Calyculaglycosides D and E, novel cembrane glycosides from the Caribbean gorgonian octocoral Eunicea species and structural revision of the aglycon of calyculaglycosides A-C.
A recent investigation of the constituents of Eunicea sp. from Colombia and Puerto Rico has provided two novel cembrane glycosides, calyculaglycosides D (6) and E (7), and a new cembranoid diterpene in free form, (+)-nephthenol (4). Metabolites 6 and 7 possess a glycosyl-fused cembrane skeleton with a 1S configuration. Biogenetic considerations have led to a revision of the previously assigned dilophol skeleton of calyculaglycosides A-C, which was confirmed by extensive 2D NMR investigation and a chemical degradation study. Consequently, the true structures for calyculaglycosides A-C are 8-10, respectively, not 1-3. This is the first report of the occurrence of marine diterpene glycosides having a cembrane aglycon.
Shi
Y P
YP
Department of Chemistry, University of Puerto Rico, P.O. Box 23346, San Juan, Puerto Rico 00931-3346, USA.
Rodríguez
A D
AD
Padilla
O L
OL
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003063:Cnidaria / Q000737:chemistry*; D003105:Colombia; D004224:Diterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D008401:Gas Chromatography-Mass Spectrometry; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D011647:Puerto Rico; D013055:Spectrophotometry, Infrared; D013237:Stereoisomerism
D004224:Diterpenes; D006027:Glycosides; C442769:calyculaglycoside D; C442770:calyculaglycoside E; C037071:cembrane