The marine sponge Agelas citrina as a source of the new pyrrole–imidazole alkaloids citrinamines A–D and N-methylagelongine

• Christine Cychon,
• Ellen Lichte and
• Matthias Köck

Beilstein J. Org. Chem. 2015, 11, 2029–2037, doi:10.3762/bjoc.11.220

• Christine Cychon Ellen Lichte Matthias Kock Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany 10.3762/bjoc.11.220 Abstract The chemical investigation of the Caribbean sponge Agelas citrina revealed four new pyrrole–imidazole

• ) which consist of a pyridinium ring and an ester linkage instead of the aminoimidazole moiety and the common amide bond in PIAs. Keywords: Agelas citrina; marine sponges; mauritiamine; NMR; pyrrole–imidazole alkaloids; Introduction The family of pyrrole-imidazole alkaloids (PIAs) represents a

• [1]. The chemical investigation of the Caribbean sponge Agelas citrina yielded the following known monomeric PIAs: hymenidin (6) [2], keramadine (13) [3], dispacamide B (14) [4], mukanadin B (15) [5], 2-debromotaurodispacamide A (16) [6], tauroacidin B (17) [7], and the dimeric PIA benzosceptrin B