[Development of Novel Biologically Active Compounds Based on Synthetic Organic Chemistry]

The aging population has had an impact on society in recent decades. Aging-associated health issues are a particularly challenging aspect to regulate. Therefore, the extension of healthy life expectancy by the application of biologically active compounds is an attractive research topic in the fields of medicinal chemistry, chemical biology, and also organic synthesis. Herein, the first total synthesis of acaulide, acaulone A and 10-keto-acaudiol A is described. These compounds were originally isolated from a culture of Acaulium sp. H-JQSF. Acaulide exhibits anti-osteoporosis activity in a prednisolone-induced osteoporotic zebrafish model; hence, this natural product is expected to be a new lead compound for anti-osteoporosis drugs. The characteristic acaulide skeletons were synthesized via late-stage Michael addition inspired by the proposed biosynthetic pathways. The conformational analysis of the 14-membered macrodiolide revealed the specific conformation that enabled the late-stage stereoselective functionalization.