Siphonaria denticulata

Pulmonates are air-breathing molluscs that do not include many families and genera [68]. Siphonaria species from many distinct geographical areas possess a series of secondary metabolites with polypropionate skeletons characterized by the presence of ketal, pyrone and furanone moieties [47]. A rigorous biosynthetic experiment [69] proved that Siphonaria denticulata is able to... 

Manker, D. C., Garson, M. J., and Faulkner, D. J., De novo biosynthesis of polypropionate metabolites in the marine pulmonate Siphonaria denticulata, J. Chem. Soc. Chem. Commun., 1061, 1988. 

Denticulatins A and B. The denticulatins A (250) and B (251) were isolated in 1983 from the marine mollusc Siphonaria denticulata and are highly oxygenated structures with seven contiguous stereocenters (Scheme 9-67). Three total syntheses of these molecules rely upon aldol reactions to assemble triketone 252. a key intermediate, forming either the Ciq-Ch or C9-C10 bond at a late stage. 

Denticulatins A and B 39 are one of several polyketide-based natural products that have been synthesized using a SAMP/RAMP hydrazone alkylation as a key step (Scheme 7.6A). The denticulatins are intriguing polypropionate metabolites isolated from Siphonaria denticulata, a class of air-breathing mollusks. Denticulatins A and B were first isolated from these mollusks in 1983 off the coast of... 

CarbaHeira, N.M., Cruz, H., Hill, C.A., De Voss, J.J., and Garson, M. (2001) Identification and total synthesis of novel fatty adds from the siphonarid limpet Siphonaria denticulata. J. Nat. Prod., 64, 1426-1429. 

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