The presence of this chiral side chain has proven to be essential for the biological activity of taxol, one of the most promising anticancer agents being investigated. The challenging synthesis of taxol has stimulated interest in the attachment of the C-13 side chain to naturally derived taxanes like baccatin III. It has been proven that the presence of this chiral side chain is essential for the biological activity of paclitaxel. The complex synthesis process of paclitaxel has attracted attention to attaching C-13 side chains to naturally derived taxanes (for example, baccatin III).