Single‐crystal‐to‐single‐crystal phase transition of 18β‐glycyrrhetinic acid isopropyl ester

Due to the destruction of the integrity of the parent crystal, single‐crystal‐to‐single‐crystal phase transition in organic compounds is still a relatively rare phenomenon. The phase transition in glycyrrhetinic acid isopropyl ester is triggered by temperature change. The increasing volume of the isopropyl substituent as a result of increasing temperature forces a remodelling of the structural motifs. These changes cause a single‐crystal‐to‐single‐crystal phase transition. The low‐temperature form is isostructural with glycyrrhetinic acid methanol solvate, while the high‐temperature phase is isostructural with the ethyl ester of this acid. The single‐crystal‐to‐single‐crystal phase transition observed for glycyrrhetinic acid isopropyl ester is triggered by temperature change and causes the rebuilding of the structural motifs. The low‐temperature phase is isostructural with glycyrrhetinic acid methanol solvate, while the high‐temperature phase is isostructural with glycyrrhetinic acid ethyl ester.