Sinuhirtone A, An Uncommon 17,19-Dinorxeniaphyllanoid, and Nine Related New Terpenoids from the Hainan Soft Coral Sinularia hirta.

Chemical investigation of the Hainan soft coral Sinularia hirta resulted in the isolation and identification of a library of sixteen structurally diverse terpenoids, including a dinorditerpenoid with an uncommon 17,19-dinorxeniaphyllane skeleton, namely sinuhirtone A (7), six new xeniaphyllane-type diterpenoids (1-6), one new norxeniaphyllanoid (8), two new norcaryophyllene-type sesquiterpenoids (9 and 10), together with six known related compounds (11-16). Compounds 1-3 are three new furanone-containing xeniaphyllane-type diterpenoids. The structures of the new compounds, including their absolute configurations, were determined by extensive spectroscopic analysis and a series of quantum chemical calculations, including quantum mechanical-nuclear magnetic resonance (QM-NMR), time-dependent density functional theory-electronic circular dichroism (TDDFT-ECD), and optical rotatory dispersion (ORD) methods. A plausible biosynthetic connection between new compounds 1-9 was also proposed. New compounds 2-4, 7, and 8 were evaluated for in vitro cytotoxicity against four cancer cell lines.

Spongian diterpenes from Chinese marine sponge Spongia officinalis.

3-Nor-spongiolide A (1), belonging to the extremely rare 3-nor-spongian carbon skeleton, and spongiolides A (2) and B (3), having γ-butenolide instead of furan ring as usual for ring D, together with six related known metabolites were isolated from South China Sea sponge Spongia officinalis as its metabolic components. Their structures were elucidated on the basis of extensive spectroscopic analysis. The absolute configurations of three new compounds 1-3 were determined by ECD calculations.

Asymmetric Total Synthesis of Distaminolyne A and Revision of Its Absolute Configuration.

The first total synthesis of a marine derived polyacetylene, distaminolyne A, and its enantiomer were achieved from the commercially available undec-10-en-1-ol. A key proline-catalyzed asymmetric α-aminooxylation of an aldehyde intermediate was used to introduce the chiral center en route to the enantiomerically pure 1,2-amino alcohols. The absolute configuration of both synthesized enantiomers of distaminolyne A was confirmed by using chiral derivatizing agents, leading to revision of the natural product absolute configuration from 2S to 2R. Antibacterial, pancreatic lipase (PL) inhibitory, and protein-tyrosine phosphatase 1B (PTP1B) inhibitory activities were evaluated.

[Effect of ray cartilage glycosaminoglycans (RCG) on the expression of MMP-9 in Lewis lung carcinoma].

OBJECTIVE: To explore the effect of Ray cartilage glycosaminoglycans (RCG) on the expression of MMP-9 in Lewis lung carcinoma of mice. METHOD: The model of mice with Lewis lung carcinoma was induced. The experimental mice were randomly divided into normal saline group, RCG groups at varied concentrations and CTX group. Tumor growth state was observed, and tumor inhibitory rate of primary tumor and number of lung metastasis focus were measured. The expression of MMP-9 mRNA and protein in Lewis lung carcinoma was determined with RT-PCR and Western blot. RESULT: As compared with normal saline group, tumor growth curves in RCG groups were smooth, there were significant differences of inhibitory rates of primary tumor and number of lung metastasis focus between RCG groups and normal saline group, and MMP-9 mRNA and protein expression levels in RCG groups were reduced significantly. CONCLUSION: RCG can inhibit effectively the growth and metastasis of implanted Lewis lung carcinoma in C57BL/6 mice, which is probably attributed to reducing the expression of MMP-9 mRNA and protein.

Further casbane-type diterpenes from the soft coral Sinularia depressa.

AIM: To study the minor diterpenes from the soft coral Sinularia depressa METHOD: The chemical constituents were isolated and purified by various chromatographic techniques, and the chemical structures, including absolute configuration, were established on the basis of detailed analysis of spectroscopic data and by literature comparison with the data of related known compounds. RESULTS: A new casbane-type diterpene, 2-epi-10-hydroxydepressin (1), was isolated and identified. CONCLUSION: Compound 1 is a new casbane-type diterpene.

[Comparison study on knee osteoarthritis in rabbits induced by different concentrations of papain].

OBJECTIVE: To compare the knee osteoarthritis (OA) models in rabbits by different concentrations of papain and provide data for exploring pathogenesis and treatments of this disease. METHODS: Sixty New Zealand white rabbits were randomly divided into four groups of 15 each and given injections into the right knee on days 1, 3 and 5 including intra-articular injections of 2%, 5% or 10% (w/v) papain and 0.03 mol/L L-cysteine at the dose of 0.1 ml/kg (experimental groups). The 0.9% NaCl (w/v) with a dose of 0.1 ml/kg were injected intra-articularly into the right knees of rabbits in the control group. The rabbits were sacrificed at 2, 4, 6 weeks respectively after the initiation of papain injection and these OA models were evaluated through recording the width of knee joint, performing the morphological observation and histological evaluation of articular cartilage and synovium. RESULTS: The degenerative changes were demonstrated in knee joints of rabbit in all experimental groups, such as thinner articular cartilage, fibrillation and destroyed cartilage matrix, and inflammation, proliferation, and degeneration of the synovial tissue. All these changes were much worse with increased concentration and prolonged observation time. CONCLUSION: Different severity of OA are established through intra-articular injections of 2%, 5% or 10% papain and 0.03 mol/L L-cysteine at the dose of 0.1 ml/kg. These models are of the characters of short period and a good reproducibility.