9 research outputs found
Eunicellin-Based Diterpenoids from the Formosan Soft Coral <i>Klyxum molle</i> with Inhibitory Activity on Superoxide Generation and Elastase Release by Neutrophils
Eleven new eunicellin-based diterpenoids
possessing a cladiellane
skeleton with a C-2, C-9 ether bridge, klymollins I–S (<b>1</b>–<b>11</b>), have been isolated from the EtOAc
extract of the soft coral <i>Klyxum molle</i> from Taiwan
waters. The structures of compounds <b>1</b>–<b>11</b> were elucidated by extensive spectroscopic analysis, including 2D
NMR spectroscopy (COSY, HSQC, HMBC, and NOESY). Compound <b>5</b> exhibited cytotoxicity toward several cancer cell lines. Compound <b>5</b> is the first eunicellin-based metabolite bearing a phenyl
group and displays significant inhibition of both superoxide anion
generation and elastase release in <i>N</i>-formyl-methionyl-leucyl-phenylalanine/cytochalasin
B (fMLP/CB)-induced human neutrophils
Structural Elucidation and Structure–Anti-inflammatory Activity Relationships of Cembranoids from Cultured Soft Corals <i>Sinularia sandensis</i> and <i>Sinularia flexibilis</i>
New
cembranoids 4-carbomethoxyl-10-epigyrosanoldie E (<b>1</b>),
7-acetylsinumaximol B (<b>2</b>), diepoxycembrene B (<b>6</b>), dihydromanaarenolide I (<b>8</b>), and isosinulaflexiolide
K (<b>9</b>), along with 11 known related metabolites, were
isolated from cultured soft corals <i>Sinularia sandensis</i> and <i>Sinularia flexibilis</i>. The structures were elucidated
by means of infrared, mass spectrometry,
and nuclear magnetic resonance techniques, and the absolute configurations
of <b>1</b>, <b>4</b>, <b>9</b>, and <b>15</b> were further confirmed by single-crystal X-ray diffraction analysis.
The absolute configurations of these coral metabolites and comparison
with known analogues showed that one hypothesis (that cembrane diterpenes
possessing an absolute configuration of an isopropyl group at C1 obtained
from Alcyonacean soft corals belong to the α series, whereas
analogues isolated from Gorgonacean corals
belong to the β series) is not applicable for a small number
of cembranoids. An <i>in vitro</i> anti-inflammatory study
using LPS-stimulated macrophage-like
cell line RAW 264.7 revealed that compounds <b>9–14</b> significantly suppressed the accumulation of pro-inflammatory
proteins, iNOS and COX-2. Structure–activity relationship analysis
indicated that cembrane-type compounds with
one seven-membered lactone moiety at C-1 are potential anti-inflammatory
agents. This is the first culture system in the world that has successfully
been used to farm <i>S. sandensis</i>
Halogenated Sesquiterpenoids from the Red Alga <i>Laurencia tristicha</i> Collected in Taiwan
Chemical investigation of the red
alga <i>Laurencia tristicha</i> led to the discovery of
eight new halogenated chamigrane-type sesquiterpenoids
(<b>1</b>–<b>8</b>) and one new bromocuparane-type
sesquiterpene (<b>9</b>), along with nine known related metabolites
(<b>10</b>–<b>18</b>). Their structures were elucidated
on the basis of extensive spectroscopic analyses, and the absolute
configurations of <b>1</b>–<b>8</b> were proposed
by comparison to the biosynthetically related known compound <b>12</b>. Cytotoxicity, antibacterial, and anti-inflammatory activities of these isolates
were also investigated. The results showed that compound <b>11</b> exhibited good antibacterial activity against <i>Serratia marcescens</i> compared to the positive control ampicillin at a dosage of 100 μg/disk.
Compound <b>17</b> showed strong inhibition toward elastase
release generation at 10 μM
Halogenated Sesquiterpenoids from the Red Alga <i>Laurencia tristicha</i> Collected in Taiwan
Chemical investigation of the red
alga <i>Laurencia tristicha</i> led to the discovery of
eight new halogenated chamigrane-type sesquiterpenoids
(<b>1</b>–<b>8</b>) and one new bromocuparane-type
sesquiterpene (<b>9</b>), along with nine known related metabolites
(<b>10</b>–<b>18</b>). Their structures were elucidated
on the basis of extensive spectroscopic analyses, and the absolute
configurations of <b>1</b>–<b>8</b> were proposed
by comparison to the biosynthetically related known compound <b>12</b>. Cytotoxicity, antibacterial, and anti-inflammatory activities of these isolates
were also investigated. The results showed that compound <b>11</b> exhibited good antibacterial activity against <i>Serratia marcescens</i> compared to the positive control ampicillin at a dosage of 100 μg/disk.
Compound <b>17</b> showed strong inhibition toward elastase
release generation at 10 μM
New Meroterpenoids from <i>Aspergillus terreus</i> with Inhibition of Cyclooxygenase‑2 Expression
Two novel meroterpenoids,
yaminterritrems A (<b>1</b>) and
B (<b>2</b>), were isolated from <i>Aspergillus terreus</i> collected from hot spring zones in Yang-Ming Mountain, Taiwan, and
cultured at 40 °C. The structures of <b>1</b> and <b>2</b> were elucidated by NMR, MS spectral and X-ray crystallographic
analyses. The biosynthetic route for <b>1</b> and <b>2</b> involving the conversion of the sesquiterpene with phenyl-α-pyrone
is proposed. Besides, <b>2</b> exhibited a dose-dependent inhibitory
effect on COX-2 expression in LPS-stimulated RAW264.7 macrophages
Bioactive Isoprenoid-Derived Natural Products from a Dongsha Atoll Soft Coral Sinularia erecta
Four new isoprenoids, including two
norcembranoids sinulerectols
A and B (<b>1</b> and <b>2</b>), a cembranoid sinulerectol
C (<b>3</b>), and a degraded cembranoid sinulerectadione (<b>4</b>), along with three known isoprenoids, an unnamed norcembrene
(<b>5</b>), sinularectin (<b>6</b>), and ineleganolide
(<b>7</b>), and a known nitrogen-containing compound (<i>Z</i>)-<i>N</i>-[2-(4-hydroxyphenyl)Âethyl]-3-methyldodec-2-enamide
(<b>8</b>), were isolated from an extract of the marine soft
coral Sinularia erecta. The structure
of sinularectin (<b>6</b>) was revised, too. Compounds <b>3</b>, <b>4</b>, and <b>8</b> exhibited inhibitory
activity against the proliferation of a limited panel of cancer cell
lines, whereas <b>1</b>, <b>2</b>, and <b>8</b> displayed
potent anti-inflammatory activity in fMLP/CB-stimulated human neutrophils
Withanolide-Based Steroids from the Cultured Soft Coral <i>Sinularia brassica</i>
Seven novel withanolides, sinubrasolides
A–G (<b>1</b>–<b>7</b>), have been isolated
from the cultured soft
coral <i>Sinularia brassica</i>. The structures of the new
metabolites were determined by extensive spectroscopic analyses, and
the absolute configuration of <b>1</b> was established by X-ray
crystallographic analysis. The cytotoxicities of compounds <b>1</b>–<b>7</b> against a limited panel of cancer cell lines
also were determined
Withanolide-Based Steroids from the Cultured Soft Coral <i>Sinularia brassica</i>
Seven novel withanolides, sinubrasolides
A–G (<b>1</b>–<b>7</b>), have been isolated
from the cultured soft
coral <i>Sinularia brassica</i>. The structures of the new
metabolites were determined by extensive spectroscopic analyses, and
the absolute configuration of <b>1</b> was established by X-ray
crystallographic analysis. The cytotoxicities of compounds <b>1</b>–<b>7</b> against a limited panel of cancer cell lines
also were determined
A Soft Coral-Derived Compound, 11-<i>epi</i>-Sinulariolide Acetate Suppresses Inflammatory Response and Bone Destruction in Adjuvant-Induced Arthritis
<div><p>In recent years, a significant number of metabolites with potent anti-inflammatory properties have been discovered from marine organisms, and several of these compounds are now under clinical trials. In the present study, we isolated 11-<i>epi</i>-sinulariolide acetate (Ya-s11), a cembrane-type compound with anti-inflammatory effects, from the Formosa soft coral <i>Sinularia querciformis</i>. Preliminary screening revealed that Ya-s11 significantly inhibited the expression of the proinflammatory proteins induced nitric oxide synthase and cyclooxygenase-2 in lipopolysaccharide-stimulated murine macrophages. We also examined the therapeutic effects of Ya-s11 on adjuvant-induced arthritis (AIA) in female Lewis rats, which demonstrate features similar to human rheumatoid arthritis (RA). Animal experiments revealed that Ya-s11 (subcutaneously 9 mg/kg once every 2 days from day 7 to day 28 postimmunization) significantly inhibited AIA characteristics. Moreover, Ya-s11 also attenuated protein expression of cathepsin K, matrix metalloproteinases-9 (MMP-9), tartrate-resistant acid phosphatase (TRAP), and tumor necrosis factor-α (TNF-α) in ankle tissues of AIA-rats. Based on its attenuation of the expression of proinflammatory proteins and disease progression in AIA rats, the marine-derived compound Ya-s11 may serve as a useful therapeutic agent for the treatment of RA.</p></div