Treatment of cis-1,4-diaryl-2,3-epoxy butane with 2,3-dichloro-5,6-dicyano-1,4-benzo-quinone(DDQ) in trifluoroacetic acid(TFA) gave dibenzocycloheptadienes by pinacol rearrangement and intramolecular oxidative couplin...Treatment of cis-1,4-diaryl-2,3-epoxy butane with 2,3-dichloro-5,6-dicyano-1,4-benzo-quinone(DDQ) in trifluoroacetic acid(TFA) gave dibenzocycloheptadienes by pinacol rearrangement and intramolecular oxidative coupling of the aryl groups. Meanwhile, the benzofuran analogues were also formed by the same method. These new lignans have potent CNS inhibitory activities. It has been proven that the method is particularly useful when applied to the substrates in which the ring substituents are electron donating. The structures of these products were identified by the MS, UV, IR, NMR spectra, and elemental and X-ray crystallographic analyses.展开更多
Two new lignans with dibenzocycloheptadiene skelectons have been synthesized by intramolecular nonphenolic oxidative coupling and rearrangement. The structures of these products have been identified by MS, UV, IR and ...Two new lignans with dibenzocycloheptadiene skelectons have been synthesized by intramolecular nonphenolic oxidative coupling and rearrangement. The structures of these products have been identified by MS, UV, IR and NMR spectra.展开更多
文摘Treatment of cis-1,4-diaryl-2,3-epoxy butane with 2,3-dichloro-5,6-dicyano-1,4-benzo-quinone(DDQ) in trifluoroacetic acid(TFA) gave dibenzocycloheptadienes by pinacol rearrangement and intramolecular oxidative coupling of the aryl groups. Meanwhile, the benzofuran analogues were also formed by the same method. These new lignans have potent CNS inhibitory activities. It has been proven that the method is particularly useful when applied to the substrates in which the ring substituents are electron donating. The structures of these products were identified by the MS, UV, IR, NMR spectra, and elemental and X-ray crystallographic analyses.
文摘Two new lignans with dibenzocycloheptadiene skelectons have been synthesized by intramolecular nonphenolic oxidative coupling and rearrangement. The structures of these products have been identified by MS, UV, IR and NMR spectra.