The 5-ht1E receptor is one of the least known serotonin receptors. Little has been reported about its pharmacological effects and the physiological role is not known. One of the reasons for this is that no selective agonists or antagonists are known for this receptor. The target molecules in this work are conformationally rigid serotonin analogues, and potential ligands for the 5-ht1E receptor.
A new synthetic route to an intermediate in the synthesis of the target molecules has been developed. The key step in the synthesis of this intermediate is a metal catalysed intramolecular C-H insertion reaction with an indole-á-diazo-â-ketoester and Pd(OAc)2. Different protective groups and synthetic strategies have been tested in the synthesis of this indole-á-diazo-â-ketoester.