Nostoc spongiaeforme

Borophycin and four new cyclic hexapeptides containing no boron, tenuecyclamides A-D, were also isolated from the methanol extract of Nostoc spongiaeforme var. tenue collected in the Volcani Center, Israel. The yield was 0.1% on the basis of the dry weight of the blue-green alga [54]. 

Compounds isolated from the genus Nostoc (order Nostocales, 73 compounds) have predominantly been isolated from unknown species (91%). Nostoc commune accounts for only 6% of the isolated compounds with Nostoc linckia, Nostoc muscorum, and Nostoc spongiaeforme, each responsible for about 1 %. 

C5H5N5O, Mr 151.13, black needles, mp. 171 -172 °C or violet powder. Black-violet pigment from the freshwater cyanobacterium Nostoc spongiaeforme. It exhibits broad growth inhibiting action. 

Borophycin Nostoc spongiaeforme var. tenue cancer prevention 52... 

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