Erratum to: Isolation of Agelasin B from the Marine Fungus Agelas cf. mauritiana

Fungi of the genus Agelas provide a source of three principal structural classes of biologically active compounds [1]. These are brominated natural pyrroles [2], -cerebrosides [3], and compounds of mixed biogenesis consisting of diterpenoid fragments and 9-methyladenine residues [4–10]. In continuation of the search for biologically active alkaloids in marine invertebrates [11–13], the alkaloid agelasin B (1), a metabolite of mixed biogenesis that was previously isolated only from A. nakamurai [7], was isolated for the first time from A. cf. mauritiana collected during the 45th expedition of the RV Akademik Oparin off the shores of Vietnam (08°44.9N, 106°39.6E, 10 m depth). We used the rapid and convenient method that we developed to isolate the alkaloids. The fungus (30 g dry wt.) was extracted with EtOH, a part of which (30 mL) was concentrated in vacuo. The residue was chromatographed over a microcolumn with YMC Gel ODS-A reversed-phase sorbent (7.5 m) using aqueous EtOH (40%) and then EtOH (65%)–TFA (0.1%). The eluates with TFA were evaporated. The compounds were isolated by HPLC on a Shimadzu instrument with an RID-10A differential refractometer using a YMC-ODS-A column (10 250 mm) and EtOH (65%)–TFA (0.1%) to afford 1 (7.3 mg). The molecular formula C26H39N5 of 1 was confirmed by HR-ESI-MS data: found m/z 422.3293 [M + H] +; calcd m/z 422.3278.