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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]

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]

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]

• 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]

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]

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]

[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 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]

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]

[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]

[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]

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]

• 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]