摘要:
Pictet-Spengler reactions were carried out between 3-carbomethoxy-2-(formylmethyl)-3-sulfolene and tryptamines. Without isolation, the products were converted with complete stereoselectivity into apoyohimbine derivatives, via sulfur dioxide extrusion followed by intramolecular Diels-Alder cyclisation. (C) 1997 Published by Elsevier Science Ltd.