Total synthesis of the coccinellid alkaloid (-)-adalinine and the assignment of its absolute configuration

The first asymmetric total synthesis of a new coccinellid alkaloid (-)-adalinine has been achieved, based on the construction of a 2-piperidone framework with an asymmetric quaternary center at the C-6 position, which was performed by Lewis acid-induced allylation of the cyclic N-acyl-N,O-acetal incorporating the chiral aminophenol auxiliary. This synthesis allowed the absolute stereostructure of natural (-)-adalinine to be assigned as R. (C) 1999 Elsevier Science Ltd. All rights reserved.