1. A method for synthesizing Jarrow Pterostilbene
1. Preparation of stilbene intermediates
(1) Preparation of intermediate 3,5-dimethoxybenzyl bromide, respectively, take 3,5-dimethoxybenzyl alcohol and HBr solution with a concentration of more than 40%, and feed 3,5-dimethoxybenzyl alcohol and HBr solution The amount in g:ml is 1:5～10, and the reaction is carried out at 50～100℃ for 10～28h to obtain 3,5-dimethoxybenzyl bromide; the preferred concentration is 48%;
(2) Preparation of intermediate 4, ?0? Tetrahydropyranbenzaldehyde 1,4? Dihydropyran and p-hydroxybenzaldehyde were dissolved in a solvent and reacted at 20 ~ 45 ℃ for 1 ~ 5h, after the reaction was completed, a base was added The liquid is processed, and the organic phase is reclaimed to obtain 4,0 tetrahydropyran benzaldehyde; acid catalyst should be added during the reaction, and wherein the feeding amount of 3,5 dimethoxybenzyl bromide and p-hydroxybenzaldehyde solution is calculated as mol:mol. 1:1～2.5; the solvent is THF, dichloromethane or dichloroethane;
2. Preparation of 3,5 dihydrocarbyl 4, O tetrahydropyran stilbene The prepared 3,5 dimethoxybenzyl bromide and trimethyl phosphite are refluxed to obtain 3,5 dimethoxybenzyl phosphine Dimethyl acid, and then mixed with 4,0 tetrahydropyran benzaldehyde in the reaction solvent, and reacted at 0℃～40℃ for 2h～10h to obtain 3,5dimethoxy 4,O tetrahydropyridine Stilbene; Described reaction solvent is DMF or THF;
3. Preparation of Jarrow Pterostilbene Put the prepared 3,5? Methoxy 4, O tetrahydropyran stilbene in the reaction solvent, then add an acid catalyst, and deprotect the protective group under the catalysis of the acid catalyst to obtain the product Pterostilbene, After the reaction is completed, the solvent is recovered under reduced pressure, and the finished pterostilbene is obtained after the treatment, and the reaction temperature is 25°C to 80°C; the reaction solvent is methanol or ethanol, and the reaction solvent is mixed with 3,5 methoxy 4,0 tetrahydropyran. The feeding amount of stilbene is 5-10:1 in g:ml, and the reaction time is 1h-6h.
2. Intermediate (E)-3,5-dimethoxy-4 was prepared by Grignard reaction of 3,5-dimethoxybenzyl chloride and p-benzyloxybenzaldehyde and catalytic dehydration of solid acid catalyst NaHSO4.SiO2 -Benzyloxy stilbene, and then debenzylated by Pd/Al-MCM-41 mesoporous zeolite catalyzed hydrogenation to obtain Jarrow Pterostilbene.