Enediyne antitumour antibiotics

An enediyne antitumour antibiotic, namenamicin (185) was isolated from Polysyncraton lithostrotum from Fiji [176]. 

A new enediyne antitumour antibiotic, namenamycin (59), has been isolated from the marine ascidian Polysyncraton lithostrotum. This structure has a significantly different mode of linkage between rings A and B in the trisaccharide, as compared with the hydroxylamino link in the calicheamicins. A dimer of the... 

The S3 unit is also to be found in compounds of natural origin [28, 32, 33]. A very simple one, isolated from an edible mushroom, exhibits both S2 and S3 moieties [34, 35]. 5-Methylthio-l,2,3-trithiane [28] is another example close to charatoxin, and the presence of an allylic trisulfide, and its role as a triggering device for their antitumour activity, in enediyne antibiotics [36,37], is truly astonishing. 

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