Halopytis incurvus

The toxic Japanese gastropod Turbo marmorata contains the two toxins, turbotoxins A (1983) and B (1984), isolated as bis-trifluoroacetates (1824, 1825). The turbotoxins A and B show LD99 = 1.0 and 4.0 mg kg 1 in mice. The simple iodinated ammonium salt 1985 is also found in this animal (1826). The red alga Halopytis incurvus contains the simple brominated phenols 1986 and 1987, which were isolated as the methyl esters and methyl ethers (1827). These presumed degradation products of tyrosine are related to earlier reported brominated metabolites (1). 

Chantraine J-M, Combaut G, Teste J (1973) Bromophenols of a Red Algae, Halopytis incurvus. Carboxylic Acids. Phytochemistry 12 1793... 

Chantraine, J.-M., Combaut, G., Teste, J. Phenols bromes d lme algue rouge, Halopytis incurvus Acides carboxyliques. Phytochemistry 1973, 12, 1793-1796. 

Constit. of the alga Halopytis incurvus. Needles (EtOH aq.). Mp 208° dec. Nat. prod. isol. as the a,4-di-Me ether of the enol form. 

Giiven KC, Kizil Z (1985) The content of volatile oil of Halopytys incurvus (Huds.) Batters (Rhodophyceae). Acta Pharm Tuic 27 54-56... 

Quite surprisingly V. aerophoba failed to incorporate radioactivity from [U- " C]-L-tyrosine into aerothionin (7), aeroplysinin-1 (4) and the dienone (1) inactive aerothionin was also isolated when the animals were fed with [U- " C]-L-ornithine (71). However the sponges utilized these aminoacids for the synthesis of fatty acids. A very slow rate of biosynthesis might account for these results. A dietary origin for these compounds can be also suspected in this connection the recent report of the isolation of the brominated esters (19) and (20) (after methylation) from hydrolyzed extracts of the red alga Halopytis incurvus (41) seems relevant. 

Chantraine, j. M., G. Combaut, and J. Teste Phenols Bromes d une Algue Rouge, Halopytis incurvus Acides carboxyliques. Phytochem. 12, 1793 (1973). 

---