Nonhalogenated and halogenated phlorotannins from the brown alga carpophyllum angustifolium

Using HPLC, forty-five phloroglucinol derivatives were obtained from an ethanolic extract of the brown alga Carpophyllum angustifolium after peracetylation. Compounds of the fuhalol-B series are described. The structure of hydroxyheptafuhalol-B nonadecaacetate is confirmed by the addition of (13)C NMR spectral data, octafuhalol-C heneicosaacetate is described for the first time. The occurrence of four halogenated phlorotannins is reported: 2-chlorophloroglucinol triacetate, 2[D']iododiphlorethol pentaacetate, which had been isolated formerly only as a mixture, 3[A]chlorobifuhalol hexaacetate, and 3[A(4)]chlorodifucol hexaacetate. All substances were characterized by means of spectral analysis.