Title
Ceratinadins E and F, New Bromotyrosine Alkaloids from an Okinawan Marine Sponge Pseudoceratina sp.
Author
Shin-ichiro Kurimoto, Taito Ohno, Rei Hokari, Aki Ishiyama, Masato Iwatsuki, Satoshi Ōmura, Jun’ichi Kobayashi, Takaaki Kubota
Year
2018
Journal
Marine Drugs
Abstract
Two new bromotyrosine alkaloids, ceratinadins E (1) and F (2), were isolated from an Okinawan marine sponge Pseudoceratina sp. as well as a known bromotyrosine alkaloid, psammaplysin F (3). The gross structures of 1 and 2 were elucidated on the basis of spectroscopic data. The absolute configurations of 1 and 2 were assigned by comparison of the NMR and ECD data with those of a known related bromotyrosine alkaloid, psammaplysin A (4). Ceratinadins E (1) and F (2) are new bromotyrosine alkaloids possessing an 8,10-dibromo-9-methoxy-1,6-dioxa-2-azaspiro[4.6]undeca-2,7,9-trien-4-ol unit with two or three 11-N-methylmoloka’iamine units connected by carbonyl groups, respectively. Ceratinadin E (1) exhibited antimalarial activities against a drug-resistant and a drug-sensitive strains of Plasmodium falciparum (K1 and FCR3 strains, respectively).
Full Article
Instrument
J-1500
Keywords
Circular dichroism, Absolute configuration, Pharmaceutical