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Abstract Three new diterpenoids with an unusual capnosane skeleton named lobophytrols A–C (1 – 3) were isolated from the South China Sea soft coral Lobophytum sp. along with one known related diterpene, (11 S ,12 S ,1 E ,3 E ,7 E)-11,12-epoxycembra-1,3,7-triene (7). Their structures were elucidated on the basis of spectroscopic analysis and by comparison with those reported in the literature. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Three novel structures were isolated and identified from soft coral Sinularia flexibilis. • The cembranoids from S. flexibilis in South China Sea showed great chemical diversity. • Several cembranoids exhibited strong anti-inflammatory effect and cytotoxicity. Abstract Different chemotypes of Sinularia flexibilis exist in the Hainan island. Thus, a collection of this soft coral from a location different from the one of our previous study afforded three novel cembranoid esters featuring a n -butyl alcohol moiety, a structural element rare in natural products of both terrestrial and marine origin. The structures of the new compounds were elucidated by detailed spectroscopic analysis and by the comparison of their spectroscopic data with those reported in the literature. In addition, the absolute stereochemistry of the previously reported diepoxycembrene (9) was first time determined by the X-ray diffraction analysis. In bioassays, compounds 6 – 8 exhibited strong anti-inflammatory effect with IC 50 values of 2.7, 4.7, and 4.2 μM, respectively, whereas compound 5 displayed cytotoxicity against several cancer cells with IC 50 values ranging from 8.9 to 27.4 μM. A preliminary structural-activity relationship (SAR) was also described. [ABSTRACT FROM AUTHOR]

Four new uncommon nitrogenous eudesmane-type sesquiterpenes, axiriabilines A−D ( 1 – 4 ), and two known related ones ( 5 and 6 ), were isolated from the Hainan sponge Axinyssa variabilis . The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis and by comparison of their NMR data with those reported in the literature. The absolute configurations of compounds 1 and 4 were determined by TDDFT ECD calculations. All the new compounds were found to exhibit no cytotoxicity against several cancer cells. [ABSTRACT FROM AUTHOR]

Covering: 2011–2021 Marine mollusks, which are well known as rich sources of diverse and biologically active natural products, have attracted significant attention from researchers due to their chemical and pharmacological properties. The occurrence of some of these marine mollusk-derived natural products in their preys, predators, and associated microorganisms has also gained interest in chemical ecology research. Based on previous reviews, herein, we present a comprehensive summary of the recent advances of interesting secondary metabolites from marine mollusks, focusing on their structural features, possible chemo-ecological significance, and promising biological activities, covering the literature from 2011 to 2021. [ABSTRACT FROM AUTHOR]

Covering: 1960 to present This review summarizes the state-of-the-art on the use of transition metals in synthetic steps inspired by biosynthesis. After an introduction showing the importance of metals in life processes, with special emphasis on biosynthetic processes, their place in biomimetic synthesis will be described. Topics include oxidative cyclizations for polyether synthesis, electrophilic and radical cyclizations of polyprenoids, the role of palladium in electrocyclizations, oxidative biaryl couplings and other rearrangement steps. [ABSTRACT FROM AUTHOR]

A bio-inspired strategy was used to complete the formal synthesis of the antitubercular hirsutellone B and congeners A and C, through construction of its decahydrofluorene core from a linear polyene strand activated at both ends by a silyl enol ether and an allyl acetate. Our synthesis features a key electrophilic cyclization, starting with the remote activation (by [Yb(OTf)3] or BF3 ⋅OEt2) of the allyl acetate and stereoselectively affording the C ring. This was followed by an intramolecular Diels-Alder reaction to get the tricyclic core of the natural product. The stereoselective reduction of the resulting ketone towards the formal intermediate was critical to the success of this strategy. [ABSTRACT FROM AUTHOR]

Abstract: Four new (1–4) and 13 known (5–17) sesquiterpene lactones along with two known diterpenes (18, 19) were isolated from the whole plant of Carpesium faberi. The new structures were elucidated by means of spectroscopic techniques and some chemical transformations to be pseudoguaian-1α(H)-8α,12-olide-4β-O-β-d-glucopyranoside (1), 4β,10α-dihydroxy-5α(H)-1,11(13)-guaidien-8α,12-olide (2), 4β,10β-dihydroxy-5α(H)-1, 11(13)-guaidien-8β,12-olide (3), and (4S)-acetyloxyl-11(13)-carabren-8β,12-olide (4). All isolates were tested against MCF-7 human breast cancer cells using the MTT assay. Among them, the sesquiterpene lactones (except tomentosin 17) possessing an α-methylene-γ-lactone moiety were found to have in vitro antiproliferative activities, with IC50 values of 3.0–38.8μg/mL. The effects of four selected sesquiterpene lactones (guaianolide 2, carabranolide 4, pseudoguaianolide 9, eudesmanolide 13) on the cell cycle were examined using flow cytometry (FCM). [Copyright &y& Elsevier]

Three new dammarane-type triterpene ginsenosides, together with six known ginsenosides, were isolated from the leaves of Panax ginseng C.A. Meyer. The new saponins were named as ginsenoside Rh11, ginsenoside Rh12, and ginsenoside Rh13. Their structures were elucidated as (20S)-3β,6α,12β,20-tetrahydroxydammara-25-ene-24-one 20-O-β-d-glucopyranoside (1), (20S)-3β,12β,20,24,25-pentahydroxydammarane 20-O-β-d-glucopyranoside (2), and (20S,23E)-3β,12β,20,25-tetrahydroxydammara-23-ene 20-O-β-d-glucopyranoside (3) on the basis of 1D and 2D NMR experiments and mass spectra. The known ginsenosides were identified as ginsenoside M7cd, ginsenoside Rg6, ginsenoside Rb3, gypenoside XVII, gypenoside IX, and 20-(E)-ginsenoside F4. [ABSTRACT FROM AUTHOR]

Abstract: Thirty-six naturally occurring compounds, including four C10-acetylenic glycosides and a lignan, were isolated from the whole plants of Saussurea cordifolia. Their structures were elucidated by means of spectroscopic and chemical methods to be 4,6-decadiyne-1-O-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside (1), 4,6-decadiyne-1-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (2), (8E)-decaene-4, 6-diyn-1-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (3), (8Z)-decaene-4,6-diyn-1-O-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside (4), and (2R,3S,4S)-4-(4-hydroxy-3-methoxybenzyl)-2-(5-hydroxy-3-methoxyphenyl)-3-(hydroxymethyl)-tetrahydrofuran-3-ol (5). [Copyright &y& Elsevier]

Introduction: Kamebakaurin is an active constituent of both Rabdosia japonica and Rabdosia excisa, which are utilized in Chinese traditional medicine for improving symptoms in patients with allergies. We investigated the molecular mechanisms of the anti-allergic effects of kamebakaurin using BMMCs. Methods: The degranulation ratio, histamine release, and the interleukin (IL)-4, leukotriene B4 (LTB4), and cysteinyl leukotriene productions on antigen-triggered BMMC were investigated. Additionally, the effects of kamebakaurin on signal transduction proteins were examined by Western blot and binding to the Syk and Lyn kinase domain was calculated. The effects of kamebakaurin on antigen-induced hyperpermeability were investigated using mouse model. Results: At 10 μm, kamebakaurin partially inhibited degranulation, histamine release, and IL-4 production. At 30 μm, kamebakaurin partially reduced LTB4 and cysteinyl leukotriene productions and suppressed degranulation, histamine release, and IL-4 production. Phosphorylation of both Syk Y519/520 and its downstream protein, Gab2, was reduced by kamebakaurin, and complete inhibition was observed with 30 μm kamebakaurin. In contrast, phosphorylation of Erk was only partially inhibited, even in the presence of 30 μm kamebakaurin. Syk Y519/520 is known to be auto-phosphorylated via intramolecular ATP present in its own ATP-binding site, and this auto-phosphorylation triggers degranulation, histamine release, and IL-4 production. Docking simulation study indicated kamebakaurin blocked ATP binding to the ATP-binding site in Syk. Therefore, inhibition of Syk auto-phosphorylation by kamebakaurin binding to the Syk ATP-binding site appeared to cause a reduction of histamine release and IL-4 production. Kamebakaurin inhibited antigen-induced vascular hyperpermeability in a dose-dependent fashion but did not reduce histamine-induced vascular hyperpermeability. Conclusion: Kamebakaurin ameliorates allergic symptoms via inhibition of Syk phosphorylation; thus, kamebakaurin could be a lead compound for the new anti-allergic drug. [ABSTRACT FROM AUTHOR]

• Two uncommon norhumulene-type terpenoids were isolated from the South China Sea soft coral Sinularia hirta. • Their structures were determined by 1D/2D NMR, ECD calculation and GIAO 13C NMR calculation. • A plausible biogenetic relationship of 1–4 was proposed. Two new uncommon norhumulene-type norsesquiterpenoids, namely sinuhirtins A (1) and B (2), along with two known norcaryophyllene-type norsesquiterpenoids (3 and 4), were isolated from the South China Sea soft coral Sinularia hirta. The structures and absolute configurations of the new compounds were determined by extensive spectroscopic data analyses, and computer-assisted methods including GIAO 13C NMR and TDDFT-ECD calculations. A plausible biogenetic relationship of 1 – 4 was proposed. [ABSTRACT FROM AUTHOR]

A detailed chemical investigation of the Sanya Bay nudibranch Hexabranchus sanguineus yielded thirteen new sesquiterpenoids, namely sanyagunins A−H, sanyalides A−C, and sanyalactams A and B, along with eleven known related ones. Sanyalactams A and B feature an unprecedented hexahydrospiro[indene‐2,3′‐pyrrolidine] core. The structures of new compounds were established by a combination of extensive spectroscopic data analysis, quantum mechanical‐nuclear magnetic resonance methods, the modified Mosher's method, and X‐ray diffraction analysis. Based on analysis of NOESY correlations and the modified Mosher's method, the stereochemistry of two known furodysinane‐type sesquiterpenoids were revised. A plausible biogenetic relationship between these sesquiterpenoids wasproposed and discussed, and a chemo‐ecological relationship of the title animal and its possible sponge preys has been analyzed. In bioassays, sanyagunin B showed moderate antibacterial activity, whereas 4α‐formamidogorgon‐11‐ene exhibited potent cytotoxicity with IC50 values ranging from 0.87 to 1.95 μM. [ABSTRACT FROM AUTHOR]

Review: 238 refs. [ABSTRACT FROM AUTHOR]

A bio-inspired strategy is used to complete the formal synthesis of the antitubercular hirsutellone B (I) and congeners A (II) and C (III), through construction of its decahydrofluorene core from a linear polyene strand activated at both ends by a silyl enol ether and an allyl acetate (not shown). [ABSTRACT FROM AUTHOR]

Review: 115 refs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A detailed chemical investigation of the South China Sea nudibranch Hexabranchus sanguineus, as well as its possible sponge‐prey Acanthella cavernosa, led to the isolation of fifteen new nitrogenous sesquiterpenoids, namely ximaocavernosins A−O, including seven cadinanes (1—7), seven spiroaxanes (12—18) and one aromadendrane (19), together with thirteen known related compounds (8—11 and 20—28). Compounds (±)‐1—9 (except for 4 and 6) were further separated by chiral‐phase HPLC to their corresponding unequal enantiomers, respectively. Their structures and absolute configurations were determined by a combination of extensive spectroscopic data analysis, quantum mechanical nuclear magnetic resonance (QM‐NMR) methods, Mosher's method, X‐ray diffraction analysis and/or time‐dependent density functional theory/electronic circular dichroism (TDDFT‐ECD) calculation. The commonly existed nitrogenous sesquiterpenoids in these two animals are suggested to be chemical markers for their prey‐predator relationship. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Two new bis‐quinolizidine alkaloids, neopetrosiasins A (1) and B (2), possessing cis‐ and trans‐quinolizidine nuclei, one known related analogue petrosin (3) and three known xestospongins (4—6), were isolated from the South China Sea sponge Neopetrosia chaliniformis. The structures of new compounds were unambiguously determined by extensive spectroscopic and single‐crystal X‐ray analyses. In bioassay, compounds 4—6 exhibited moderate cytotoxicity against several human cancer cells. [ABSTRACT FROM AUTHOR]

Abstract: Nine (1–9) and seven (1–6, 10) compounds were isolated from the fruits of Sonneratia caseolaris and Sonneratia ovata, respectively. Their structures were identified by comparing their MS and NMR data as well as the physical properties with the literature. All the isolated compounds were screened against a rat glioma C-6 cell line using the MTT assay method; only compounds (-)-(R)-nyasol (1), (-)-(R)-4′-O-methylnyasol (2) and maslinic acid (6) were found to show moderate cytotoxic activity. Our findings from these two kinds of fruits can be used as a foundation for further chemotaxonomic studies on Sonneratia species. The nor-lignans (1, 2) and 6H-benzo[b,d]pyran-6-one derivatives (3, 4) were isolated from this genus for the first time, indicating that these two classes of compounds may tentatively be considered as taxonomic markers for Sonneratia genus. [Copyright &y& Elsevier]

Main observation and conclusion: Four new cembranoids, 6‐oxo‐cembrene‐A (1), lobocrassins G—H (2—3), and 14‐epi‐lobophytolide B (4), along with eight known related compounds (5—12), were isolated from the South China Sea soft coral Lobophytum crassum. Their structures were established by extensive spectroscopic analysis and by comparison of the spectral data with those reported in the literatures. The absolute stereochemistry of 14‐epi‐lobophytolide B (4) was established by time‐dependent density functional theory electronic circular dichroism (TDDFT‐ECD) calculations, whereas that of three known metabolites (6, 11 and 12) was also determined, for the first time, by using modified Mosher's method and/or X‐ray diffraction analyses. In bioassay, the cembranoids 6, 7 and 12 showed significant anti‐tumoral activity against A549, HT‐29, SNU‐398 and Capan‐1 tumor cell lines with IC50 values ranging from 1.5 to 7.4 μmol/L. A preliminary structure‐activity relationship was also discussed. [ABSTRACT FROM AUTHOR]

Placobranchus ocellatus is well known to produce diverse and complex γ‐pyrone polypropionates. In this study, the chemical investigation of P. ocellatus from the South China Sea led to the discovery and identification of ocellatusones A–D, a series of racemic non‐γ‐pyrone polyketides with novel skeletons, characterized by a bicyclo[3.2.1]octane (1, 2), a bicyclo[3.3.1]nonane (3) or a mesitylene‐substituted dimethylfuran‐3(2H)‐one core (4). Extensive spectroscopic analysis, quantum chemical computation, chemical synthesis, and/or X‐ray diffraction analysis were used to determine the structure and absolute configuration of the new compounds, including each enantiomer of racemic compounds 1–4 after chiral HPLC resolution. An array of new and diversity‐generating rearrangements is proposed to explain the biosynthesis of these unusual compounds based on careful structural analysis and comparison with six known co‐occurring γ‐pyrones (5–10). Furthermore, the successful biomimetic semisynthesis of ocellatusone A (1) confirmed the proposed rearrangement through an unprecedented acid induced cascade reaction. [ABSTRACT FROM AUTHOR]

Placobranchus ocellatus is well known to produce diverse and complex γ‐pyrone polypropionates. In this study, the chemical investigation of P. ocellatus from the South China Sea led to the discovery and identification of ocellatusones A–D, a series of racemic non‐γ‐pyrone polyketides with novel skeletons, characterized by a bicyclo[3.2.1]octane (1, 2), a bicyclo[3.3.1]nonane (3) or a mesitylene‐substituted dimethylfuran‐3(2H)‐one core (4). Extensive spectroscopic analysis, quantum chemical computation, chemical synthesis, and/or X‐ray diffraction analysis were used to determine the structure and absolute configuration of the new compounds, including each enantiomer of racemic compounds 1–4 after chiral HPLC resolution. An array of new and diversity‐generating rearrangements is proposed to explain the biosynthesis of these unusual compounds based on careful structural analysis and comparison with six known co‐occurring γ‐pyrones (5–10). Furthermore, the successful biomimetic semisynthesis of ocellatusone A (1) confirmed the proposed rearrangement through an unprecedented acid induced cascade reaction. [ABSTRACT FROM AUTHOR]

Benzoxepane derivatives were designed and synthesized, and one hit compound emerged as being effective in vitro with low toxicity. In vivo, this hit compound ameliorated both sickness behavior through anti‐inflammation in LPS‐induced neuroinflammatory mice model and cerebral ischemic injury through anti‐neuroinflammation in rats subjected to transient middle cerebral artery occlusion. Target fishing for the hit compound using photoaffinity probes led to identification of PKM2 as the target protein responsible for anti‐inflammatory effect of the hit compound. Furthermore, the hit exhibited an anti‐neuroinflammatory effect in vitro and in vivo by inhibiting PKM2‐mediated glycolysis and NLRP3 activation, indicating PKM2 as a novel target for neuroinflammation and its related brain disorders. This hit compound has a better safety profile compared to shikonin, a reported PKM2 inhibitor, identifying it as a lead compound in targeting PKM2 for the treatment of inflammation‐related diseases. [ABSTRACT FROM AUTHOR]

Benzoxepane derivatives were designed and synthesized, and one hit compound emerged as being effective in vitro with low toxicity. In vivo, this hit compound ameliorated both sickness behavior through anti‐inflammation in LPS‐induced neuroinflammatory mice model and cerebral ischemic injury through anti‐neuroinflammation in rats subjected to transient middle cerebral artery occlusion. Target fishing for the hit compound using photoaffinity probes led to identification of PKM2 as the target protein responsible for anti‐inflammatory effect of the hit compound. Furthermore, the hit exhibited an anti‐neuroinflammatory effect in vitro and in vivo by inhibiting PKM2‐mediated glycolysis and NLRP3 activation, indicating PKM2 as a novel target for neuroinflammation and its related brain disorders. This hit compound has a better safety profile compared to shikonin, a reported PKM2 inhibitor, identifying it as a lead compound in targeting PKM2 for the treatment of inflammation‐related diseases. [ABSTRACT FROM AUTHOR]

The first and in-depth chemical investigation of the South China Sea soft coral Sinularia scabra has resulted to the isolation of a library of diverse cembrane type diterpenoids, including six new compounds, namely xiguscabrates A and B (1 and 2), xiguscabral A (3), xiguscabrols A and B (4 and 5), and 8- epi -xiguscabrol B (6), and twenty-seven known analogs (7 – 33). Their structures were elucidated by extensive spectroscopic analysis and by the comparison with literature data. In bioassay, several isolates exhibited inhibitory effects on the ConA-induced T lymphocytes and/or LPS-induced B lymphocytes proliferation. Among them, compound 24 showed considerable specific inhibition on B cell proliferation, with IC 50 value of 4.4 μ M and selectivity index (SI) of 10.9. The structure-activity relationship (SAR) of the tested metabolites was analyzed, and the further mechanism study of the specific B-cell targeted immunosuppressive compound 24 on purified CD19+ B cells was also performed to uncover the effects on the function and maturity of B cells, including cytokines production, abnormal activation, antigen presenting capacity and plasma cells formation. [ABSTRACT FROM AUTHOR]

Five undescribed dolabellane-type diterpenoids (1 – 5), together with three related known ones (6 – 8), were isolated from the soft coral Clavularia viridis. Their structures and stereochemistry were elucidated by extensive spectroscopic analysis and NMR calculation with DP4+ probability analysis. The absolute configurations of 1 and 5 were unambiguously determined by X-ray crystallographic analysis. A plausible biosynthetic connection between undescribed compounds 1 – 5 was proposed. Five undescribed dolabellane-type diterpenoids (1 – 5), together with three related known ones (6 – 8), were isolated and structurally characterized from the soft coral Clavularia viridis. [Display omitted] • Five undescribed dolabellane-type diterpenoids were isolated from the soft coral Clavularia viridis. • The X-ray crystallographic and NMR calculation analysis were applied to establish the stereochemistry. • All compounds were evaluated for their cytotoxicity and PTP1B inhibitory activity. [ABSTRACT FROM AUTHOR]

Three new scalarane-type sesterterpenes, namely Hyrtiosins H−J (1−3), along with thirteen known related compounds (4−16), were isolated from the South China Sea sponge Hyrtios erecta. Their structures were elucidated by extensive spectroscopic analysis and by the comparison of their spectroscopic data with those reported in the literature. The stereochemistry of heteronemin (9) was determined for the first time by X-ray crystallography study using Cu K α radiation. In bioassay, compound 5 and 10 displayed considerable inhibitory activity against human protein tyrosine phosphatase 1B (PTP1B) enzyme with IC 50 values of 19.68 μM, and 8.81 μM, respectively. [Display omitted] • Sixteen scalarane sesterterpenes, including three new ones, were isolated from the South China Sea Sponge Hyrtios erecta. • The configurations of compounds were determined by extensive spectroscopic analysis and comparison withthe reported data. • Compounds 5 and 10 displayed significant inhibitory activity against human protein tyrosine phosphatase 1B (PTP1B) enzyme. [ABSTRACT FROM AUTHOR]

Since the adoption of some ambiguous and quantitative characters in Flora Republicae Popularis Sinicae 3(1), species identifications of the series Gravesiana have been in disarray, requiring clarification. Two hundred and fifty-nine individuals from 47 different populations were collected for the estimation of morphological characters and phylogenetic analyses. Spores of 26 populations were observed through scanning electron microscope. Our results were different from those of previous research: (1) six identifiable species, rather than five species observed previously, were confirmed in the series Gravesiana, they are A. gravesii, A. juxtapositum, A. mariesii, A. dentatum, A. longzhouensis and A. obovatum, of which the latter three are newly recognized species. (2) Thirteen characters were measured and estimated through the program Mesquite v. 2.71. The character whether the pinna stalks were 1/3-1/2 times longer than the pinna was used to distinguish A. gravesii and A. lianxianense previously and was found to be unreliable here, whereas such characters as the height of the plant (H), pinna aligned forms (FP), number of pinna (NP), pinna margin (M), number of veins flabellate at base (NV), sori number and shape per pinna (NSS), pinna texture (T), and powder-covered or not on the abaxial surface of the pinna (P) are estimated to be stable and reliable characters useful for identification. Descriptions of new species and their retrieve keys are also listed. (3) Surface ornamentations and spore sizes are helpful for us to distinguish species in series Gravesiana. [ABSTRACT FROM AUTHOR]

[Display omitted] A series of 1- O -acyl- and 1-oxo-kamebanin analogues were prepared from kamebanin, isolated from Rabdosia excisa and their cytotoxicity was assayed on HL60 promyelocytic leukemia cells and HCT116 human colon cancer cells. The structure–activity relationship study showed that the presence of 1- O -acyl groups of a C 3 –C 5 carbon chain increased the cytotoxic activity. [ABSTRACT FROM AUTHOR]

A series of tetrandrine derivatives were designed and synthesized using Suzuki coupling reaction. Eleven targeted compounds with over 50% inhibition against HL60 and A549 human cancer cell lines at 10 μM were further evaluated for the in vitro antitumor activities by MTT or SRB assay. The biological results revealed that some compounds exhibited potent antitumor activities. Thiophene derivative 6 and acetylphenyl derivative 5 were the most active ones against HL60 and A549 cell lines, with IC50 values less than 5 μM, which thus could be considered as useful candidate for further development of new antitumor agents. [ABSTRACT FROM AUTHOR]

Nine new bicyclic cembranoids, sarcophytrols M-U(1-9), were isolated from the South China Sea soft coral Sarcophyton trocheliophorum as minor components, along with one known related cembranoid 10. Their structures were elucidated by detailed spectroscopic analysis and chemical conversion. The chemical structures of these metabolites are characterized by the different patterns of the additional cyclization within the 14-member skeleton, which leading to the formation of furan, pyran, oxepane, and peroxyl rings, respectively. Among them, sarcophytrols R and S(6 and 7) share a rare decaryiol skeleton with an unusual C12/C15 cyclization. In addition, the absolute configurations of sarcophytrols M and T(1 and 8) were determined by the modified Mosher's method. The research of these new secondary metabolites provided a further understanding of the diversity of cyclized cembranoids from the title species. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of phidianidine derivatives were synthesized to study anti-inflammatory activity. • Compounds 9a and 22c exhibited excellent anti-inflammatory activity and low toxicity on IL-17A production in PMA and ionomycin-stimulated EL4 cells. • Compound 9a could decrease the STAT3 phosphorylation at Y705 to inhibit IL-17A production in EL-4 cells. • Molecular docking analysis explained our SAR study. Phidianidines A and B are novel marine indole alkaloids with various biological activities. Based on their potential anti-inflammatory properties, a series of phidianidine derivatives were designed, synthesized, and tested for their effects on IL-17A production in PMA/ionomycin-stimulated T -cell-lymphoma EL-4 cells. Compounds 9a and 22c exhibited excellent anti-inflammatory activity and low toxicity, with IC 50 values of 7.7 μM and 5.3 μM for IL-17A production in PMA/ionomycin-stimulated EL-4 cells, respectively. Further mechanistic study showed that 9a could decrease the STAT3 phosphorylation at Y705 to inhibit IL-17A production in EL-4 cells, indicating its ability of preventing the differentiation of Th17 cells and their possible function. This research may give an insight for the discovery of marine indole alkaloid derived anti-inflammatory drug leads for the treatment of T cell-mediated diseases. [ABSTRACT FROM AUTHOR]

A series of chiral oxazino-indoles have been synthesized via a key intermolecular oxa-Pictet–Spengler reaction. These compounds exhibited significant and selective neuroprotective effects against Aβ 25–35 -induced neuronal damage. This is the first report of evaluating the influence of chiral diversity of oxazino-indoles on their neuroprotective activities, with the structure–activity relationship been analyzed. The highly active compounds 3f , 3g , 4g , 4h , and 6b all performed over 90% cell protection, providing a new direction for the development of neuroprotective agents against Alzheimer’s disease. [ABSTRACT FROM AUTHOR]

Two new highly oxidized formamidobisabolene sesquiterpenes ( 1 and 2), together with seven known related analogues ( 3 - 9), were isolated from a Hainan sponge Axinyssa variabilis. Their structures were determined by extensive 1D- and 2D- NMR and MS spectra analyses, and by comparison of their spectroscopic data with those of the related model compounds. The plausible biosynthetic relationship between compounds 1 - 9 has also been described. [ABSTRACT FROM AUTHOR]

A series of phidianidine B derivatives were synthesized by introducing various heterocyclic rings. Their inhibitory effects on PTP1B and other PTPs (TCPTP, SHP1, SHP2 and LAR) were evaluated. A majority of them displayed significant inhibitory potency and specific selectivity over PTP1B. The SAR and molecular docking analysis were also described. [ABSTRACT FROM AUTHOR]

Two new laurane-type sesquiterpenoids, debromo-3α-hydroperoxy-3-epiaplysin (1) and debromo-3β-hydroperoxyaplysin (2), together with seven known related compounds (3–9), were isolated from the Chinese red algaLaurencia okamurai. Their structures were elucidated by detailed analysis of spectroscopic data and by comparison with the literature. In bioassay, compounds2,4,8,and9exhibited significant PTP1B inhibitory activity with IC50values ranging from 4.9 to 14.9 μg/ml. [ABSTRACT FROM PUBLISHER]

[Display omitted] • First synthesis of five Polybrominated Diphenyl Ethers natural products and 30 new derivatives. • Discovery of two compounds 3 and 17 h selectively act on KCNQ1 and KCNQ2 ion channels. • Provide a class of compounds targeting KCNQ1 and KCNQ2 potassium channels. Natural polybrominated diphenyl ethers, often isolated from marine sponges, have been reported to possess various biological activities, such as antibacterial, antioxidant and antidiabetic effects. Via a high throughput screening of our marine natural product library, the polybrominated diphenyl ether 3 was found to display a KCNQ potassium channel activation effect. To obtain more compound 3 related natural products and their derivatives for further bioactivity study, a diversity-oriented synthesis was conducted, leading to the successful synthesis of five polybrominated diphenyl ether natural products (1 – 4 , 6) and 30 new derivatives. Compound 3 was found to preferentially potentiate KCNQ1 potassium channel, whereas 17h relatively activated KCNQ2 potassium channel. The structure–activity relationship was analyzed assisted by molecular docking and 17h was further conducted for its agonistic mechanism study on KCNQ2 channel. This research work may give an insight for the discovery of marine polybrominated diphenyl ether derived new drug leads. [ABSTRACT FROM AUTHOR]

A method of ionic liquid salt aqueous two-phase extraction coupled with high-performance liquid chromatography has been developed for the analysis of seven rare ginsenosides including Rg6, F4, 20(S)-Rg3, 20(R)-Rg3, Rk3, Rk1, and Rg5 in Xue-Sai-Tong injection. The injection was mixed with ionic liquid 1-butyl-3-methylimidazolium bromide aqueous solution, and a mixture was obtained. With the addition of sodium dodecyl sulfate and dipotassium phosphate into the mixture, the aqueous two-phase mixture was formed after ultrasonic treatment and centrifuged. Rare ginsenosides were extracted into the upper phase. To obtain a high extraction factors, various influences were considered systematically, such as the volume of ionic liquid, the category and amount of salts, the amount of sodium dodecyl sulfate, the pH value of system, and the time of ultrasonic treatment. Under the optimal condition, rare ginsenosides in Xue-Sai-Tong injection were enriched and detected, the recoveries of seven rare ginsenosides ranged from 90.05 to 112.55%, while relative standard deviations were lower than 2.50%. The developed method was reliable, rapid and sensitive for the determination of seven rare ginsenosides in the injections. [ABSTRACT FROM AUTHOR]

[Display omitted] • This is the first chemical study of Sinularia pedunculata from the South China Sea. • Three new diterpenoids (1 – 3) were isolated from Sinularia pedunculata. • The quantum mechanical (QM)-NMR methods and spectroscopic analyses were applied to determine relative configurations. • A plausible biosynthetic pathway of compounds 1 – 3 was proposed. Three new diterpenoids (1 – 3), along with four known related compounds (4 – 7), were isolated from the South China Sea soft coral Sinularia pedunculata. Their structures were established by extensive spectroscopic analysis and by comparison of the spectral data with those reported in the literature. The relative configuration of the new compounds was established by spectroscopic analyses and quantum mechanical (QM)-NMR methods. [ABSTRACT FROM AUTHOR]

isolation and structure elucidation [ABSTRACT FROM AUTHOR]

Abstract: Transformation of plant-origin 7,14-dihydroxy-ent-kaurenes to ent-abietanes having a cis-fused α-methylene γ-lactones was accomplished efficiently under the Mitsunobu reaction conditions. The yields of the desired products were apparently influenced by the steric hindrance at C-1. The cytotoxic activity on P388 murine leukemia cells of the ent-abietanes having cis-fused α-methylene γ-lactones produced were assayed. [Copyright &y& Elsevier]

Abstract: A series of rabdokunmin C analogues were prepared and their inhibitory effect on NF-κB activation was assayed. One of them, 18-acetyl-12-deoxy-11,12-dehydrorabdokunmin C (16) was found to be a promising candidate for an anti-inflammatory agent. [Copyright &y& Elsevier]

Abstract: 1-O-Monoacyl, 12-O-monoacyl, 1-,12-O-diacyl, and 11,12-dehydrated excisanin A 7,14-acetonides were synthesized from excisanin A isolated from Rabdosia excisa. The structure and cytotoxic activity relationships (SAR) of the natural parent ent-kaurene diterpenes and these semisynthetic analogues were studied by using P388 murine leukemia cells. [Copyright &y& Elsevier]

Facile transformation of 7,14-dihydroxy-ent-kaurenes such as excisanin A (8), kamebanin (9), and kamebakaurin (10), which are abundant in plants of the genus Rabdosia species (Labiatae), to ent-abietanes was accomplished under the Mitsunobu reaction conditions. The δ, ϵ-unsaturated cis-fused α-methylene γ-lactones (17, 18, and 25) thus prepared showed a moderate cytotoxic activity on P388 murine leukemia cells. [Copyright &y& Elsevier]

Chemical study of a Hainan sponge Halichondria sp. resulted in the isolation of eight new formamidobisabolene-based sesquiterpenes halichines A–E (1 – 3 , 7 , 8), ent-axinyssine G [(−)- 4 ], ent-axinyssine J [(−)- 5 ], and ent-axinyssine K [(−)- 6 ], along with five related known ones [(+)- 4 , (+)- 5 , (+)- 6 , 10 , 11 ]. Their structures were determined on the basis of extensive spectroscopic analyses, and the absolute configuration of halichine A (1) was determined by Snatzke's method. In bioassay, compounds 3 and 7 displayed considerable anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated BV-2 microglia cells. [Display omitted] • Eight new nitrogenous sesquiterpenes were isolated from the Hainan sponge Halichondria sp. • Snatzke's method was used for the assignment of absolute configurations of 1. • 3 and 7 displayed considerable anti-inflammatory activity in LPS-stimulated BV-2 cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • Seven novel casbane diterpenoids were isolated from Sinularia erecta. • Sinuereperoxides B and C are two rare casbane diterpenoids with an uncommon 8,10-peroxide bridge. • The quantum chemical calculations and X-ray diffraction analysis were applied to determine absolute configurations. • Anti-inflammatory activity by the inhibition of TNF-α release was evaluated. A further systematically chemical investigation of the South China Sea soft coral Sinularia erecta led to the discovery of two rare casbane diterpenoids with an uncommon 8,10-peroxide bridge, sinuereperoxides B (1) and C (2), five new casbanes with other oxygenated patterns (3 – 7), and seven known casbanes (8 – 14). The structures and absolute configurations of 1 – 7 were established by extensive spectroscopic data analyses, X-ray diffraction analysis, and/or quantum chemical calculations. In bioassay, compounds 2 , 7 , 11 and 12 exhibited considerable anti-inflammatory activity by the inhibition of TNF-α release, with IC 50 values of 33.8 μM, 5 μM, 9.9 μM and 8 μM. [ABSTRACT FROM AUTHOR]

[Display omitted] • New cembranoid derivatives were obtained by diversity-oriented synthetic strategy. • 11 displayed the most promising anti-inflammation activity. • Our SAR study were explained by the molecular docking analysis. • 11 could suppress the mRNA expression level of inflammatory mediators. Eleven novel cembranoid derivatives were designed, synthesized, and evaluated for their inflammation related activities on the basis of our isolated and previously reported anti-inflammatory marine cembranoids. In bioassay, compound 11 displayed the most promising inhibitory effects with IC 50 value of 1.1 μM for the TNF-α inhibitory activity. The further mechanism study of 11 on the inflammatory signaling transduction of RAW264.7 cells was also performed. This research may give an insight for the discovery of marine cembranoid derived anti-inflammatory drug leads. [ABSTRACT FROM AUTHOR]

• New cembranoids were isolated and identified from the Hainan soft coral Sarcophyton crassocaule. • A pair of enantiomers were purified by chiral HPLC. • The absolute configurations were determined by TDDFT-ECD calculation, modified Mosher's method, and/or Snatzke's method. The determination of the stereochemistry of cembrane type diterpenoids is always a challenging task due to the flexibility of the 14-membered macrocycle. In this paper, three new cembranoids, ximaocembrols A–C (1 – 3), were isolated from the Hainan soft coral Sarcophyton crassocaule , and ximaocembrol C was further separated by chiral HPLC to its corresponding enantiomers (±)- 3 , respectively. The absolute configurations of these new compounds were successfully elucidated by using a series of reliable approaches, including extensive spectroscopic analysis, TDDFT-ECD calculation, modified Mosher's method, and Snatzke's method. [ABSTRACT FROM AUTHOR]

isolation and structure determination [ABSTRACT FROM AUTHOR]

isolation and structure determination [ABSTRACT FROM AUTHOR]