Aspartic protease inhibitors via C1-homologation of peptidic aldehydes and studies on reduced amide isosteres

(R)-Configured isophthalic hydroxyethylamines play an important role in the inhibition of β-secretase (BACE1). We present the synthesis of a number of (S)-configured hydroxyethylamine derivatives via 2-iodoethanol intermediates and the comparison with the (R)-analogues. An N-substituted indole was investigated as a substitute for the isophthalamide moiety.