Lyngbya semiplena

Semiplenamides A 359 to G 365, a series of new anandamide-like fatty acid amides, were isolated from a 1997 Papua New Guinea collection of the marine cyanobacterium Lyngbya semiplena, and all these new metabolites displayed toxicity in the brine shrimp model system. Only semiplenamides A 359, B 360, and G 365 showed weak affinity for the rat cannabinoid CBl receptor. Semiplenamide A 364 was also a moderate inhibitor (IC50 = 18.1 pM) of the anandamide membrane transporter (AMT). Novel 5y -aldol/dehydration methodology was developed for the stereoselective synthesis of the core ( )-a, P-unsaturated amide functionality of this class of natural product, and employed for the efficient synthesis of semiplenamide... 

Isolated from the species Lyngbya semiplena collected at a shallow depth (1-3 m) in Wewak Bay, Papua New Guinea, the wewakpeptins A-D are cytotoxic depsipeptides which contain many nonribosomal amino acids such as 2,2-dimethyl-3-hydroxy-octanoic acid (Dhoaa) and 2,2-dimethyl-3-hydroxy-octynoic (Dhoya), as well as N-methy-lated amino adds such as N-methylvahne and N-methyl-alanine. A second lactone implies 2-hydroxy-isovaleric add (Hiva) for wewakpeptins A and B, and phenyllactic add (Pla) for wewakpeptins C and D. Wewakpeptins A and B are approximately tenfold more cytotoxic towards the lung cancer NCI-H460 than are wewakpeptins C and D (Han et al, 2005b). 

Wewakpeptin A (R = ethynyl Dhoya) Wewakpeptin B (R = ethyl Dhoaa) Lyngbya semiplena Han et al., 2005b... 

Han, B., McPhail, K.L., Ligresti, A., Di Marzo, V, and Gerwick, W.H. (2003) Semiplenamides A-G, fatty acid amides from a Papua New Guinea collection of the marine cyanobacterium Lyngbya semiplena. J. Nat. Prod., 66, 1364-1368. 

Kwan, J.C., Taori, K., Paul, V.J., and Luesch, H. (2009b) Lyngbyastatins 8-10, elastase inhibitors with cychc depsipeptide scaffolds isolated from the marine cyanobacterium lyngbya semiplena. Mar. Drugs, 7, 528-538. 

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