A New Cembranolide from the Soft Coral Sinularia capillosa

Abstract

A new cembranolide, capillolide (1), and three known cembranolides were isolated from the soft coral Sinularia capillosa collected from the South China Sea. Their structures and the relative stereochemistry of 1 were deduced on the basis of spectroscopic methods.

Structural Elucidation and Structure–Anti-inflammatory Activity Relationships of Cembranoids from Cultured Soft Corals Sinularia sandensis and Sinularia flexibilis

“…The structure and absolute stereochemistry of 9 were also confirmed by single-crystal X-ray diffraction ( Figure 2) with Cu Kα irradiation [Flack parameter of 0.09 (3)] (CCDC 1044093). On the basis of the results presented above, compound 9 was established as (1R,4R,5R,13S,8E,11Z)-5-acetoxy-13-hydroxy-cembr-8(9),11 (12),15(17)-trien-16,4-olide In addition, the 11 known compounds obtained were identified as sinumaximol B (3), 17 pukalide (4), 21 10-epigyrosanoldie E (5), 14,15 diepoxycembrene A (7), 17 sinulaflexiolide K (10), 22 (−)-sandensolide (11), 23 11-dehydrosinulariolide (12), 24 sinulariolide (13), 25 3,4:8,11-bisepoxy-7-acetoxycembra-15(17)-en-1,12-olide (14), 26 dendronpholide F (15), 27 and dendronpholide G (16) 24 by comparison of spectroscopic data with published values. The absolute configurations of 4 and 15 were confirmed by single-crystal X-ray diffraction analysis with Cu Kα radiation [Flack parameters of 0.12(5) and 0.14(8), respectively] for the first time ( Figure 2).…”

Oxygenated Cembranoids from the Cultured and Wild-Type Soft Corals Sinularia flexibilis

“…Some of these were found to exhibit cytotoxic activity against the growth of various cancer cell lines. 1,[3][4][5][6][10][11][12] During the course of our investigation on new natural substances from the cultured and wild-type soft corals S. flexibilis, four new cembranoids (1-4) along with two known metabolites, 11-epi-sinulariolide acetate (5) 12,18) and sinulariolide (6) 1,19) have been isolated. New metabolites flexibilisolide A (1) and flexibilisin A (2) were isolated from the cultured soft coral, and flexibilisolide B (3) and flexibilisin B (4) were obtained from the wild-type soft coral.…”

Sinuladiterpenes A–F, New Cembrane Diterpenes from Sinularia flexibilis

“…IR (n max in cm À 1 ) and UV spectra: Hitachi T-2001 and Hitachi U-3210 spectrophotometers, resp. 1 H-, 13 C-NMR, COSY, HMQC, HMBC, and NOESY spectra: Bruker FT-300 spectrometer or Varian Unity INOVA 500 FT-NMR at 500 MHz for 1 H and 125 MHz for 13 C, resp., TMS as internal standard; the chemical shifts d are given in ppm and coupling constants J in Hz. Low-resolution EI-MS and FAB-MS: VG Quattro 5022 mass spectrometer.…”

“…The downfield-shift signal of an Obearing quaternary C-atom at d(C) 90.0 was assigned to C (12), suggesting 16,12-lactonization, thus forming a seven-membered lactone ring (e-lactone) [13]. The Me (18) (HÀC(7))), suggesting the presence of a C(6)¼C(7) bond, which was verified by a HMBC between HÀC(7)/C(5).…”