Eudistomins antimicrobial activity

Eudistomin K (155) (135) and its sulfoxide (171) (136) were isolated from the New Zealand ascidian Ritterella sigillinoides. The sulfoxide (171) also shows antiviral activity. The structure of 155 was determined by X-ray analysis (137) and that of 171 by semisynthesis from 155. Three other /3-carbolines, named eudistomins R, S, and T (172-174) were obtained from a Bermudian tunicate (E. olivaceum) by using an amino-bonded HPLC column (138). A 2-methyl-1,2,3,4-tetrahydro- -carboline with an /V-methylpyrrolidine at C-l, named woodinine (175), was isolated from a New Caledonian ascidian (Eudistoma fragum) (139), extracts of which exhibit antimicrobial activity. 

The 6-bromo and 7-bromo derivatives of norharman (13), known as eudistomin N and O, respectively, have been shown to have both antiviral and antimicrobial activity <87JA3378>. Compound (13) and some of its derivatives, including tetrahydro derivatives, were investigated for their ability to bind to benzodiazepine receptors in the brain. Trends showed that fully aromatic deriva-... 

The bioactivity of the dihydro-P-carboline isoeudistomin U (165) was reported to be similar to that of eudistomin U it was not cytotoxic to CEM human leukemia lymphoblasts, nor did it exhibit antimicrobial activity against marine bacterial strains, although it exhibited strong activity against Agrobacterium tumefaciens [95]. No activity data was reported for (166) [115]. 

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