gamma-Aromatic Butenolides of Microbial Source - A Review of Their Structures, Biological Activities and Biosynthesis

gamma-Aromatic butenolides (gamma-AB) are an important type of structures found in many bioactive microbial secondary metabolites (SMs). gamma-AB refer to a group of natural products (NPs) containing five-membered (unsaturated) lactones with 3-phenyl and 4-benzyl substituents. Their wide-range biological activities have inspired pharmaceutical chemists to explore its biosynthesis mechanisms and design strategies to construct the gamma-AB skeleton. Recently, there are a great deal of interesting research progress on the structures, biological activities and biosynthesis of gamma-AB. This review will focus on these aspects and summarize the important achievements of gamma-AB from 1975 to 2021.