AN EXPEDITIOUS ASYMMETRIC-SYNTHESIS OF ALLOPHENYLNORSTATINE

Allophenylnorstatine [APNS; (2S,3S)-3-amino-2-hydroxy-4-phenylbutanoic acid], a novel amino acid found in the kynostatin class of HIV-1 prot ease inhibitors, has been prepared in 39% overall yield via a tandem c onjugate addition-electrophilic hydroxylation protocol using lithium ( S)-(alpha-methylbenzyl)benzylamide and (+)-(camphorsulfonyl)oxaziridin e. An unprecedented level of molecular recognition between a homochira l beta-amino enolate and a homochiral oxaziridine is identified and th e importance of enolate geometry upon hydroxylation stereoselectivity is also addressed.