A new 20-membered macrolide designated exiguolide has been isolated from the marine sponge Geodia exigua, and its structure determined by interpretation of spectroscopic data. Exiguolide specifically inhibited fertilization of sea urchin (Hemicentrotus pulcherrimus) gametes but not embryogenesis of the fertilized egg.

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One novel and three known hydroxycinnamic acid derivatives having antioxidant activities were isolated from a Brazilian bee pollen. They were identified as kaempferol 3-O-[2-O-p-coumaroyl]-alpha-L-arabinopyranoside, N(1), N(5), N(10)-tri-p-coumaroyl spermidine, N(1), N(5), N(10), N(14)-tetra-p-coumaroyl spermine, and monocaffeoyl-tri-p-coumaroyl spermine, respectively. The structure of the kaempferol glycoside was established on the basis of spectroscopic and chemical investigations. Among the isolated compounds, monocaffeoyl-tri-p-coumaroyl spermine showed the strongest free radical-scavenging activity, which was almost identical to that of alpha-tocopherol. On the other hand, the antioxidant effect of tri-p-coumaroyl spermidine on autooxidation of linoleic acid was strongest and nearly equal to that of alpha-tocopherol.

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