A research group led by Associate Professor Shoji Kobayashi of the Department of Applied Chemistry at Osaka Institute of Technology (President: Shin Inoue) has discovered a simple method to produce various oxysterols related to mushroom growth and efficacy, and has clarified the precise stereochemical structures of sterols that were previously unclear. Sterols are molecules produced in the bodies of animals, plants, and fungi, and are thought to be deeply involved in the efficacy of foods. The results of this research are expected to lead to the elucidation of the stereochemical structures of highly oxidized sterols and the biosynthetic pathways of sterols in vivo, which will be useful for the development of pharmaceuticals and other products. Key Points of This Research: * Simple and comprehensive synthesis of various sterols using chemical species that can exist in vivo * Development of a method to directly introduce an oxygen functional group into the CD ring of the steroid skeleton, which is rarely achieved. * Clarification of the stereochemical structure of quaternary carbon centers in the steroid skeleton, which were difficult to analyze with conventional methods. Outline Diagram of This Research Sterols are one of the main components produced in the bodies of animals, plants, and fungi. In animals such as humans, they are thought to be produced mainly from cholesterol, and in fungi, mainly from ergosterol. In mushrooms, which are fungi, sterol components are thought to be deeply involved in taste and efficacy. The diversity of structures of sterols produced by fungi is thought to be due to the oxidation of various parts of the steroid skeleton through oxidative metabolism within the fungal cells, accompanied by various functional group transformations and cleavage/formation of bonds. Based on a self-devised hypothesis for sterol biosynthesis, this research group discovered a method to directly oxidize the CD ring of the steroid skeleton, which has low reactiv