New Chiral Aminoamidoximes: Syntheses and Investigation of Heterocyclic Compounds

New chiral aminoamidoximes were prepared from (L)-proline, (L)-alanine, and (L)-isoleucine by treatment of the corresponding aminonitriles with hydroxylamine in the presence of triethylamine. The intramolecular cyclization with α-bromoacid chlorides and aldehydes was investigated to give new 1,2,4-oxadiazin-6-ones and 1,2,4-oxadiazoles, respectively. These compounds were likely to undergo an intermolecular cyclization through oxygen and nitrogen. However, intramolecular cyclization through two nitrogens did not occur even after changing reaction conditions.