Studies on chemical constituents of the brown alga Dictyopteris divaricata / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the chemical constituents of the brown alga D. divaricata, and to test cytotoxicities of the purified compounds.</p><p><b>METHOD</b>Compounds were isolated by normal phase silica gel, Sephadex LH-20 chromatography and reverse phase HPLC techniques. Their structures were elucidated by spectroscopic methods including IR, MS and NMR. Cytotoxicities were tested by MTT method.</p><p><b>RESULT</b>Eight compounds were isolated from ethanolic extract of the brown alga D. divaricata and their structures were identified as (-)-torreyol (I), 4beta, 5alpha-dihydroxycubenol (II), 3-farnesyl-p-hydroxybenzioc acid (III), chromazonarol (IV), fucosterol (V), phenyl acetylamine (VI), 4-hydroxybenzoic acid (VII) and n-hexadecanoic acid (VIII).</p><p><b>CONCLUSION</b>Compound II and IV were obtained from this alga for the first time. The others were isolated from the Dictyotaceae algae for the first time. All compounds were inactive (IC50 > 10 microg x mL(-1)) against human tumor cell lines KB, Bel-7402, PC-3M, Ketr 3 and MCF-7.</p>

Bromophenols from the brown alga Leathesia nana / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the chemical constituents of the brown alga Leathesia nana.</p><p><b>METHOD</b>Compounds were isolated by normal phase silica gel, Sephadex LH-20 chromatography and reverse phase HPLC techniques. Their structures were elucidated with spectroscopic methods including IR, MS and NMR.</p><p><b>RESULT</b>Six compounds were isolated from ethanolic extract of the brown alga L. nana and their structures were identified as 2,2',3,3'-tetrabromo-4,4',5,5'-tetrahydroxydiphenyl methane, 2,2',3-tribromo-3', 4,4', 5-tetrahydroxy-6'-ethyloxymethyldiphenyl methane, 2,3-dibromo-4,5-dihydroxybenzyl alcohol, 2,3-dibromo-4,5-dihydroxybenzyl methyl ether, 3-bromo-4-hydroxybenzoic acid and 2-bromo-4,5-dihydroxybenzaldehyde.</p><p><b>CONCLUSION</b>All these compounds were obtained from this species for the first time.</p>