The following β-keto ester is synthesized through Claisen Condensation. Determine the structure of the ester(s) needed to produce this compound.

Structure of a β-keto ester needed for Claisen Condensation synthesis.

Another view of the β-keto ester for Claisen Condensation synthesis.

Alternative representation of the β-keto ester for Claisen Condensation.

Different angle of the β-keto ester structure for Claisen Condensation.