Two new spongian diterpene analogues isolated from the marine sponge Acanthodendrilla sp

Abstract

Two new marine natural compounds, 3β-acetoxy-15-hydroxyspongia-12-en (1) and 3-methylspongia-3,12-dien-16-one (2), were isolated from the marine sponge Acanthodendrilla sp., collected in Pulau-Pulau. Compounds 1 and 2 represent new chemical entities of the known spongian diterpene family. Compound 1 is a new 3-acetoxyspongia and compound 2 presents an unreported rearranged 3-methylspongia-3-en. Their structures, including relative configurations, were fully elucidated based on 1D and 2D NMR analyses, as well as HRESTOFMS experiments. No significant bioactivities were found for these compounds. This work reports two new chemical structures, compounds 1 and 2, together with the first isolation of spongian diterpenes from Acanthodendrilla genus.     

Two new dammarane-type triterpene sapogenins from Chinese red ginseng

Two new dammarane-type triterpene sapogenins were isolated from the Chinese red ginseng. The new sapogenins were named as 24,26-dihydroxy-panaxdiol (1) and 24-hydroxy-panaxdiol (2). Their structures were elucidated by the combined analysis of NMR and mass spectrometry as 20(S),25(R)-epoxydammarane-3β,12β,24β,26-tetraol (1) and 20(S),25-epoxydammarane-3β,12β,24α-triol (2). The complete signal assignments of the two compounds were carried out by 2D NMR spectral and NOE differential spectroscopy analysis.     

New ent-kaurane diterpenoid dimer from Pulicaria inuloides

A new naturally occurring ent-kaurane diterpenoid dimer, 15β, 15′β-oxybis (ent-kaur-16-en-19-oic acid) (1) along with six known compounds, 15β-hydroxy-ent-kaur-16-en-19-oic acid (2), 15β-hydroxy-ent-kaur-16-en-19-oate-β-d-glucopyranoside (3), 6-hydroxykaempferol-3, 7-dimethyl ether (4), quercetagetin 3, 7, 3′-trimethyl ether (5), β-sitosterol (6) and β-sitosterol glucoside (daucosterol) (7) were isolated from the aerial parts of Pulicaria inuloides DC. Compounds 2–5 were isolated for the first time from genus Pulicaria. The structures of compounds 1–7 were established on the basis of extensive 1D and 2D NMR spectroscopic techniques in combination with ESI-MS. The antimicrobial activity of the isolated compounds was evaluated against Staphylococcus aureus, Escherichia coli and Candida albicans. Sulphorhodamine B cytotoxic assay against HepG2 (liver cancer) cell line and ABTS antioxidant assay were carried out.     

Two new eremophilenolides from the roots of Ligulariopsis shichuana and their anti-phytopathogenic fungal and antifeedant activities

Two new eremophilenolides, ligushicins A (1) and B (2), and two known compounds including β-sitosterol and ursolic acid were isolated from Ligulariopsis shichuana. The structures of new compounds were established on the basis of 1D and 2D NMR data and HRESIMS data interpretation. The absolute configuration of new compounds was assigned by ECD spectroscopy, and that of ligushicins A (1) was confirmed by X-ray diffraction analysis. The antifungal and antifeedant activities of new compounds were evaluated against four plant pathogenic fungi and third-instar larvae of Plutella xylostella, respectively. Ligushicins A (1) and B (2) exhibited potent antifungal activity against Botrytis cinerea and Fusarium oxysporum with minimum inhibitory concentration (MIC) values ranging from 50 to 100 mg/L, while they also exhibited weak antifeedant activities.     

Two new polyhydroxylated triterpenoids from Salvia urmiensis and their cytotoxic activity

Two new polyhydroxylated triterpenoids were isolated from the acetone extract of the aerial parts of Salvia urmiensis Bunge. Their structures were elucidated by 1D and 2D NMR and HR-ESI-MS analyses as olean-12-ene-1β,3β,11α,22α-tetraol (1) and urs-12-ene-1β,3β,11β,22α-tetraol (2). The effect of these compounds on cell viability of MCF-7 cells was investigated by the MTT assay. Compounds 1 and 2 showed weak cytotoxicity with IC₅₀ values of 110.23 ± 0.12 and 88.35 ± 0.09 μM, respectively.     

Saponins from the roots of Chenopodium bonus-henricus L.

Two new glycosides of phytolaccagenin and 2β-hydroxyoleanoic acid, namely bonushenricoside A (3) and bonushenricoside B (5) together with four known saponins, respectively compounds 3-O-L-α-arabinopyranosyl-bayogenin-28-O-β-glucopyranosyl ester (1), 3-O-β-glucuronopyranosyl-2β-hydroxygypsogenin-28-O-β-glucopyranosyl ester (2), 3-O-β-glucuronopyranosyl-bayogenin-28-O-β-glucopyranosyl ester (4) and 3-O-β-glucuronopyranosyl-medicagenic acid-28-β-xylopyranosyl(1→4)-α-rhamnopyranosyl(1→2)-α-arabinopyranosyl ester (6) were isolated from the roots of Chenopodium bonus-henricus L. The structures of the compounds were determined by means of spectroscopic methods (1D and 2D NMR, IR and HRMS). The MeOH extract and compounds were tested for cytotoxic activity on five leukemic cell lines (HL-60, SKW-3, Jurkat E6-1, BV-173 and K-562). In addition, the ability of metanolic extract and saponins to modulate the interleukin-2 production in PHA/PMA stimulated Jurkat E6-1 cells was investigated as well.     

Two new sesquineolignans from the seeds of Crataegus pinnatifida and their β-amyloid aggregation inhibitory activitiy

Two new sesquineolignans, hawthornsesquinins K and L (1 and 2), were isolated from the seeds of Crataegus pinnatifida. Their structures were determined by spectroscopic analyses, including 1D, 2D NMR and HRESIMS data. All isolated compounds were tested for their β-amyloid aggregation inhibitory activity and neuroprotective effects against H₂O₂-induced damage in SH-SY5Y cells. The results indicated that compound 1 showed prominent inhibition of Aβ_1–42 aggregation and significant neuroprotective effect on H₂O₂-induced cellular damage in SH-SY5Y cells.     

Two new 14, 15-secopregnane-type steroidal glycosides from the roots of Cynanchum limprichtii

Two new steroidal glycosides 1 and 2, along with three known ones (3–5), were isolated from the 95% ethanol extract of the roots of Cynanchum limprichtii Schltr. The structure of the new compounds was elucidated as 3-O-α-L-diginopyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-thevetopyranosyl-14, 16:15, 20:18, 20-triepoxy-14, 15-secopregn-4, 6, 8 (14)-triene (1) and 3-O-α-L-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl- (1→4)-β-D-3-demethyl-2-deoxythevetopyranosyl-14, 16: 15, 20: 8, 20-triepoxy-14, 15-secopregn-5, 8 (14)-diene (2) on the basis of spectroscopic analysis together with acidic hydrolysis. All compounds showed cytotoxic activity against the human cancer cell line HL60, with IC₅₀ values of 55.36, 65.41, 17.88, 17.68 and 33.5 μM, respectively. While, only compound 3 showed cytotoxicity against the Caco-2 cell line, with an IC₅₀ value of 67.47 μM.     

New cucurbitane-type triterpenoid glucosides from the tubers of Hemsleya amabilis with anti-tumor activity

Abstract

Two new cucurbitane-type triterpenoid glucosides, 3β,11α-dihydroxycucurbita-5,24(E)-diene-3,26-glucosides (1) and 3β,11α-dihydroxycucurbita-5,24(Z)-diene-3,27-glucosides were isolated from the tubers of Hemsleya amabilis. Their structures were elucidated by various spectroscopic techniques including IR, HRESIMS, 1D and 2D NMR. The two compounds were evaluated for their anti-tumor activity against HeLa and HepG-2 cell lines, and both displayed moderate anti-tumor activity towards HeLa cell lines with IC₅₀ values of 9.8 and 15.7?μM, respectively.     

Two new ionone glycosides from the roots of Rehmannia glutinosa Libosch.

Two new ionone glycosides, named frehmaglutoside G (1) and frehmaglutoside H (2), together with six known compounds, rehmapicroside (3), sec-hydroxyaeginetic acid (4), dihydroxy-β-ionone (5), trihydroxy-β-ionone (6), rehmaionoside A (7) and rehmaionoside C (8), were isolated from the 95% EtOH extract of the dried roots of Rehmannia glutinosa Libosch. Their structures were determined on the basis of extensive spectroscopic analyses, including HR-ESI-MS, UV, IR, 1D and 2D NMR (¹H–¹H COSY, HSQC, HMBC and NOESY) methods. The absolute configurations were confirmed via the circular dichroism spectra.     

Terpenoids from the barks of Magnolia maudiae (Dunn) Figlar

A new germacrenolide (1) and fourteen known terpenoids (2–15) were isolated from the barks of Magnolia maudiae (Dunn) Figlar (Magnoliaceae). The structure of (7αH,11βH)-2α,8α-dihydroxy-4α,5β-epoxy-germacr-1(10)-en-6α,12-olide (1) was elucidated by physical and spectroscopic data analysis, including 1D, 2D NMR and HR-ESI-MS. Lyratol F (9) was isolated from Magnolia for the first time. The structures of known compounds were established by comparing their spectroscopic data with those in literatures.     

Chemical constituents from Gueldenstaedtia verna and their anti-inflammatory activity

A new triterpenoid glycoside (1) and 15 known compounds (2–16) were isolated from the whole plants of Gueldenstaedtia verna. The new compound (1) was identified as complogenin 22-O-β-d-glucopyranoside by extensive spectroscopic techniques including 1D (¹H and ¹³C) and 2D NMR experiments (HSQC, HMBC and NOESY), HR-DART-MS and chemical methods. Most of the isolates were evaluated for their inhibitory activities on LPS-induced NO production in RAW 264.7 cells. The inhibitory effects of the active compounds, sulphuretin (8) and (22E,24S)-5α,8α-epidioxy-24-methyl-cholesta-6,9(11),22-trien-3β-ol (13), on the production of pro-inflammatory mediators (including IL-6, IL1β and PGE₂) were further estimated in vitro by ELISA in RAW 264.7 macrophages.     

A new flavanone glycoside isolated from Tournefortia sibirica

A new flavanone glycoside, (2S)-dihydrooroxylin A 7-O-[β-D-apiosyl(1→2)]-β-D-glucoside (1), and four known compounds (2–5) were isolated from Tournefortia sibirica L. The chemical structures of these compounds were determined by 1?D and 2?D NMR and HR-ESI-MS spectra, and results were compared with data from the literature. These five compounds (1–5) were isolated from the family Boraginaceae for the first time. Anti-inflammatory effects of compounds (1–5) were evaluated in terms of inhibition of production of NO, TNF-α, and IL-6 in LPS-induced RAW 264.7 cells.     

New dammarane and ursane-type triterpenoids from the flower of Ixora coccinea Linn.

Two new esters of dammarane triterpenoids ixorene isovalerate (1), ixorene 3′,8′-dimethyloctanoate (2) and a new ursane-type triterpenoids Ixoroid acid (3) were isolated from the methanolic extract of flowers of Ixora coccinea Linn., along with the three known constituents. The structures of compounds 1 and 3 were elucidated on the basis of extensive 1D,2D NMR studies and mass spectrometry as 17β-dammara-12,20-diene-3β-isovelarate and 3β-hydroxy-18β-urs-12ene-29β-oic acid, respectively, whereas 2 was identified as 17β-dammara-12,20-diene-3β-3′,8′-dimethyloctanoate through ¹H NMR and mass spectral data. Compounds 1, 2, 4 and 5 were evaluated for their in vitro cytotoxic activity, which exhibited weak activity against the 3T3, PC3 and HeLa cell lines with the IC₅₀ value >30 μM. Antioxidant results of 1 – 5 revealed that only compound 5 showed antioxidant activity in DPPH radical scavenging inhibition with the IC₅₀ 1.31 × 10^? 6 ± 0.005 μm mL^? 1. Both activities are the first records of these isolated compounds from the flowers of Ixora coccinea Linn.     

Two new triterpenoids from the fungus Diplodia cupressi

Abstract

One new pentanortriterpenoid, 23,24,25,26,27-pentanorlanost-7,9(11)-dien-3β,22-diol (1), one new triterpenoid, lanost-8-en-3β,22S,23S-triol (2), together with the known triterpenoid, 23,24,25,26,27-pentanorlanost-8-en-3β,22-diol (3), were obtained from culture of the fungus Diplodia cupressi associated with the moss Polytrichum commune. The structures of the new compounds were elucidated by extensive spectroscopic techniques including HR-ESIMS and 1?D and 2?D NMR experiments. The cytotoxicity of these compounds against human cancer cell lines (A549, Hep G2, Hepa 1c1c7, and Hela) was evaluated and compound 2 exhibited weak inhibitory activity with IC₅₀ value of 35.0?±?2.3?μM against the proliferation of the Hepa 1c1c7 cells.     

Rubescins I and J,further limonoid derivatives from the stem bark of Trichilia rubescens (Meliaceae)

Two new tetranorterpenoid derivatives named rubescins I (1) and J (2), were isolated along with six known compounds including rubescin D (3), lichexanthone (4), scopoletin (5), scopoletin O-glycoside (6), β-sitosterol (7) and stigmasterol (8) from the stem bark of Trichilia rubescens (Meliaceae). The structures of the compounds were determined by means of MS, different NMR and by comparison with related data reported in the literature.     

Two new quercetin glycoside derivatives from the fruits of Gardenia jasminoides var. radicans

Two new quercetin glycoside derivatives named quercetin-3-O-[2-O-trans-caffeoyl-α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside] (1) and quercetin-3-O-[2-O-trans-caffeoyl-β-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside] (2) along with three known flavonoids, 5-hydroxy-6,7,3′,4′,5′-pentamethoxyflavone (3), 5,7-dihydroxy-8-methoxyflavone (4) and kaempferol 3-O-β-d-glucopyranoside (5), were isolated from the fruits of Gardenia jasminoides var. radicans. The structures of the new compounds were determined by means of extensive spectroscopic analysis (1D, 2D NMR and HR-ESI-MS), glycoside hydrolysis and sugar HPLC analysis after derivatisation. This is the first report on the isolation of a pair of compounds with α or β-l-rhamnopyranosyl configuration from plant and the first detail assignment of their NMR data.     

Two new diarylheptanoids isolated from the roots of Juglans mandshurica

Two new diarylheptanoids, ( ? )-threo-3′,4″-epoxy-1-(4-hydroxyphenyl)-7-(3-methoxyphenyl)heptan-2,3-diol (1) and (1α,3β,5α,6α)-1,5-epoxy-3,6-dihydroxy-1,7-bis(3-methoxy-4-hydroxy-phenyl)-heptane (2), along with one known diarylheptanoid, rhoiptelol B (3), were isolated from the roots of Juglans mandshurica. The structures of compounds 1 and 2 were identified based on HR-ESI-MS, 1D and 2D NMR including ¹H–¹H COSY, HMQC, HMBC and NOESY spectroscopic methods.     

Two new tetralone glycosides from the green walnut husks of Juglans mandshurica Maxim

Two new tetralone glycosides, 4(S)-5-methoxy juglanoside A (1), 4(S)-5-methoxy juglanoside D (2), together with ten known compounds (3–12) have been isolated from the green walnut husks of Juglans mandshurica Maxim. Their structures were elucidated on the basis of their ESI-MS, 1?D and 2?D NMR spectroscopic data. In addition, all compounds were evaluated for their cytotoxic activities against the cancer BGC-823 (human gastric carcinoma), HCT-15 (human colorectal carcinoma) and K562 (human chronic myeloid leukemia) cell lines. The results showed aglycones of naphthoquinones had stronger cytotoxic activities than glycosides of tetralone.     

Two new ent-atisanes from the root of Euphorbia fischeriana Steud.

Two new ent-atisanes ent-1β,3β,16β,17-tetrahydroxyatisane (1), ent-1β,3α,16β,17-tetrahydroxyatisane (2) together with 11 known diterpenes were isolated from the anti-tumour activity fraction of Euphorbia fischeriana Steud. The compounds were identified by detailed spectroscopic analysis, including extensive 2D-NMR experiments. X-ray analysis was applied to determine the structure of compound 2. All 13 compounds were screened for cytotoxicity in vitro against human tumour MCF-7, HepG-2 and SGC-7901 cell lines. Compounds 1 and 2 showed the inhibitory effects against MCF-7 with IC₅₀ levels of 23.21 and 15.42 μM; simultaneously, compounds 4, 6, 8 and 11 also had definite inhibitory effect against different cell lines.