Patent ID: 7141263

Claim:
A process for producing an aspartyl dipeptide ester derivative represented by the following formula (IV) or a salt thereof: wherein R is a hydrogen atom, a lower alkyl group having 1 to 4 carbon atoms, or a lower alkoxy group having 1 to 4 carbon atoms, comprising: reacting a benzaldehyde derivative represented by the following formula (I): with acetaldehyde in the presence of an alkali, to produce a a cinnamaldehyde derivative represented by the following formula (II) or a salt thereof: subjecting the cinnamaldehyde derivative representative formula (II) to a reaction for reducing a carbon-carbon double bond selectively with hydrogen in the presence of a reduction catalyst, to produce a propionaldehyde derivative represented by the following formula (III): subjecting the propionaldehyde derivative represented by formula (III) and an aspartame to a reductive alkylation reaction, wherein R is a hydrogen atom, a lower alkyl group having 1 to 4 carbon atoms, or a lower alkoxy group having 1 to 4 carbon atoms.