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Minutissamides E-L, antiproliferative cyclic lipodecapeptides from the cultured freshwater cyanobacterium cf. Anabaena sp.

Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, IL 60612, USA.
Bioorganic & medicinal chemistry (Impact Factor: 2.82). 08/2012; 20(20):6134-43. DOI: 10.1016/j.bmc.2012.08.017
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ABSTRACT The extract of UIC 10035, a strain obtained from a sample collected near the town of Homestead, South Florida, showed antiproliferative activity against MDA-MB-435 cells. Bioassay-guided fractionation led to the isolation of a series of cyclic lipodecapeptides, named minutissamides E-L (1-8). The planar structures were determined by analysis of HRESIMS, tandem MS, and 1D and 2D NMR data, and the stereoconfigurations were assigned by LC-MS analysis of the Marfey's derivatives after acid hydrolysis. Minutissamides E-L (1-8) exhibited antiproliferative activity against MDA-MB-435 cells with IC(50) values ranging between 1 and 10μM. The structures of minutissamides E-L (1-8) were closely related with those of the previously reported lipopeptides, puwainaphycins A-E and minutissamides A-D, characterized by the presence of a lipophilic β-amino acid and three non-standard amino acids NMeAsn, OMeThr and Dhb (α,β-dehydro-α-aminobutyric acid). The strain UIC 10035 was designated as cf. Anabaena sp. on the basis of morphological and 16S rRNA gene sequence analyses.

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