New naphthopyrones from marine-derived fungus Aspergillus niger 2HL-M-8 and their in vitro antiproliferative activity

A new cytotoxic dimeric naphthopyrone, aurasperone H (1), together with eight related known polyketides (2–9) was isolated from a marine-derived fungus Aspergillus niger 2HL-M-8. The structure of new compound 1 was elucidated on the basis of its spectroscopic data (1D, 2D NMR and CD). Compound 1 exhibited moderate inhibitory activity against the human lung adenocarcinoma A549 and the human leukaemia HL-60 cell lines. Compound 5 displayed significant in vitro antiproliferative activity against HL-60 cell line with an IC₅₀ value of 0.8 μM.     

Two new cassane diterpene lactams from the fruits of Caesalpinia mimosoides Lam

Two new cassane ditepenoid lactams, caesmimotam A (1) and B (2), along with eight known compounds (3–10) were isolated from the fruits of Caesalpinia mimosoides Lam. Their structures were identified by 1D and 2D NMR spectral data. Compounds 1 and 2 were evaluated for their cytotoxicity on HL-60, SMMC-7721, A-549, MCF-7 and SW-480 human cancer cell lines, but they were inactive.     

New pyrazinoquinazoline alkaloids Isolated from a culture of Stenotrophomonas maltophilia QB-77

Two new pyrazinoquinazoline alkaloids, epi-fiscalin D (1) and epi-fiscalin E (2), as well as three known analogues, norquinadoline A (3), quinadoline A (4), and fiscalin C (5), were isolated from ethyl acetate extract of the fermentation broth of Stentrophomonas maltophilia QB-77. The structures of new compounds were elucidated on the basis of extensive spectroscopic data analysis including UV, HRESIMS, and 1D and 2D NMR experiments. All the isolated compounds were tested for their in vitro cytotoxicity against five human cancer cell lines (SMMC-7721, MCF-7, HL-60, SW480, and A-549) and antibacterial activities against Bacillus subtilis, Escherichia coli, and Staphylococcus aureus.     

A novel daphnane-type diterpene from the flower bud of <Emphasis Type="Italic">Daphne genkwa</Emphasis>

A novel daphnane-type diterpene, genkwanin I (1), and a novel natural product, orthobenzoate 2 (2), were isolated from the flower bud of Daphne genkwa. The structures of the two compounds were elucidated by spectral techniques, viz.1D, 2D NMR spectra and HR-ESI-MS. Genkwanin I showed inhibitory activity against human promyelocytic HL-60 cells at an IC₅₀ level of 11.74 μM.     

A new bioactive diterpenoid from pestalotiopsis adusta,an endophytic fungus from clerodendrum canescens

Bioassay-guided fractionation of the culture extract of Pestalotiopsis adusta, an endophytic fungus isolated from the medicinal plant Clerodendrum canescens, led to the isolation of one new, (10S)-12,16-epoxy-17(15→16)-abeo-3,5,8,12,15-abietapentaen-2,7,11,14-tetraone (1), and four known diterpenoids, teuvincenone F (2), uncinatone (3), coleon U (4), coleon U-12-methyl ether (5). These structures were identified by using spectroscopic methods, including UV, MS, 1D and 2D NMR experiments. This is the first report of these compounds being isolated from a Pestalotiopsis species. The cytotoxic activities of the compounds were evaluated, and compounds 1 and 3 demonstrated cytotoxic activities against the HL-60 tumour cell line (IC₅₀ ＜ 20 μM).     

A new furofuran lignan from Piper terminaliflorum Tseng

The chemical investigation of whole plants Piper terminaliflorum Tseng led to the isolation of one new furofuran lignan, 7-methoxyasarinin (1), along with three known amide alkaloids (2–4) as N-3,5-dimethoxy-4-hydroxycinnamoylpyrrole (2), dihydropipercide (3) and 1-[(2E,4E,9E)-10-(3,4-Methylenedioxyphenyl)-2,4,9-undecatrienoyl]pyrrolidine (4). Their structures were elucidated by extensive spectroscopic analyses, including 1D, 2D NMR and HR-ESI-MS, and by comparison with the literature. Compounds (2–4) were isolated from Piper terminaliflorum Tseng for the first time. All isolated compounds (1–4) were evaluated for their cytotoxic activities against five human cancer cell lines (including A-549, SMMC-7721, HL-60, MCF-7 and SW-480).     

Three new phenanthrenone constituents from Trigonostemonlii

Three new phenanthrenone constituents, trigoxyphins U–W (1, 7 and 9), together with eight known ones, trigoxyphin M (2), 6,9-O-dimethyltrigonostemone (3), trigonstemone (4), thrigonosomone B (5), trigonochinene E (6), actephiiol A (8), epiactephilol A (10) and neoboutomannin (11), were obtained from the methanol extract of the leaves and stems of Trigonostemonlii. The structures of the new metabolites were elucidated by analysing the spectroscopic data (1D NMR, 2D NMR, HR-ESI-MS and IR). Compounds 1–6 were evaluated for their cytotoxic activities on five human tumour cell lines by using the MTT method, and compound 1 exhibited inhibitory activity against HL-60, SMMC-7721, A-549, MCF-7 and SW480 with IC₅₀ values ranging from 3.77 to 14.51 μM.     

Two new phenylpropanoids from the Chinese mangrove Ceriops tagal

Two new phenylpropanoids, tagalphenylpropanoidins A-B (1–2), together with a known analogue, 2,3,6-trimethoxy-5-(1-propenyl)phenol (3), were isolated from the ethanolic extract of the Chinese mangrove Ceriops tagal. The structures of these compounds were determined by extensive spectroscopic analysis, including 1D and 2D NMR and HR-ESI-MS, as well as the comparison with data in the literature. Compound 3 was discovered from this plant for the first time. Cytotoxicities of the three compounds against MCF-7 and HL-60 cancer cell lines were also evaluated.     

New cytotoxic and anti-inflammatory compounds isolated from Morus alba L.

Six Diels–Alder adducts (1–6) and nine prenylated flavanones (7–15) were isolated from the root bark of Morus alba L. Among them, soroceal B (1) and sanggenol Q (7) were new compounds. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D and 2D NMR techniques. Compounds 1–3, 9, 10, 12, 13 and 15 exhibited cytotoxic activity against five human tumour lines and compound 2 inhibited significantly selective cytotoxic activities towards HL-60 and AGS cells with IC₅₀ of 3.4 and 3.6 μM. Compounds 3, 5, 9 and 12 exhibited moderate inhibitory activity against nitric oxide production in LPS-activated RAW264.7.     

One new 19-nor cucurbitane-type triterpenoid from the stems of Momordica charantia

One new 19-nor cucurbitane-type triterpenoid (3β,9β,25-trihydroxy-7β-methoxy-19-nor-cucurbita-5,23(E)-diene) (1), together with other six known cucurbitane-type triterpenoids (2–7), were isolated from the stems of Momordica charantia L. The chemical structure of 1 was elucidated by extensive 1D NMR and 2D NMR (HSQC, HMBC, COSY and ROESY), MS experiments. Using MTT assay, compound 1 exhibited weak cytotoxicity against HL-60, A-549, and SK-BR-3 cell lines with the IC₅₀ values at 27.3, 32.7 and 26.6 μM, respectively.     

MDN-0171, a new medermycin analogue from Streptomyces albolongus CA-186053

A new medermycin derivative, MDN-0171 (1), and two known structurally related compounds, medermycin (2) and antibiotic G15-F (3) were isolated from the acetone extract of culture broths of the marine-derived Streptomyces albolongus strain CA-186053. Their structures were determined using a combination of spectroscopic techniques, including 1D and 2D NMR and electrospray-time of flight mass spectrometry (ESI-TOF MS). Compounds 2 and 3 accounted for the antimicrobial activity (against methicillin-resistant Staphylococcus aureus and Escherichia coli) previously detected in the crude extract of this actinomycete.     

Paenibacillin A,a new 2(1H)-pyrazinone ring-containing natural product from the endophytic bacterium Paenibacillus sp. Xy-2

A new 2(1H)-pyrazinone ring-containing natural product, paenibacillin A (1), together with five known diketopiperazine derivatives 2–6 and two known isoflavones 7–8, was isolated from the culture of an endophytic bacterium Paenibacillus sp. Xy-2. The structure of compound 1 was elucidated by extensive spectral methods, including UV, IR, HR-ESI-MS, 1D and 2D NMR and ECD experiments. Compound 1 exhibited moderate cytotoxicity against HL-60 cell line with IC₅₀ value of 50.48 μM.     

New anti-bacterial halogenated tricyclic sesquiterpenes from Bornean Laurencia majuscula (Harvey) Lucas

Three new halogenated tricyclic sesquiterpenes, omphalaurediol (1), rhodolaurenones B (2) and C (3) were isolated together with nine known haloganated sesquiterpenes such as rhodolaurenone A (4), rhodolaureol (5), isorhodolaureol (6), (?)-laurencenone D (7), elatol (8), (+)-deschloroelatol (9), cartilagineol (10), (+)-laurencenone B (11) and 2-chloro-3-hydroxy-α-chamigren-9-one (12) from a population of Bornean red algae Laurencia majuscula. The structures of three new metabolites were determined based on their spectroscopic data (IR, 1D and 2D NMR, and MS). These compounds showed antibacterial activity against three human pathogenic bacteria (Escherichia coli, Salmonella typhi and Vibrio cholera).     

Cytotoxic triterpene saponins from the mangrove Aegiceras corniculatum

Using various chromatographic separations, sixteen compounds, including one new triterpene saponin named aegicoroside A (1), were isolated from the leaves of the Vietnamese mangrove Aegiceras corniculatum. Their structures were determined by spectroscopic methods such as 1D and 2D NMR and HR-ESI-MS. The cytotoxic activities of the isolated compounds against MCF7 (breast), HCT116 (colon), B16F10 (melanoma), and A549 (adenocarcinoma) cancer cell lines were also evaluated. Strong cytotoxicity was observed for sakurasosaponin (2) against all four cancer cell lines and for sakurasosaponin methyl ester (3) against MCF7, A549, and HCT116 cell lines with IC₅₀ values ranging from 2.89 ± 0.02 to 9.86 ± 0.21 μM.     

Pleiocarpumlignan A,a new dineolignan from Piper pleiocarpum Chang ex Tseng

Abstract

The investigation of chemical constituents from the whole plants Piper pleiocarpum Chang ex Tseng resulted in the isolation of one new dineolignan, pleiocarpumlignan A (1), along with one known benzoate derivative, trans-2,3-diacetoxy-1-[(benzoy1oxy)methyl]-cyclohexa-4,6-diene (2), and two known neolignans (3–4) as (±)-trans-dehydrodiisoeugenol (3), (7R,8R,3′S)-△^8′-3′,6′-dihydro-3′-methoxy-3,4-methylenedioxy-6′-oxo-8,3′,7,O,4′-lignan (4). Their structures were elucidated through extensive spectroscopic analyses including 1D, 2D NMR, HR-ESI-MS, and by comparison with the literature. All compounds (1–4) were firstly isolated from Piper pleiocarpum Chang ex Tseng. The ¹³C NMR spectra of 2 were completely assigned for the first time. Cytotoxic activities of these isolated compounds against five human cancer cell lines (including A-549, SMMC-7721, HL-60, MCF-7, and SW-480) were evaluated.     

Bromine-containing alkaloids from the marine sponge Penares sp.

Two new unusual alkaloids were isolated from the sponge Penares sp., collected from Viet Nam waters (the South China Sea). The structures of these compounds were established by analysis of 1D, 2D NMR (¹H-¹H COSY, DEPT, HSQC, HMBC, H2BC, and NOE), and MS data. Compound 1 shows moderate cytotoxicity against the human tumor cells HL-60 and HeLa.     

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.     

Chemical constituents from rauvolfia verticillata and bioactivities research

A new acridone alkaloid, named 9-hydroxynoracronycine (1), together with four known compounds, including coumarins, lignan, and indole alkaloid, was isolated and identified from the roots and rhizomes of Rauvolfia verticillata. The structure of the new compound was determined by spectroscopic means (UV, IR, MS, and NMR). The acridone alkaloid and coumarins were identified as new constituents of Rauvolfia genus. The cytotoxic activities of the new compound were tested against human breast cancer cell line MCF-7 and human promyelocytic leukemia HL-60. Results showed that compound 1 decreased MCF-7 cell proliferation in a statistically IC₅₀ significant manner at 102.8 μmol/L. In addition, compound 1 exhibited moderate small intestine smooth muscle relaxation.     

Cytotoxic phenolic glycosides from <Emphasis Type="Italic">Boschniakia himalaica</Emphasis>

A new lignan glycoside, 9-acetyl lanicepside B (1), was isolated from the whole plant of Boschniakia himalaica, along with five known compounds, lanicepside A (2), plantainoside D (3), plantamajoside (4), (–)-woonenoside XI (5), and syringin (6). The new compound's structure was established on the basis of detailed 1D and 2D NMR spectroscopic analysis and chemical evidence. 9-Acetyl lanicepside B (1) showed weak in vitro cytotoxic activities against A549 and P388 with IC₅₀ values of 64.7 μM and 72.5 μM, respectively. Syringin (6) showed moderate in vitro cytotoxic activities against A549 and HL-60 with IC₅₀ values of 32.5 μM and 41.8 μM, respectively.     

A new galloyl glycoside from Lotus corniculatus

A new galloyl glucoside, 2,6-di-O-acetyl 1-O-galloyl β-D-glucose (1), along with five known phenolic compounds were isolated from the whole plants of Lotus corniculatus. Their structures were elucidated by means of extensive spectroscopic analysis. Compound 1 was assessed for its cytotoxicity against five human tumour lines (HL-60, SMMC-7721, A-549, MCF-7 and SW-480), and the result showed that it had no activity.