Homochirality of β-Peptides: A Significant Biomimetic Property of Unnatural Systems.

Homochirality, an interesting phenomenon of life, is mainly an unresolved problem and was thought to be a property of living matter. Herein, we show that artificial β-peptides have the tendency toward homochiral diastereoselective chain elongation. Chain-length-dependent stereochemical discrimination was investigated in the synthesis of foldamers with various side chains and secondary structures.

Enzymatic Strategy for the Resolution of New 1-Hydroxymethyl Tetrahydro-β-carboline Derivatives in Batch and Continuous-Flow Systems.

Many alkaloids containing a tetrahydro-β-carboline skeleton have well-known therapeutic effects, leading to increased interest in the synthesis of these natural products. Enantiomers of N-Boc-protected 1-hydroxymethyl-1,2,3,4-tetrahydro-β-carboline [(±)-7], 1-hydroxymethyl-6-methoxy-1,2,3,4-tetrahydro-β-carboline [(±)-8], and 1-hydroxymethyl-6-fluoro-1,2,3,4-tetrahydro-β-carboline [(±)-9] were prepared through enzymecatalyzed asymmetric acylation of their primary hydroxyl group. The preliminary experiments were performed in a continuous-flow system, while the preparative-scale resolutions were done as batch reactions.