When N - acetyl- L -aspartic acid is treated with acetic anhydride, an optically active compound A,

Question:

When N - acetyl- L -aspartic acid is treated with acetic anhydride, an optically active compound A, C6H7NO4, is formed" Tleaffient of A with the amino acid L -alanine yields two separable, isomeric peptide$, B and C, that are both converted into a mixture of l-alanine and r-aspartic acid by acid hydrolysis. Suggest structures for A, B, and C.