Renieramide, a cyclic tripeptide from the Vanuatu sponge Reniera n. sp.
The polar extract of the Vanuatu sponge Reniera n. sp., which showed immunomodulating activity in preliminary tests, was found to contain a cyclic tripeptide, which we named renieramide (1). This metabolite is identical to a synthetic derivative mentioned in a patent concerning the preparation of cyclic peptides of the OF4949 family of anticancer agents. We describe here the first isolation of this metabolite from natural sources and its complete characterization by spectroscopic and chemical approaches. Renieramide (1) possesses a 17-membered cyclic side-chain-linked biphenyl ether skeleton, typical of the class that includes the natural products OF4949 I-IV, K13, and eurypamides. A tridimensional model of 1, obtained by NMR restrained molecular mechanics and dynamics, is also presented.
Ciasullo
Linda
L
Dipartimento di Scienze Farmaceutiche, Università di Salerno, 84084 Fisciano (SA), Italy.
Casapullo
Agostino
A
Cutignano
Adele
A
Bifulco
Giuseppe
G
Debitus
Cécile
C
Hooper
John
J
Gomez-Paloma
Luigi
L
Riccio
Raffaele
R
D000276:Adjuvants, Immunologic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000818:Animals; D008958:Models, Molecular; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010456:Peptides, Cyclic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D011161:Porifera / Q000737:chemistry*; D013055:Spectrophotometry, Infrared
D000276:Adjuvants, Immunologic; D010456:Peptides, Cyclic; C456052:renieramide