Gly-Ala có công thức là A. H2N–CH(CH3)–CO–NH–CH2–COOH. B. H2N–CH2–CO–NH–CH(CH3)–COOH.

H₂N–CH(CH₃)–CO–NH–CH₂–COOH.

H₂N–CH₂–CO–NH–CH(CH₃)–COOH.

H₂N–CH₂–CH(CH₃)–CO–COOH.

H₂N–CH(CH₃)–COOH + H₂N–CH₂–COOH.