A Combination Strategy of Multidrug-Sensitive Budding Yeast and Chemical Modifications Enabling to Find a New Overlooked Antifungal Compound, Sakurafusariene, from In-House Fractionated Library.

In this report, we disclose our discovery of a new antifungal natural product, sakurafusariene ( 1 ), from an in-house fractionated library of the culture broth of Fusarium sp. FKI-7550 strain by using a combination strategy of multidrug-sensitive yeast and chemical modification. Throughout our investigation, we encountered challenges in the isolation of natural product 1 . A chemical modification strategy via alkylation of 1 allowed for removal of the impurities enabling us to elucidate the structure of 1 . Furthermore, we synthesized ester derivatives using a method inspired by the isolation study of 1 , which gave us valuable information to understand a preliminary structure-activity relationship against Pyricularia oryzae growth inhibitory activity.