Most organic compounds have the property of "chirality" in which the image reflected in the mirror does not overlap with the original image (relationship between the right hand and the left hand).In the case of pharmaceuticals, the difference between the right hand and the left hand can be a drug or a poison, so it is always a major research theme to selectively synthesize, identify, and separate one of them.

　Previous studies have shown that compounds such as rotaxanes exhibit a characteristic asymmetry called "topological chirality" due to the entanglement of non-asymmetric ring-like molecules with non-asymmetric dumbbell-like molecules.However, it has long been a question of whether these molecules, which have no asymmetry in their original constituents, really function as an asymmetric source.

　This time, the research group discovered for the first time that even if rotaxane, which is a topological chirality, is used as an asymmetric source, it is possible to induce a one-sided helix in the same way as a normal asymmetric source, and the answer to the question was obtained. ..Also, surprisingly, the addition of the common "point asymmetry" as an asymmetric source did not induce a one-sided helix, only a one-sided helix based on topological chirality.This suggests that compounds with topological chirality have better functions than conventional asymmetric sources.

　This result is expected to lead to the development of excellent functional molecules that achieve selective synthesis, recognition, and division of asymmetric molecules in the future.

Paper information:[Angewandte Chemie International Edition] Induction of Single-Handed Helicity of Polyacetylenes Using Mechanically Chiral Rotaxanes as Chiral Sources