Marine Sponge Dysidea Fragilis Research Articles

Minor Polybrominated Diphenyl Ethers from the Marine Sponge Dysidea fragilis

Minor Polybrominated Diphenyl Ethers from the Marine Sponge Dysidea fragilis

Two sesquiterpene aminoquinones protect against oxidative injury in HaCaT keratinocytes via activation of AMPKα/ERK-Nrf2/ARE/HO-1 signaling

AimsTo investigate the cytoprotective effects of two sesquiterpene aminoquinones isolated from the marine sponge Dysidea fragilis, Dysidaminone H (DA8) and 3′-methylamino-avarone (DA14), we examined their effects against hydrogen peroxide (H2O2)-induced oxidative injury in human keratinocyte cell line and elucidated the underlying mechanisms. Main methodsCell viability was detected using a CCK-8 assay kit. Intracellular reactive oxygen species (ROS) production was measured by fluorescence of 2, 7-Dichlorodi-hydrofluorescein diacetate (DCFH-DA). Messenger RNA and protein expression were measured by real-time quantitative PCR and western blotting analysis. Immunocytochemistry was performed to determine the intracellular location of nuclear factorerythroid 2 p45 related factor 2 (Nrf2). The antioxidant response element (ARE)-luciferase reporter gene assay and RNA interference were used to establish the role of ARE and Nrf2. Key findingsDA8 and DA14 (DAs) resisted H2O2induced decline of cell viability by inhibiting the accumulation of ROS. Meanwhile, DAs increased HO-1 expression and ARE activity and induced Nrf2 expression, as well as the accumulation of Nrf2 in the cell nucleus. However, silencing of Nrf2 abolished DAs-induced HO-1 expression and ARE luciferase activation. In addition, DAs induced the phosphorylation of both cyclic AMP-activated protein kinase-α (AMPKα) and extracellular signal-regulated kinase (ERK), while specific inhibitors of AMPKα and ERK abrogated HO1 upregulation and Nrf2 activation. SignificanceDAs provided cytoprotective effects against H2O2-induced cytotoxicity by activation of the Nrf2/ARE/HO-1 pathway via phosphorylation of AMPKα and ERK. The findings suggested that DA8 and DA14 might be the candidate therapeutic agents for skin diseases caused by oxidative injury.

Bis-sesquiterpene from the Marine Sponge Dysidea fragilis

Two new sesquiterpenes and one new bis-sesquiterpene, named dysinidins C-E (1-3) along with three known sterols, dysideasterol F, 9α,l lα-epoxycholest-7-en-3β,5α,6α-triol, and 9α,11α-epoxycholest-7-en-3β,5α,6α,19-tetrol 6-acetate (4-6) were isolated from the Vietnamese marine sponge Dysidea fragilis (Montagu, 1814). Their structures were determined by 1D- and 2D-NMR spectroscopies and HR-ESI-MS, as well as by comparison with reported literature data. Compounds 4-6 were found to inhibit eight human cancer cell lines (KB, LU-1, HL-60, LNCaP, SK-Mel-2, HepG-2, MCF-7, and PC-3), with IC50 values ranging from 7.3 to 31.5 µM.

Sesquiterpenes from the Vietnamese Marine Sponge Dysidea Fragilis

Two new sesquiterpenes, named dysinidins A-B (3, 4) along with two known sesquiterpenes, furodysinin lactone (1) and O-methyl urodysinin lactone (2), were isolated from the Vietnamese marine sponge Dysidea fragilis. Their structures were determined by ID- and 2D-NMR spectroscopies and HR ESI MS, as well as by comparison with reported literature data. None of compounds showed inhibitory growth of human lung cancer cell lines, A-549 and H-1975 (IC50 > 30 μM).

ChemInform Abstract: Dysifragilones A—C, Unusual Sesquiterpene Aminoquinones and Inhibitors of NO Production from the South China Sea Sponge Dysidea fragilis.

AbstractThree unusual sesquiterpene aminoquinones based on a rearranged avarone skeleton, dysifragilones A (Ia), B (Ib), and C (II), are isolated from the marine sponge Dysidea fragilis.

ChemInform Abstract: Two New Unprecedented Acetonyl‐Bearing Sesquiterpenes from the Hainan Sponge Dysidea fragilis.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Two New Unprecedented Acetonyl‐Bearing Sesquiterpenes from the Hainan Sponge Dysidea fragilis

Two new acetonyl-bearing sesquiterpenes, dysifragilisins A and B (1 and 2, resp.), have been isolated from the Hainan marine sponge Dysidea fragilis. The structures of the new compounds were elucidated on the basis of detailed spectroscopic analyses and by comparison of their NMR data with those of structurally related compounds. A plausible biogenetic pathway is proposed for the origin of compounds 1 and 2.

A new spiro-sesquiterpene from the sponge Dysidea fragilis

A new spiro-sesquiterpene, spirofragilin (1), along with a known related sesquiterpene, dehydroherbadysidolide (2), have been isolated from the marine sponge Dysidea fragilis collected in the South China Sea. The structure of 1 was elucidated on the basis of detailed spectroscopic analysis.

Exploiting 2-Halo-2H-Azirine Chemistry

H-Azirines are the smallest unsaturated heterocyclic compounds containing nitrogen. Despite their strain many stable azirines are known. Due to the high reactivity 2H-azirines have been explored extensively for various synthetic purposes. The ring system occurs naturally in the antibiotics azirinomycin, isolated from Streptomyces auras cultures. Moreover, both enantiomers of (R)-(+)- and (S)-(-)-dysidazirine and (S)-(+)- antazirine were isolated from the marine sponge Dysidea fragilis. The chemistry of 2H-azirines is dominated by ring strain and processes in which the strain is relieved are very favoured. 2H -Azirines undergo reactions in which they can function either as a nucleophile or as an electrophile. They can participate in cycloadditions as 2π -components and undergo ring cleavage on photochemical excitation to give nitrile ylides which can act as 4π -component in dipolar cycloadditions. Thermal ring cleavage originates vinyl nitrenes which allows for ring expansion reactions. X-Ray crystallographic structure determinations reported to highly substituted 2H-azirines indicate an unusually long C2-N bond explaining the preferential C2-N cleavage in thermal reactions of 2H-azirines. The photolysis of azirines bearing a conjugative substituent (e.g. phenyl, vinyl) at C-2 leads to nitrile ylides with conjugative groups which can participate in 1,5-dipolar electrocyclic ring closure. The study of the reactivity of 2-halo-2H-azirines is of particular interest since this system bears an extra functional group.

A furodysinin lactone derivative from the marine spongeDysidea fragilis

The title compound, 4a,5,6,8a,9,9a-hexahydro-9a-hydroxy-4,4,7-trimethylnaphtho[2,3-b]furan-2(4H)-one, C15H20O3, is a sesquiterpenoid isolated from the marine sponge Dysidea fragilis. The furodysinin lactone skeleton consists of two six-membered rings, which adopt chair and half-chair conformations, and a furan ring. The mol­ecules are arranged in a helical pattern through O—H⋯O hydrogen bonds.

Anatomical and ultrastructural studies of chemical defence in the sponge Dysidea fragilis

The marine sponge Dysidea fragilis from El Mar Menor, a hypersaline coastal lagoon (Murcia, Spain), contains the furanosesquiterpenoid ent-furodysinin as the major secondary metabolite. D. fragilis emits a defensive white fluid when it is disturbed. Electron micrographs of this fluid revealed intact vesiculated cells together with other amorphous material. Dissociated cells are more rounded in shape but maintain the same ultrastructural features as cells observed in ultra-thin sections of the whole sponge. The defensive secretion is composed mainly of sponge cells with abundant light vesicles. Sometimes these light vesicles appear to open into the intercellular space; this correlates with surface blebs on these cells observed under scanning electron microscopy. The intracellular location of ent-furodysinin was confirmed by Erlich staining. In laboratory assays, we examined the role of ent-furodysinin as a feeding deterrent to generalist fish predators. It was isolated from D. fragilis and incorporated into a carrageenan-based artificial diet. The addition of ent-furodysinin to the artificial diet reduced feeding by the fish Thalassoma pavo. Similarly, fish did not feed on artificial diet above which defensive secretion of D. fragilis had been ejected with a small syringe.

A New Diketopiperazine Derivative from the South China Sea SpongeDysideafragilis

A new diketopiperazine, dysamide D (1), has been isolated from the marine sponge Dysidea fragilis, collected in the South China Sea. The structure of dysamide D was determined by spectral data.

Crystal structure of the complex of brominated diphenyl ethers from the marine spongeDysidea fragilis

The spatial structures of 2-(2′,4′-dibromophenoxy)-3,4,5-tribromophenoI (1) and 2-(2′-hydroxy-4′,6′-dibromophenoxy)-4,6-dibromoanisole (2) in crystals of the complex formed through two intermolecular O-H-O bonds were determined. The conformations of both molecules were found to be stabilized by intermolecular hydrogen bonds. The external hydrophobic surface of the complex of two molecules was shown to be occupied by nine bromine atoms.

New cytotoxic steroids from the marine sponge Dysidea fragilis coming from the lagoon of Venice

The sterol composition of the sponge Dysidea fragilis, coming from the lagoon of Venice, has been investigated; our results confirmed the variability of D. fragilis biochemistry. The sponge elaborates, in addition to eight usual 3β-hydroxy sterols, thirteen polyhydroxysterols, eight of them ( 6–13) were novel compounds. Their structures were established by spectroscopic data. New compounds 3β,5α,6β,7α-tetrahydroxy-cholest-8(9)-en-11-one ( 8), 3β,5α,6α-trihydroxy-9,11-secocholest-7-en-9-one ( 9) and 3β,5α,6α,9α-tetrahydroxy-cholest-7-ene-6-sulfate ( 11) were proved to be cytotoxic on two different tumor cell lines in vitro.

Three New Diketopiperazines from a Marine Sponge Dysidea fragilis

Three new polychlorinated diketopipeeazines, dysamides A [1], B [2], and C [3], and the known compound 4 have been isolated from a marine sponge Dysidea fragilis collected off Hainan Island. Their structures were established by spectroscopic methods, and complete nmr assignments were made. The absolute configuration and conformation of 1 were determined by X-ray crystallographic diffraction analysis

Brominated diphenyl ethers from the marine sponge Dysidea fragilis

Brominated diphenyl ethers from the marine sponge Dysidea fragilis

Penlanfuran, a new furanoid sesquiterpene from the marine sponge [formula omitted][formula omitted] (mont.) of Brittany. A striking difference with the same Hawaiian species.

Penlanfuran ( 2 ), a furanoid sesquiterpene with a novel skeleton for sponge products, has been afforded by the marine sponge Dysidea fragilis (Mont.) of Brittany; the same Hawaiian species gave different sesquiterpenoids.

Two Furanosesquiterpene Marine Metabolites with Antifeedant Properties

AbstractTwo new sesquiterpenoids, nakafuran‐8 (1) and −9 (8), have been isolated from the marine sponge Dysidea fragilis and from its prey, the nudibranchs Hypselodoris godeffroyana and Chromodoris maridadilus. The structures were established by spectral analysis and chemical transformations. Both compounds possess antifeedant properties when assayed in the laboratory against common reef fishes, Chaetodon spp.