A new polyoxygenated cyclohexene derivative from Artabotrys hainanensis

A new polyoxygenated cyclohexene derivative, artahainanol A (1), together with three known analogues (2–4), was isolated from the stems and leaves of Artabotrys hainanensis. Among them, 1 is an unusual polyoxygenated cyclohexene containing 14 carbon atoms on the carbon skeleton. All known compounds (2–4) were isolated from the genus Artabotrys for the first time. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1–4 showed significant inhibitory effects against various human cancer cell lines with IC₅₀ values ranging from 2.68 to 18.32 μM.     

A new abietane diterpenoid from the roots of Tripterygium regelii

A new abietane diterpenoid, tripterregeline A (1), together with six known diterpenoids (2–7), were isolated from the roots of Tripterygium regelii. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparison with data reported in the literature. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1–7 showed significant inhibitory effects against various human cancer cell lines with IC₅₀ values ranging from 0.58 to 21.06 μM.     

Bioactive furanocoumarins from the stems and leaves of Clausena hainanensis

A new furanocoumarin, clauhainanin A (1), together with seven known furanocoumarins (2–8), were isolated from the stems and leaves of Clausena hainanensis. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All known compounds (2–8) were isolated from C. hainanensis for the first time. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1–8 exhibited significant inhibitory effects with IC₅₀ values ranging from 1.36 to 18.96 μM.     

New p-terphenyl and benzoquinone metabolites from the bioluminescent mushroom Neonothopanus nambi

Abstract

Two new p-terphenyls, neonambiterphenyls A and B (1–2), a new benzoquinone, neonambiquinone A (3), together with six known sesquiterpenes (4–9), were isolated from the bioluminescent mushroom Neonothopanus nambi PW3. The isolated compounds were identified by mass, IR and spectroscopic analyses (1D and 2D NMR). Compounds 1–3 and 5–7 showed cytotoxicity against cancer cell lines such as KB, NCI-H187 and MCF-7 with IC₅₀ values ranging from 1.45 to 49.31?µg/mL. In addition, compounds 1 and 5 showed cytotoxicity against Vero cells with IC₅₀ values of 38.72 and 32.90?µg/mL, respectively.     

Eudesmane and aromadendrane sesquiterpenoids from the Vietnamese soft coral Sinularia erecta

Using various chromatographic separations, eight sesquiterpenoids (1–8), including one new compound 3β,5α-dihydroxyeudesma-4(15),11-diene (1), were isolated from the MeOH extract of the Vietnamese soft coral Sinularia erecta. The structure elucidation was confirmed by spectroscopic experiments including 1D and 2D NMR and HR-ESI-MS. The cytotoxic activities against three human cancer cell lines (A-549, HeLa and PANC-1) of all isolated compounds were evaluated by MTT-based colorimetric assays. Compound 1 exhibited selective cytotoxicity against the A549 cell line with IC₅₀ of 14.79 ± 0.91 μM.     

A new bis-γ-pyrone polypropionate of onchidiol family from marine pulmonate mollusk Onchidium sp

Abstract

A new bis-γ-pyrone polypropionate, 4,16-di-epi-onchidiol (1), along with three known related compounds (2–4) were isolated from the marine pulmonate mollusk Onchidium sp. The structure of compound 1 was elucidated by extensive spectroscopic analysis and by comparison the NMR data with its stereoisomers 2–4, whereas its absolute configuration was determined by the combination of X-ray diffraction analysis and TDDFT-ECD calculation. In bioassay, the isolated compounds exhibited broad cytotoxicity against several cancer cell lines with IC₅₀ values ranging from 24.6 to 88.5μM.     

Bioactive xanthoquinodins and epipolythiodioxopiperazines from Chaetomium globosum 7s-1, an endophytic fungus isolated from Rhapis cochinchinensis (Lour.) Mart

Abstract

A new xanthoquinodin B9 (1), together with two known xanthoquinodins, xanthoquinodin A1 (2) and xanthoquinodin A3 (3), three epipolythiodioxopiperazines, chetomin (4), chaetocochin C (5) and dethio-tetra(methylthio)chetomin (6), and four other compounds, chrysophanol (7), emodin (8), alatinone (9), and ergosterol (10) were isolated from the endophytic fungus Chaetomium globosum 7s-1, isolated from Rhapis cochinchinensis (Lour.) Mart. All isolated structures were established based on their spectroscopic data analyses. Compounds 1–6 showed antibacterial activity against Gram positive bacteria with MICs ranging from 0.02?pM to 10.81 µM. Compounds 1–6 also exhibited cytotoxicity against KB, MCF-7 and NCI-H187 cancer cell lines (IC₅₀ 0.04–18.40 µM). However, they were cytotoxic towards a normal cell line (Vero cell) with IC₅₀ values ranging from 0.04 to 3.86 µM.     

New 1, 2-naphthoquinone-derived pigments from the mycobiont of lichen Trypethelium eluteriae Sprengel

A new yellow pigment trypethelonamide A (1), and a new dark violet-red pigment 5′-hydroxytrypethelone (2), as well as three known dark violet-red pigments (+)-8-hydroxy-7-methoxytrypethelone (3), (+)-trypethelone (4) and (-)-trypethelone (5) were isolated from the cultured lichenized fungus Trypethelium eluteriae. The structures of 1 and 2 were determined to be 1, 2-naphthoquinone derivatives by extensive spectroscopic analysis. The absolute configurations of 1 and 2 were assigned by quantum electronic circular dichroism (ECD) calculation. All isolated compounds were evaluated for cytotoxicities against A549, HepG2 and RKO cell lines, and antioxidant effects on DPPH. Compounds 1–5 showed moderate and weak cytotoxicities against RKO cell line with IC₅₀ from 22.6 to 113.5 μM.     

Cytotoxic triquinane-type sesquiterpenoids from the endophytic fungus Cerrena sp. A593

Abstract

The culture broth of Cerrena sp. A593, which was isolated from Pogostemon cablin, showed potent cytotoxicity against several human tumor cell lines. The following chemical study resulted in the isolation of two new triquinane-type sesquiterpenoids, named cerrenins D (1) and E (2), along with two known compounds plerocybellone A (3) and chloriolin B (4). Their structures were fully assigned with the aid of extensive spectroscopic analysis (¹H and ¹³C NMR, HSQC, HMBC, ¹H-¹H COSY, HRESIMS, and IR) and data from the literature. Moreover, cytotoxic activity in vitro of compounds 1–4 were evaluated against SF-268, MCF-7, NCI-H460, and HepG-2 tumor cell lines. The new compound 1 exhibited weak growth inhibitory activity against all the four tumor cell lines with IC₅₀ values of 41.01, 14.43, 29.67, 44.32?μM.     

Neoclerodane diterpenoids from Scutellaria barbata with cytotoxic activities

Abstract

Two new neoclerodane diterpenoids, barbatin F (1), barbatin G (2) together with four known compounds, scutebata A (3), scutebata B (4), scutebata C (5) and scutebata P (6) were isolated from the whole plant of Scutellaria barbata D.Don. Their structures were elucidated on the basis of spectroscopic studies. In vitro cytotoxicity of selected compounds against cancer cell lines LoVo, SMMC-7721, HCT-116, and MCF-7 were evaluated, compound 1 and 2 showed weak cytotoxic activities against HCT-116 colon cancer cell lines with IC₅₀ value of 44.3, 32.3?μM, respectively, while compound 3 and 4 exhibited moderate cytotoxic activities against four tested human cancer cell lines with IC₅₀ values of 5.31～28.5?μM.     

A new cytotoxic biflavonoid from the rhizome of Wikstroemia indica

One new chalcone-flavone biflavonoid, 3′-hydroxydaphnodorin A (1), together with 12 known biflavonoids (2–13), was isolated from the rhizome of Wikstroemia indica. Their structures were established on the basis of extensive spectroscopic methods. Eight isolated compounds 1–3, 6, 7, 9, 12 and 13 were evaluated for their cytotoxic activities against cancer-derived cell lines Hep3B, HepG2 and CNE2, and 1 was found to possess moderate cytotoxicity against HepG2 and CNE2 cell lines, with IC₅₀ values of 65.5 ± 11.4 and 53.6 ± 10.1 μM, respectively.     

Calaxanthones A-C,three new xanthones from the roots of Calophyllum calaba and the cytotoxicity

Three new xanthones, named calaxanthones A-C (1–3), along with 17 known xanthones (4–20) were isolated from the roots of Calophyllum calaba. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their cytotoxicity against five cancer cell lines (KB, HeLa S-3, HT-29, MCF-7 and HepG-2). Compound 3 showed potent cytotoxicity against all the five cancer cell lines with IC₅₀ values in the range of 0.82–5.04 μM. Furthermore, compound 6 showed potent cytotoxicity against KB, HeLa S-3 and HepG2 cells with IC₅₀ values of 7.06, 5.27 and 9.64 μM, respectively. Additionally, compound 7 showed potent cytotoxicity against KB cell with an IC₅₀ value of 4.62 μM.     

A new triterpenoid saponin and a diterpene glucoside from the seeds of Orychophragmus violaceus

One new triterpenoid saponin orychoside A (1) and one new diterpene glucoside orychoside B (12), together with eleven known compounds, were isolated from the seeds of Orychophragmus violaceus. The structures of the new compounds were elucidated on the basis of spectroscopic analysis. The known compounds were identified by comparison with data reported in the literature. All compounds were tested for their cytotoxic activities against the HepG2 and A549 cell lines in vitro. The new compound 1 exhibited potent cytotoxicity against the two cell lines with IC₅₀ values of 7.13 and 8.77 μM, respectively. Compounds 2, 5, 8 and 9 were found to possess obvious cytotoxicity.     

Furofuran lignans and alkaloids from Clinacanthus nutans

One new furofuran lignan 2-methoxy-9β-hydroxydiasesamin (1), and four analogues (2–5), together with eight alkaloids (6–13), were isolated from the ethanol extract of the aerial part of Clinacanthus nutans. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. All the compounds were isolated from the genus of Clinacanthus for the first time. In addition, lignans isolated from C. nutans was reported for the first time. Compound 1 exhibited modest activity against three human tumor cell lines Hela, MCF-7, and A549, with IC₅₀ values of 68.55, 60.00, and 59.17 μM, respectively.     

Cytotoxic monoterpenoid indole alkaloids isolated from the barks of Voacanga africana Staph.

A new monoterpenoid indole alkaloid compound (1) and six known monoterpenoid indole alkaloids compounds (2–7) were isolated from the barks of Voacanga africana Staph. The structures were established by spectral analysis as ibogamine-16-carboxylic acid,17,20-didehydro-5,6-dioxo-10-methoxy-methyl ester (1), voacamine (2), vobasine (3), voacangine (4), voacristine (5), 19-epi-voacristine (6) and 19-epi-heyneanine (7). Compound 1 was confirmed by X-ray crystallographic analysis. All of the isolated compounds were evaluated for cytotoxicity against five cell lines (HEPG-2, A375, MDA-MB-231, SH-SY5Y, CT26). Among them, compounds 2 and 6 displayed significant inhibitory activities, compounds 3, 4 and 5 showed moderate inhibitory activities, while compounds 1 and 7 showed no inhibitory activities against the five cell lines.     

Secondary metabolites from Antarctic marine-derived fungus Penicillium crustosum HDN153086

A new polyene compound (1) and a new diketopiperazine (2), as well as three known compounds (3–5), were isolated from the Antarctic marine-derived fungus Penicillium crustosum HDN153086. The structures of 1–5 were deduced based on MS, NMR and TD-DFT calculations of specific ECD spectra. These compounds were evaluated for their cytotoxic activities against K562 cell line and only compound 2 exhibited cytotoxicity against K562 cell, with IC₅₀ value of 12.7 μM.     

A new lumazine peptide penilumamide E from the fungus Aspergillus terreus

A new rare lumazine peptide, penilumamide E (1), together with 13 known compounds (2–14) were isolated from the fungus Aspergillus terreus. Their structures were identified by spectroscopic techniques. The relative configuration of 1 was confirmed by single-crystal X-ray diffraction analysis. Compound 10 exhibited antimalarial activity against Plasmodium falciparum with IC₅₀ values of 2.83 μg/mL. Compounds 4 and 6 showed weak cytotoxicity against cholangiocarcinoma (CCA) cell lines. In addition, 4 and 11 exhibited weak cytotoxicity against human hepatoma cell line.     

Secondary metabolites from the Colletotrichum gloeosporioides A12, an endophytic fungus derived from Aquilaria sinensis

Two new cyclohexene derivatives colletotricones A and B (1 and 2) and a new thiazole derivative colletotricole A (5), along with six known natural metabolites were isolated from the extract of Colletotrichum gloeosporioides A12, an endophytic fungus derived from Aquilaria sinensis. Among them, the colletotricones A and B possess a cyclohexenone skeleton, whereas the colletotricole A is a thiazole derivative. Their structures were fully assigned with the aid of extensive spectroscopic analysis and data from the literature. Moreover, cytotoxic activity in vitro of compounds 1 and 3–9 were evaluated against MCF-7, NCI-H460, HepG-2 and SF-268 tumour cell lines. The new compound 1 exhibited growth inhibitory activity against all the four tumour cell lines with IC₅₀ values ranging from 15.7 to 46.8 μM.     

Furanocoumarins with potential antiproliferative activities from Clausena lenis

A phytochemical investigation on the stems and leaves of Clausena lenis led to the isolation of a new furanocoumarin, clauselenisin A (1), together with five known analogues (2–6). The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All known compounds (2–6) were isolated from C. lenis for the first time. All isolated compounds were evaluated for their their antiproliferative activities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1–6 showed significant antiproliferative effects with IC₅₀ values ranging from 0.36 to 16.48 μM.     

Two new benzophenones and one new natural amide alkaloid isolated from a mangrove-derived Fungus Penicillium citrinum

Two new compounds penibenzophenones A-B (1–2), and the synthetic α,β-unsaturated amide alkaloid (E)-tert-butyl(3-cinnamamidopropyl)carbamate (4), newly identified as a natural product, alone with three known ones (3, 5–6) were isolated from the EtOAc extract of the endophytic fungus Penicillium citrinum HL-5126 isolated from the mangrove Bruguiera sexangula var. rhynchopetala collected in the South China Sea. Compound 1 was a chlorinated benzophenone. The structures of 1–6 were elucidated by extensive NMR spectral interpretation, MS data and X-ray analysis. The new compound 2 displayed cytotoxic activity against human A549 cell lines with an IC₅₀ value of 15.7 μg/mL, and 1 showed antibacterial activity against Staphylococcus aureus with a MIC value of 20 μg/mL.