Bioassay-guided isolation of anti-leukemic steroids from Aglaia abbreviata by inducing apoptosis.

The strategy of bioactivity-guided isolation is widely used to obtain active compounds as quickly as possible. Thus, the inhibitory effects on human erythroleukemia cells (HEL) were applied to guide the isolation of the anti-leukemic compounds from Aglaia abbreviata. As a result, 19 compounds (16 steroids, two phenol derivatives, and a rare C12 chain nor-sesquiterpenoid), including 13 new compounds, were isolated and identified based on spectroscopic data analysis, single-crystal X-ray diffraction data, and electronic circular dichroism (ECD) calculations. Among them, 9 steroids exhibited good selective anti-leukemic activity against HEL and K562 (human chronic myeloid leukemia cells) cells with IC50 values between 2.29 ± 0.18 µM and 19.58 ± 0.13 µM. Notably, all the active compounds had relatively lower toxicity on the normal human liver cell line (HL-7702). Furthermore, five compounds (1, 4, 8, 10, and 19) displayed good anti-inflammatory effects, with IC50 values between 7.15 ± 0.16 and 27.1 ± 0.37 µM. An α,ß-unsaturated ketone or a 5,6Δ double bond was crucial for improving anti-leukemic effect from the structure-activity relationship analysis. The compound with the most potential, 14 was selected for the preliminary mechanistic study. Compound 14 can induce apoptosis and cause cell cycle arrest. The expression of the marker proteins, such as PARP and caspase 3, were notably effected by this compound, thus inducing apoptosis. In conclusion, our investigation implied that compound 14 may serve as a potential anti-leukemia agent.

Phytochemical study on ethyl acetate fraction of Lepidium obtusum Basin.

Three undescribed compounds (1-3), including two butenolides and one indol alkaloids. Together with twenty-one known compounds (4-24) were isolated and identified from Lepidium obtusum Basin. Their structures were elucidated by spectroscopic analysis and ECD calculations. The isolated compounds were tested for their antimicrobial, antioxidant, and anti-inflammatory activities. Among them, compounds 11, 12, 14, 21 and 23 showed moderated antimicrobial activities against (Candida albicans, E. coli, Staphylococcus aureus). Compounds 11, 12, 14, 15, 17 and 18 exhibited potent antioxidant activities against ABTS and DPPH. Compound 1 exhibited moderated anti-inflammatory activities. Compounds 4-24 were isolated from this plant for the first time.

Three new oxygenated yohimbane-type alkaloids from Ophiorrhiza japonica.

A series of oxygenated yohimbane alkaloids, including three new compounds, ophiorrhines H-J (1-3), and seven known compounds, were isolated from the aerial parts of Ophiorrhiza japonica. The structures with absolute configurations were elucidated by extensive MS and NMR spectroscopic methods, as well as the single crystal X-ray diffraction and ECD calculations. Ophiorrhines H (1) and I (2) represent key oxygenated intermediates in the formation of aromatic ring E in the demethoxycarbonyl-3,14-dihydrogambirtannine (10). Ophiorrhine J (3) is a highly oxidized yohimbane derivative with the planar superconjugated system. The cytotoxic activities of all alkaloids against five human cancer cell lines were evaluated.

Secondary Metabolites from Hericium erinaceus and Their Anti-Inflammatory Activities.

Hericium erinaceus, a culinary and medicinal mushroom, is widely consumed in Asian countries. Chemical investigation on the fruiting bodies of Hericium erinaceus led to the isolation of one new ergostane-type sterol fatty acid ester, erinarol K (1); and eleven known compounds: 5α,8α -epidioxyergosta-6,22-dien-3ß-yl linoleate (2); ethyl linoleate (3); linoleic acid (4); hericene A (5); hericene D (6); hericene E (7); ergosta-4,6,8(14),22-tetraen-3-one (8); hericenone F (9); ergosterol (10); ergosterol peroxide (11); 3ß,5α,6α,22E-ergosta-7,22-diene-3,5,6-triol 6-oleate (12). The chemical structures of the compounds were determined by 1D and 2D NMR (nuclear magnetic resonance) spectroscopy, mass spectra, etc. Anti-inflammatory effects of the isolated aromatic compounds (5-7, 9) were evaluated in terms of inhibition of pro-inflammatory mediator (TNF-α, IL-6 and NO) production in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophage cells. The results showed that compounds 5 and 9 exhibited moderate activity against TNF-α (IC50: 78.50 µM and 62.46 µM), IL-6 (IC50: 56.33 µM and 48.50 µM) and NO (IC50: 87.31 µM and 76.16 µM) secretion. These results supply new information about the secondary metabolites of Hericium erinaceus and their anti-inflammatory effects.

Insight into isolation and elucidation of cytotoxic ergostanoids from the mushroom Sarcosphaera crassa (Santi) Pouzar: An edible mushroom.

Sarcosphaera crassa is a mushroom consumed in Europe and Anatolia after being cooked well. The cytotoxic activity of the extracts of unbaked S. crassa against MCF7, HT29, HeLa cancer cell lines and toxicity against PDF fibroblast healthy cell lines were studied using MTT assay. Acetone and methanol extracts of the mushroom exhibited significant cytotoxic activity. Further investigation of cytotoxic extracts afforded two new fatty acid sterols (1-2), a new ergosterol glycoside (4), and seven known compounds, including a fatty acid sterol (3), a steroid glycoside (5), two ergostanoids (6-7) and three sugars (8-10). These compounds were identified as brassicasteryl heptadecanoate (1), brassicasteryl palmitoleate (2), brassicasteryl linoleate (3), brassicasterol ß-ᴅ-xylofuranoside (4), brassicasterol ß-ᴅ-glucoside (5), brassicasterol (6), ergosterol-endoperoxide (7), mannitol (8), erythritol (9) and turanose (10). Among them, 7 exhibited a moderate cytotoxic activity against HeLa (IC50: 70.1 ± 2.0 µg/mL) and high activity against HT29 (IC50: 38.8 ± 0.9 µg/mL), and MCF7 (IC50: 62.9 ± 1.3 µg/mL) cancer cell lines. Compounds 4, 5, and 6 also exhibited significant cytotoxic activity against HT29 and MCF7. Moreover, all compounds exhibited weak toxicity against PDF healthy cell lines. This study indicates the potential use of Sarcosphaera crassa as a natural source of cytotoxic ergostanoids, which can be considered a dietary supplement for cancer prevention.

Immunosuppressive Sesquiterpenoids from the Edible Mushroom Craterellus odoratus.

The aim of this work was to comprehensively understand the chemical constituents of the edible mushroom Craterellus ordoratus and their bioactivity. A chemical investigation on this mushroom led to the isolation of 23 sesquiterpenoids including eighteen previously undescribed bergamotane sesquiterpenes, craterodoratins A-R (1-18), and one new victoxinine derivative, craterodoratin S (19). The new structures were elucidated by detailed interpretation of spectrometric data, theoretical nuclear magnetic resonance (NMR) and electronic circular dichroism (ECD) calculations, and single-crystal X-ray crystallographic analysis. Compounds 1 and 2 possess a ring-rearranged carbon skeleton. Compounds 3, 10, 12-15, 19, 20 and 23 exhibit potent inhibitory activity against the lipopolysaccharide (LPS)-induced proliferation of B lymphocyte cells with the IC50 values ranging from 0.67 to 22.68 µM. Compounds 17 and 20 inhibit the concanavalin A (ConA)-induced proliferation of T lymphocyte cell with IC50 values of 31.50 and 0.98 µM, respectively. It is suggested that C. ordoratus is a good source for bergamotane sesquiterpenoids, and their immunosuppressive activity was reported for the first time. This research is conducive to the further development and utilization of C. ordoratus.

Indole alkaloids from Ophiorrhiza cantoniensis with immunosuppressive activity.

Three new indole alkaloids, ophiorrhines C-D (1-3), together with one known analogue, have been isolated from the plant of Ophiorrhiza cantoniensis Hace. The structures of the new alkaloids with the absolute configurations were elucidated by means of spectroscopic methods, electronic circular dichroism (ECD) and calculated nuclear magnetic resonance (NMR) with DP4+ analysis. Compounds 1 and 2 exhibited certain activity to Con-A induced T cell proliferation, and 1 exhibited good inhibition on LPS-induced B cell proliferation with an IC50 value of 8.7 µM.

Monoterpenoid indole alkaloids from the bark of Melodinus henryi.

Four new alkaloids, melodinines W1-W4 (1-4), together with twenty one known alkaloids (5-25) were isolated from Melodinus henryi. The structures with absolute configurations were elucidated by extensive MS and NMR spectroscopic methods, as well as the single crystal X-ray diffraction and ECD calculations. All compounds were evaluated for their cytotoxicities to five human cancer cell lines. Many compounds showed certain cytotoxicities to five human cancer cell lines with an IC50 range of 1.4-29.4 µM.

Two highly oxygenated Ergosterols from cultures of the Basidiomycete Conocybe siliginea.

Two highly oxygenated ergosterols, (22E,24R)-3ß,5α,6ß,9α,14α,25-hexhydroxyergosta-7,22-diene (1), and (22E,24R)-3ß,5α,6ß,14α,25-pentahydroxyergosta-7,9(11),22-triene (2), together with two known ones, have been isolated from cultures of the basidiomycete Conocybe siliginea. Their structures were elucidated on the basis of extensive spectroscopic means. Two new compounds (1 and 2) were tested for their nitric oxide synthase inhibitory activities. However, none of them showed any activity (IC50 > 40 µM).

Structural elucidation of gemifloxacin mesylate degradation product.

Gemifloxacin mesylate (GFM), chemically (R,S)-7-[(4Z)-3-(aminomethyl)-4-(methoxyimino)-1-pyrrolidinyl]-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid methanesulfonate, is a synthetic broad-spectrum antibacterial agent. Although many papers have been published in the literature describing the stability of fluorquinolones, little is known about the degradation products of GFM. Forced degradation studies of GFM were performed using radiation (UV-A), acid (1 mol L(-1) HCl) and alkaline conditions (0.2 mol L(-1) NaOH). The main degradation product, formed under alkaline conditions, was isolated using semi-preparative LC and structurally elucidated by nuclear magnetic resonance (proton - (1) H; carbon - (13) C; correlate spectroscopy - COSY; heteronuclear single quantum coherence - HSQC; heteronuclear multiple-bond correlation - HMBC; spectroscopy - infrared, atomic emission and mass spectrometry techniques). The degradation product isolated was characterized as sodium 7-amino-1-pyrrolidinyl-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylate, which was formed by loss of the 3-(aminomethyl)-4-(methoxyimino)-1-pyrrolidinyl ring and formation of the sodium carboxylate. The structural characterization of the degradation product was very important to understand the degradation mechanism of the GFM under alkaline conditions. In addition, the results highlight the importance of appropriate protection against hydrolysis and UV radiation during the drug-development process, storage, handling and quality control.