Ring substitution influences oxidative cyclisation and reactive metabolite formation of nordihydroguaiaretic acid analogues
作者:Isaac Asiamah、Heather L. Hodgson、Katherine Maloney、Kevin J.H. Allen、Ed S. Krol
DOI:10.1016/j.bmc.2015.09.039
日期:2015.11
group of analogues the catechols were less stable than phenols, a single catechol-substituted ring is insufficient to form a dibenzocyclooctadiene lignan, and only compounds possessing a di-catechol could form dibenzocyclooctadienes. This suggests that quinone formation may not be necessary for cyclisation to occur and the intramolecular cyclisation likely involves a radical-mediated rather than an electrophilic
An efficient approach for the synthesis of several types of lignans (dibenzylbutanediols, dibenzylbutanes, substituted tetrahydrofurans, aryldihydronaphthalenes, arylnaphthalenes, and aryltetralins) was developed. The regioselectiveoxidative coupling of ethyl ferulate was used as the key step.
The antioxidant activity of butane-type lignans was evaluated. Secoisolariciresinol (SECO) and dihydroguaiaretic acid (DGA) showed higher radical scavenging activity than that of 7,7′-dioxodihydroguaiaretic acid (ODGA). SECO and DGA inhibited the oxidation of unsaturated fatty acid. Both enantiomers of DGA were also lipoxygenase inhibitors, but neither enantiomer of SECO inhibited the lipoxygenase activity.