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Acids. -The synthesis of resveratrol (XIV) by Perkins condensation of dimethoxybenzaldehyde (I) with anisylacetic acid (II) is re-investigated, concerning isomerization of the obtained diarylacrylic acid (III) during decarboxylation and deprotection steps. Several improvements enable the formation of resveratrol in 85% yield as pure trans-isomer, involving Perkins condensation of the corresponding isopropoxy-protected analogues (VIa) and (VIIa), decarboxylation with copper chromite, controlled isomerization of cis-to trans-stilbene derivative (XV) and deprotection. The method is successfully applied to a variety of polyhydroxylated stilbene derivatives such as (VIII), (IX) and (X)/(XI). -(SOLLADIE*, G.; PASTUREL-JACOPE, Y.; MAIGNAN, J.; Tetrahedron 59 (2003) 18, 3315-3321; Lab. Stereochim., CNRS, Univ. Louis Pasteur, F-67087 Strasbourg, Fr.; Eng.) -Mischke 33-105