Antibacterials phloeodictine

The antibacterial and cytotoxic bicyclic alkaloid phloeodictine B (473) was isolated from a New Caledonian species of Phloeodictyon and is unusual as it contains a cyclic aminoketal functionality. The structure was proposed on the basis of spectral data [398], A Phloeodictyon sp. from New Caledonia contained the cytotoxic and antibiotic alkaloids, phloeodictines Ci (474) and C2 (475). Their structures were elucidated by mass spectrometry and NMR spectroscopy [399]. 

Phloeodictines A-A1-A2 Phloeodictyon sp. Antibacterial and cytotoxic activities (KB cells)... 

The phloeodictines form a series of a dozen derivatives of 2,3,4,6-tetrahydropyrrolo-[l,2-a]-pyrimidine substituted with two fatty chains, including one bearing a guanidine. All of these antibacterial and cytotoxic derivatives were isolated from one undetermined species of the genus Phloeodictyon harvested in New Caledonia (Kourany-Lefoll et al., 1992, 1994). New members of this series were isolated from the New Caledonian shallow-water sponge... 

Kourany-Lefoll, E., Pais, M., Sevenet, T., Guittet, E Montagnac, A., Fontaine, C., Guenard, D., Adeline, M., and Debitus, C. (1992) Phloeodictines A and B new antibacterial and cytotoxic bicyclic amidinium salts from the New Caledonian sponge Phloeodictyon sp. J. Org. Chem., 57, 3832-3835. 

Aplysillamides A and B are antibacterial and antifungal amides formed from an acid with 10 carbon atoms and the amine agmatine, which is formally derived by the decarboxylation of arginine and has already been encountered in certain metabolites of cyanobacteria (see Chapter 8) as well as in phloeodictins (see above). These two atypical derivatives of guanidine were isolated from the... 

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