Sulfated bromophenols from Osmundaria obtusiloba (C. Agardh) R. E. Norris (Rhodophyta, Ceramiales)

Abstract

Two new sulfated oligobromophenols from the marine red algae Osmundaria obtusiloba, 4-(1′-potassium sulfate, 2,3-dibromo, 1′,4,5- trihydroxybenzyl) - 4″-(1‴-potassium sulfate, 2″,3″- dibromo, 1‴,4″,5″-trihydroxybenzyl) sulfate and 1′-(2, 3-dibromo, 4-potassium sulfate, 1′, 4, 5-trihydroxybenzyl) - 4″-(1‴ potassium sulfate, 2″, 3″-dibromo, 1‴, 4″, 5″ trihydroxybenzyl) sulfate, are herein reported. Besides them it was obtained 2, 2′, 3, 3′-tetrabromo-4, 4′, 5, 5′-tetrahydroxydiphenylmethane, 2, 3-dibromo-p-hydroxybenzyl methyl ether (methyl lanosol), dipotassium 2,3-dibromo-5-hydroxybenzyl 1′,4-disulfate, 24-methylenecolest-5-en-3-β-ol and α-D-mannopyranosyl- (1→2′)-glycerate (digeneaside). The structures were determined by analysis of the spectroscopic data (IR, NMR and MS) and comparison with the literature. The 13CNMR data for dipotassium 2,3-dibromo-5- hydroxybenzyl-1′,4-disulfate are described here for the first time. The present study also suggests a mild method to isolate and to purify sulfated compounds.