Synthesis of Cyclobutane Serine Analogues

摘要

In this paper,we describe a thermal [2 + 2] cycloaddition involving 2-acylaminoacrylates as electron-poor acceptor alkenes,a reaction that involves a Michael-Dieckmann-type process.The reaction gives rise to a new substituted cyclobutane skeleton that can be transformed into amino acid derivatives.For example,a number of transformations were carried out to give the two pairs of stereoisomers of the 2-hydroxycyclobutane-a-amino acid serine analogue(c_4Ser);compounds 22 and 23.This synthesis covers a gap in knowledge in the broad field of restricted amino acids.