The four-membered heterocyclic ring oxetane has been known in literature for almost a century. 1 It has been found in pharmaceutically important natural products such as paclitaxol, 2 oxetin 3 and oxetanocin 4 although the contribution of the oxetanes to their pharmacological properties is not clear. In 2006, Carreira and co-workers 5 reported that introduction of an oxetane ring into a molecule as an isostere of a gem-dimethyl group could have several ...
