Abstract
Recently, a bisbibenzyl named plagiochin E showing remarkable
antifungal and antitumor activities was isolated from Marchantia polymorpha , a liverwort. The
total synthesis of the proposed structure for plagiochin E and of
two structurally and biosynthetically related bisbibenzyls and comparison
of the NMR data of the synthetic compounds with those of the isolated
bisbibenzyls necessitates a structure revision for plagiochin E.
Exemplarily for this metabolite, the stereostructure was investigated,
by racemate resolution on a chiral Lux Cellulose-1 phase with HPLC-CD
coupling and quantum chemical CD calculations, clearly assigning
the P -configuration for the faster and
the M -configuration to the slower enantiomer.
Key words
plagiochin E - bisbibenzyl - axially chiral
biaryl - total synthesis - natural products - circular
dichroism
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General Procedure
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in MeCN (60 mL) was refluxed for 12 h. The solvent was removed in
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