A NEW STEREOSELECTIVE ROUTE TO PRODUCE TRIS-O-SUBSTITUTED-(E)-1-(3,5-DIHYDROXYPHENYL)-2-(4- HYDROXYPHENYL)ETHENE, AN INTERMEDIATE IN THE SYNTHESIS OF TRANS-RESVERATROL

摘要

The present invention relates to a new stereoselective method for the preparation of tris-O-substituted-(E)-1-(3,5-dihydroxyphenyl)-2-(4-hydroxyphenyl) ethene of the formula (I) which is a key intermediate in the synthesis of trans-resveratrol (I-, R1=R2=R3=H). The invention also provides a method for the exclusive synthesis of trans-isomer of compounds of formula (I) without any contamination of cis-isomer.