Conformationally restricted paclitaxel analogues: macrocyclic mimics of the "hydrophobic collapse" conformation

Conformationally restricted macrocyclic analogues of paclitaxel were prepared, by connecting the 3'-phenyl group and the 2-benzoate moiety with two-atom tethers to mimic the "hydrophobic collapse" paclitaxel conformation. The analogues did not show activity in a tubulin assembly assay.