Abstract：
:Vitamin E is an essential nutrient of still increasing economic importance. Vitamin E derivatives include many nonracemic chiral compounds whose chirooptical characterization is scarcely described in the literature. We report the CD spectra of delta-tocopherol and its unsaturated analog delta-tocotrienol. TDDFT calculations demonstrate that the weak CD of delta-tocopherol is determined by the helicity of dihydropyrane ring. In addition, the moderate CD of delta-tocotrienol is due to the exciton interaction between the aromatic ring and the closest alkene group. Direct exciton-coupled CD calculations on structures generated by two different conformational sampling approaches reveal that, although such exciton coupling is expected to be weak, it is sufficient to explain the spectral differences between tocopherol and tocotrienol.
journal_name
Chiralityjournal_title
Chiralityauthors
Mazzini F,Pescitelli G,Di Bari L,Netscher T,Salvadori Pdoi
10.1002/chir.20591subject
Has Abstractpub_date
2009-01-01 00:00:00pages
35-43issue
1eissn
0899-0042issn
1520-636Xjournal_volume
21pub_type
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