(R)-1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethanamine (R)-2-acetamido-4-methylpentanoate

(R)-1-(3-Ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethylamine N-Acetyl-D-leucine Salt is an intermediate in the synthesis of (R)-Apremilast (A729705), an enantiomer of Apremilast (A729700), an oral phosphodiesterase 4 inhibitor is used in the treatment of psoriatic arthritis.