New γ-pyrone propionates from the Indian Ocean sacoglossan Placobranchus ocellatus

• Published in: Tetrahedron letters Vol. 46; no. 3; pp. 465 - 468
• Main Authors: Manzo, Emiliano, Ciavatta, Maria Letizia, Gavagnin, Margherita, Mollo, Ernesto, Wahidulla, Solimabi, Cimino, Guido
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 17.01.2005; Elsevier
• Subjects: Bicyclo octane; Chemistry; Chemistry, Organic; Physical Sciences; Placobronchus ocellatus; Sacoglossan; Science & Technology; γ-Pyrone propionates; Placobronchus ocellatus; γ-Pyrone propionates; Bicyclo octane; Sacoglossan; METABOLITES; MARINE MOLLUSKS; sacoglossan; Placobranchus ocellatus; gamma-pyrone propionates; TRIDACHIA-CRISPATA; bicyclo octane
• ISSN: 0040-4039; 1873-3581
• DOI: 10.1016/j.tetlet.2004.11.085

Two new γ-pyrone propionates (i.e., 9 , relative stereochemistry), characterised by a bicyclo [4.2.0] octane ring, have been isolated from the Indian sacoglossan Placobranchus ocellatus. A sunscreen protective role of compound 9 could be suggested by analogy with photodeoxytridachione previously found in the same mollusc. A new γ-pyrone propionate, compound 9 , and its peroxy derivative 10 have been isolated from the sacoglossan Placobranchus ocellatus. The structure and the relative stereochemistry of the new molecules, which displayed an unprecedented carbon skeleton characterised by a bicyclo [4.2.0] octane, have been determined by both spectroscopic methods and comparison with model compounds. By analogy with photodeoxytridachione ( 2 ), a sunscreen protective role could be also suggested for compound 9 in living P. ocellatus.