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We wish to retract this article as we can no longer claim that the observed reactivity for the Suzuki-Miyaura-type coupling of aryl halides and arylboronic acids is attributed to the amine organocatalyst. Efforts from different laboratories-published in the form of Matters Arising articles 1-3 -have pointed to the fact that the reaction is catalyzed by residual palladium impurity contained in the amine. We have performed a series of validation experiments confirming that during the synthesis of the amine, stable palladium complexes are formed, which could not be completely removed by column chromatography. Moreover, the ICP-MS method we used could not completely digest the residual palladium. Such factors led us to misjudge the nature of the catalyst.We are very grateful to the authors of the Matters Arising articles for raising these issues. We sincerely apologize to the scientific community for any confusion arising from our publication. All authors agree with this retraction.

A phytochemical investigation of the ethanolic extracts of the dried roots of Euphorbia nematocypha resulted in the isolation of a new phenylpropanoid, 16-O-caffeoyl-16-hydroxylhexadecanoic acid (1), together with 23 known compounds (2-24). Their structures were elucidated on the basis of spectroscopic data. Compound 1 was first to be isolated as a caffeic acyl long chain alkyl acid from the family Euphorbiaceae. The new isolated phenylpropanoid showed potent cytotoxic activities against the MCF-7 and HeLa cell lines.