Abstract
Tunicates (ascidians) are common marine invertebrates that are an exceptionally important source of natural products with biomedical and pharmaceutical applications, including compounds that are used clinically in cancers. Among tunicates, the genusDidemnumis important because it includes the most species, and it belongs to the most speciose family (Didemnidae). The genusDidemnumincludes the speciesD.molle,D.chartaceum,D.albopunctatum, andD.obscurum, as well as others, which are well known for their chemically diverse secondary metabolites. To date, investigators have reported secondary metabolites, usually including bioactivity data, for at least 69 members of the genusDidemnum, leading to isolation of 212 compounds. Many of these compounds exhibit valuable biological activities in assays targeting cancers, bacteria, fungi, viruses, protozoans, and the central nervous system. This review highlights compounds isolated from genusDidemnumthrough December 2019. Chemical diversity, pharmacological activities, geographical locations, and applied chemical methods are described.