Cybastacines A and B: Antibiotic Sesterterpenes from a Nostoc sp. Cyanobacterium.
Alfredo H CabanillasVíctor Tena PérezSantiago Maderuelo CorralDiego Fernando Rosero ValenciaAntera Martel QuintanaMontserrat Ortega DoménechÁngel Rumbero SánchezPublished in: Journal of natural products (2018)
Cybastacines A (1) and B (2) were discovered as a novel pentacyclic sesterterpenoid-alkaloid skeleton structure, with a guanidinium group. These molecules were isolated from a Nostoc sp. cyanobacterium collected in the Canary Islands. Their structures were elucidated primarily by a combination of spectroscopic analyses and X-ray diffraction. These compounds showed antibiotic activities against several clinically relevant bacterial strains.