Lipopurealins

Kobayashi J, Honma K, Tsuda M, Kosaka T (1995) Lipopurealins D and E and Purealidin H, New Bromotyrosine Alkaloids from the Okinawan Marine Sponge Psammaplysilla purea. J Nat Prod 58 467... 

Lipopurealins A (141), B (142), and C (143) are unique metabolites with a long alkyl chain, isolated from the marine sponge Psammaplysilla purea by Kobayashi s group in 1986 102). Lipopurealins are inhibitors of Na,K-ATPase, and Upopurealin B is most active. Two additional lipopurealins, lipopurealins D (144) and E (145) were isolated from... 

Lipopurealin-A (141), lipopurealin-B (142), and lipopurealin-C (143) exhibited inhibitory activities on Na,K-ATPase from porcine brain and dog kidney, lipopurealin-B being the most potent inhibitor. In cardiac Na,K-ATPase all three alkaloids showed only weak activity. In addition, myosin K,EDTA-ATPase was markedly activated by purealin, whereas the enzyme was inhibited by lipopurealin-B (202). Purealidin A (146) showed weak inhibitory activity (22% inhibition at 10 M) on Na,K-ATPase, and had no effect on myosin K,EDTA-ATPase. These results suggest that the acryl part of purealin (122), lacking in purealidin A (146), is important for the activity of these ATPase inhibitors (J04). lanthesines B (106), C (93), and D (107) exhibited inhibitory activity against dog kidney Na,K-ATPase with IC50 values of 440, 50, and 280 pM,... 

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