Clavularia viridis

Clavulones I and II are members of an unusual family of marine prostanoids from the coral Clavularia viridis which are biosynthesiied by a cationic (i.e. non-radical, non-endoperoxide) pathway. The total synthesis of clavulones I and II was accomplished from cyclopentadiene as SM goal. 

Extracts from Clavularia viridis and also many other coral species convert arachidonic acid to the prostanoidpreclavulone-A via 8-( f )-hydroperoxy-5,ll,14( Z), QfEj-eicosatetraenoic acid. The carbocyclization is considered to occur from allene oxide and oxidopentadienyl cation intermediates. An enantioselective total synthesis of preclavulone-A was developed to assist the biosynthetic research. 

Scheme 10. Proposed biosynthesis of clavulone I (88) in Clavularia viridis [85]...

Iwashima, M. Okamoto, K. Miyai, Y. Iguchi, K. (1999) 4-Epiclavulones, new marine prostanoids fixm the Okinawan soft coral, Clavularia viridis. Chem. Phaim. Bull., 47, 884-6. 

A practical racemic synthesis of the known chlorovulone II from the Okinawan soft coral Clavularia viridis has been accomplished (922). This coral has more recently afforded the new prostanoids 852-856 (923), 857-871 (924), and, from a Taiwanese collection, 872, 873 in addition to 857 and 858 (925). The absolute configuration of the previously known punaglandin 8 (852, X = Cl) was determined as shown (923). This soft coral also contains several non-halogenated possible biosynthetic precursors to these halogenated metabolites (926). 

Iwashima M, Nara K, Nakamichi Y, Iguchi K (2001) Three New Chlorinated Marine Steroids, Yonarasterols G, H and I, Isolated from the Okinawan Soft Coral, Clavularia viridis. Steroids 66 25... 

Watanabe K, Sekine M, Takahashi H, Iguchi K (2001) New Halogenated Marine Prostaglandins with Cytotoxic Activity from the Okinawan Soft Coral Clavularia viridis. J Nat Prod 64 1421... 

Shen Y-C, Cheng Y-B, Lin Y-C, Guh J-H, Teng C-M, Ko C-L (2004) New Prostanoids with Cytotoxic Activity from Taiwanese Octocoral Clavularia viridis. J Nat Prod 67 542... 

Iwashima, M., Watanabe, K., and Iguche, K., New marine prostanoids, preclavulone lactones, from the Okinawan soft coral Clavularia viridis, Tetrahedron Lett., 38, 8319, 1997. 

Punaglandin-I (305) Clavularia viridis Octacoral, Telesio riisei HSV [155]... 

Clavularia viridis, 1 Clofibrate, 540 Clonal senscence, 539 Clostridium butyricum, 501 Clostridium perfringens, 509 Clover-leaf lipids, 163 Clupanodon melanostica, 133 Clupeiformes, wax esters, 147 Cobalt octanoate, 246 Cockroaches, 145... 

Source Clavularia viridis Mol. formula 20 00 Mol. wt. 302 Solvent CDCL... 

Kobayashi, M., T. Yasuzawa, M. Yoshihara, H. Akutsu, Y. Kyogoku, and I. Kitagawa Four New Prostanoids Claviridenone-A, -B, -C, and -D from the Okinawan Soft Coral Clavularia viridis. Tetrahedron Lett. 23, 5331 (1982). 

Kikuchi, H., Y. Tsukitani, K. Iguchi, and Y. Yamada Clavulones, New Type of Prostanoids from the Stolonifer Clavularia viridis Quoy and Gaimard. Tetrahedron Lett. 23, 5171 (1982). 

Clavularia viridis Quoy and Gaimard. Tetrahedron Lett. 24, 1549 (1983). 

Considering the phylum Cnidaria the class Anthozoa comprises 99.0% of NMNPl and the subclass Octocorallia account for the most NMNPl in the Anthozoa (95.5%) the order Alcyonacea account for 98.1% of new natural products from Octocorallia and 26.8% of all NMNPl. The most product-rich genera are Sinularia (11.9%), Briareum (11.2%), Pseudopterogorgia (6.6%), Sarcophyton (6.1%), and Nephthea (5.2%). The genera in which most new natural products were reported between decades were Nephthea (+468.2% from 22 to 125 natural products), Clavularia (+255.2% from 29 to 103 nam-ral products), Junceella (+229.2% from 24 to 79 natural products), and Sarcophyton (+89.8% 59 to 112 natural products). Of Cnidaria species, Clavularia viridis, Pseudopterogorgia elisabethae, and Briareum excavatum account for the highest number of NMNPl reported since 1990, and each accounts for approximately 3% of all cnidarian s NMNPl [1]. 

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