Allophenylnorstatine [APNS; (2S,3S)-3-amino-2-hydroxy-4-phenylbutyric acid], a component of the HIV-1 protease inhibitor kynostatin, has been prepared via a tandem conjugate addition-electrophilic hydroxylation strategy using lithium (S)-(α-methylbenzyl)benzylamide and (+)- (camphorsulphonyl)oxaziridine. The effects of molecular recognition and enolate geometry on the selectivity of the reaction are discussed.