Stereochemistry of tetrahydrofurofuran derivatives—circular dichroism and absolute conformation

摘要: Abstract The CD spectra of 12 different lignans the sesamin type were recorded. In several cases can be interpreted quantitatively in terms a coupled oscillator model allowing to deduce absolute configurations and conformations. To this end computer programs used which reflect successive steps procedure: (i) curve fit for bands 1Bb region giving reliable values band splittings experimental couplets; (ii) search possible solutions simulate these splittings, geometrical parameters transition moments; (iii) PPP-SCF-MO-CI calculations UV determine orientation moments within aromatic moieties; (iv) COORD program link derived from with stereochemistry total 1,4-diaryl-tetrahydrofurofuran molecule.