The reaction of aldehydes and ketones, including aliph. and arom. ones, with amides of alpha -isocyano-beta -phenylpropionic acid in toluene in the presence of lithium bromide gives 2,4,5-trisubstituted oxazoles in good to excellent yield. Protected chiral alpha -amino aldehydes participate in this reaction to give, after hydrolysis of the oxazoles, norstatine-contg. peptides in good overall yield. The nucleophilic addn. of isonitriles to N,N-dibenzylphenylalanal is investigated for the first time and is found to be stereoselective leading predominantly to the anti-adduct (dr = 9/1). On the other hand, the reaction between the N-Boc phenylalanal and isonitrile is non-stereoselective. [on SciFinder (R)]