Question

The cancer drug paclitaxel (trade name Taxol), is a complex molecule with 11 stereocenters. Taxol The biologically active isomer has a specific handedness at each of these stereocenters. Suppose a synthesis of this molecule is performed without regard to the stereochemistry so that the product is produced in a racemic mixture in which each diastereomer is present in equal amounts. What fraction of the product is present in the biologically active form?

NH Οι..

Answer 1

Normally, all compounds have 1 active form that is dependent in all of the structure. In this case that means, that only 1 of the diastomers have the active form, to know what portion of the mixture will have it me must know all the possibilities. Having two sterocenters will allow 4 differences compositions , from there is derived the formula 2ⁿ, where n is equal to the sterocenters. In this case is 2¹¹= 2048 possibilities. Given that the mixture is equal parts of every single one of them, then 1/2048 of the mixture is the active form of paclitaxel .