Asymmetric Synthesis of a New Helix-Forming beta-Amino Acid: trans-4-Aminopiperidine-3-carboxylic Acid

摘要

We report a synthesis of a protected derivative of trans-4-aminopiperidine-3-carboxylic acid (APiC). The route provides either enantiomer. All intermediates are purified by crystallization, and large-scale preparation is therefore possible. An analogous route provides either enantiomer of trans-2-aminocyclohexanecarboxylic acid (ACHC). We have previously shown that beta-peptide oligomers containing ACHC adopt a helical conformation defined by 14-membered C=O(i)…H-N(i-2) hydrogen bonds ("14-helix"). Here we show that APiC residues can be incorporated into the 14-helix.