Enantioselective Self-Replicators

Self-replicating molecules provide a simple approach for investigating fundamental processes in scenarios of the emergence of life. Although homochirality is an important aspect of life and of how it emerged, the effects of chirality on self-replicators have received only little attention so far. Here, we report several self-assembled self-replicators with enantioselectivity that emerge spontaneously and grow only from enantiopure material. These require a relatively small number of chiral units in the replicators (down to eight) and in the precursors (down to a single chiral unit), compared to the only other enantioselective replicator reported previously. One replicator was found to incorporate material of its own handedness with high fidelity when provided with a racemic mixture of precursors, thus sorting (L)- and (D)-precursors into (L)- and (D)-replicators. Systematic studies reveal that the presence or absence of enantioselectivity depends on structural features (ring size of the replicator) that appear to impose constraints on its supramolecular organization. This work reveals new aspects of the little researched interplay between chirality and self-replication and represents another step toward the de novo synthesis of life.