Cytotoxic depsipeptides

The receptors of ecological interactions are still not well understood. In fact, many ecological studies have failed to demonstrate well-defined roles for natural products (Pawlik 1993). Most experimental evidence for natural product receptors derives from biomedical applications. Kahalalide F, for example, is a potent cytotoxic depsipeptide (see Sect. 1.3.2.3) initially found in the sacoglossan mollusc Elysia rufescens and later in the green alga it feeds upon (Hamann and Scheuer... 

A deepwater species of Discodermia contained the cytotoxic depsipeptide, polydiscamide A (426), which was identified by spectroscopic means, chemical degradation and derivatisation [357],... 

Halicylindramides A-C (427-429) are antifungal and cytotoxic depsipeptides from Halichondria cylindrata from Japan [358]. Two additional peptides, halicylindramides D (430) and E (431) of which the former is antifungal and cytotoxic, were also isolated from a Japanese collection of H. cylindrata [359],... 

Li H, Matsunaga S, Fusetani N (1995) Halicylindramides A-C, Antifungal and Cytotoxic Depsipeptides from the Marine Sponge Halichondria cylindrata. J Med Chem 38 338... 

Wang, G., Kuramoto, M., Yamada, K., Yazawa, K., and Uemura, D., Homocereulide, an extremely potent cytotoxic depsipeptide from the marine bacterium Bacillus cereus, Chem. Lett., 791, 1995. 

Though kulokekahilide-1 has been isolated from the marine mollusk Philinopsis spedosa, this cytotoxic depsipeptide might originate from dietary cyanobacteria. J. Kimura, Y. Takada, T. Inayoshi, Y. Nakao, G. Goetz, W. Y. Yoshida, P. J. Scheuer, /. Org. Chem. 2002, 67, 1760-1767. 

Synthesis of arenastatin A (172), an extremely potent cytotoxic depsipeptide, involves the coupling of p-alanine 2-(trimethylsilyl)ethyl ester (170) and the D,0-methyltyrosine derivative (171) using DEPC.67,68... 

The Sodwana Bay sponge Hemiastrella minor (Family Hemiasterellidae) yielded three cytotoxic depsipeptides, the known ichthyotoxic, antihelminthic and antifungal jaspamide (75) [77] and the related hemiasterlin (76) and geodiamolide TA (77) [78]. Although the structures of 75 - 77 were elucidated from NMR and mass data, a paucity of material prevented degradation studies to establish the absolute... 

The structure of aurilide, a cytotoxic depsipeptide from the sea hare Dolabella auricularia has been elucidated by Suenaga et a/. with the help of Vhh couplings. 

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). 

Discovered in the early 1980s in spedes of the genus Trididemnum harvested in the Caribbean during the Alpha Hehx" expedition, the didemnins are a group of strongly antiviral and cytotoxic depsipeptides didemnin B is the first molecule of marine origin that has entered Phase II... 

Scleritodermin A is a new cytotoxic depsipeptide isolated from the species Sckritoderma nodosum harvested at a depth of 50 m in the Philippines. Its structure is characterized by the presence of a conjugated thiazole and two... 

Kobayashi, M Aoki, S.J., Ohyabu, N Kurosu, M Wang, W.Q., and Kitagawa. 1. (1994d) Arenastatin A, a potent cytotoxic depsipeptide from the Okinawan marine sponge Dysidea arenaria. Tetrahedron Lett., 35, 7969-7972. 

Li, H.-Y, Matsunaga, S., and Fusetani, N. (1995b) Halicylindramides A-C, antifungal and cytotoxic depsipeptides from the marine sponge Halichondria cylindrata. J. Med. Chem., 38, 338-343. 

Kobayashi, M., Kurosu, M Wang, W, and Kitagawa, 1. (1994) A total synthesis of arenastatin A, an extremely potent cytotoxic depsipeptide, from the Oldnawan marine sponge Dysidea arenaria. Chem. Pharm. Bull., 42, 2394-2396. 

White, J.D., Hong,., and Robarge, L.A. (1998) A concise synthesis of the cytotoxic depsipeptide arenastatin A. Tetrahedron Lett, 39, 8779-8782. 

Kotoku, N., Narumi, F., Kato, T Yamaguchi, M., and Kobayashi, M. (2007) Stereoselective total synthesis of arenastatin A, a spongean cytotoxic depsipeptide. Tetrahedron Lett., 48, 7147-7150. 

Shioiri, T, Imaeda, T, and Hamada, Y. (1997) An expeditious synthesis of geodiamolide A, an 18-membered cytotoxic depsipeptide from marine sponges. Heterocycles, 46, 421-442. 

Kimura, J., Takada, Y, Inayoshi, T, Nakao, Y, Goetz, G Yoshida, W.Y., and Scheuer, P,J, (2002) KulokekahUide-l, a cytotoxic depsipeptide from the cephalaspidean mollusk Philinopsis speciosa. J. Org. Chem., 67,1760-1767,... 

Rodriguez, J., Fernandez, R, Quinoa, E., Riguera, R., Debitus, C., and Bouchet, P. (1994) Onchidine a cytotoxic depsipeptide with C2 symetry from a marine mollusc. Tetrahedron Lett., 35, 9239-9242. 

Suenaga, K Mutou, T, Shibata, T, Itoh, T, Fujita, T, Takada, N., Hayamizu, H., Takagi, M., Irifime, T, Kigoshi, H and Yamada, K. (2004) Aurilide, a cytotoxic depsipeptide from the sea hare Dolabella auricularia isolation, structure determination, synthesis, and biological activity. Tetrahedron, 60, 8509-8527. 

Rinehart, K.L., Gloer, J.B., and Carter Cook, J.Jr, Mizsak, S.A., and Scahill, TA. (1981b) Structures of the didemnins, antiviral and cytotoxic depsipeptides from a Caribbean tunicate. J. Am. Chem. Soc., 103,1857-1859. 

Kahalalides Cytotoxic Depsipeptides of the Coupled Elysia sp./Bryopsis sp. 

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