DDQ在五味子素代谢产物合成中的应用

Use of DDQ in the Synthesis of An Analogue of Schzandrin

2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)是一种常用脱氢氧化剂。K.V.Rao 等发现当它在三氟醋酸(TFA)介质中作用于1。

The erythro-component of 4,5-di(3',4',5',-trimeth oxybenzyl)-4,5-dimethy1-2ethoxy-1,3-dioxolan(2) underwent intramolecular non-phenolic oxidative coupling in trifluoroacetic acid to give 1,2,3,10,11,12-hexamethoxy-6,7-dihydroxy-cis-6,7-dimethyl dibenzocyclooctadiene(4),which was found to be one of the metabolites of Schizandrin.Meanwhile,the threo-component of compound(2) gave 3',4',5',-trimethoxybenzo [c] -6-(3″,4″,5″-tri-methoxybenzyl)-5,6-dimethyl-7,8-dioxabicyclo [3.2.1] heptane (5).Under the same condi-tion,1,4-di(3',4',5',-trimethoxy) pheny1-2,3-dimethy1-2,3-butanediol (1) gava Di [3H-furo [b] -2-spiro-1'-(2',5',-cyclohexadiene-3',5'-dimethoxy-4'-one)-4-methyl](3) whichcorresponded to the threo-component of 1,no trace of 4 was detected.The reaction mecha-nism was discussed.