol derivative (XII), which is condensed with 4-hydroxy-myrtenyl pivalate (XIII) by means of BF3-Et2O to yield the cannabinoid pivalate ester (XIV). Finally, the reductive cleavage of the ester group of (XIV) with LiAlH4 yields the target cannabinoid.