How is 3-Amino-3-(4-hydroxyphenyl)propanoic acid (CAS: 6049-54-3) typically synthesized?

3-Amino-3-(4-hydroxyphenyl)propanoic acid is typically synthesized through the coupling of 4-hydroxybenzaldehyde with alanine. The reaction involves the condensation of these two molecules in the presence of a suitable catalyst such as p-toluene sulfonic acid (p-TSA) or other Lewis acids. The yield is generally good with selectivity towards the desired diastereomer. The reaction is carried out in aqueous media, and the product can be isolated by recrystallization.