Synthesis of (±)-Esermethole via an Intramolecular Carbamoylketene-Alkene [2+2] Cycloaddition
摘要:
A synthesis of (+/-)-esermethole (2), a synthetic precursor of physostigmine (1), has been accomplished by using an intramolecular carbamoylketene-alkene [2+2] cycloaddition followed by nitrone-mediated regioselective ring expansion for the construction of the basic carbon framework of 2 as the key steps.