Three new phloroglucinol derivatives from Hypericum scabrum

A chemical investigation on the aerial parts of Hypericum scabrum L. resulted in the isolation of three new phloroglucinol derivatives, hyperscabrins A (1), B (2), and C (3), together with one known compound, (2R,3R,4S,6R)-3-methyl-4,6-di(3-methyl-2-butenyl)-2-(2-methyl-1-oxopropyl)-3-(4-methyl-3-pentenyl)-cyclohexanone (4). The structures were elucidated by means of spectroscopic methods, including MS, IR, 1D NMR, and 2D NMR, and the absolute configurations of chiral centers in these phloroglucinol derivatives were determined for the first time by studying their circular dichroism spectra.     

Chemical constituents from Piper hainanense and their cytotoxicities

Two new compounds, (Z,R)-1-phenylethylcinnamate (1) and (1R,2R,3R,6S)-pipoxide (2) were isolated from the aerial part of Piper hainanense, along with 12 known compounds, including nine benzene derivatives (4–11), one isobutylamide (12), and two polyoxygenated cyclohexene derivatives (13–14). Their structures were elucidated on the basis of the HRESIMS, 1D and 2D NMR spectroscopic analyses, and ECD in cases of 2 and 3. The absolute configuration of ellipeiopsol B (3) was determined for the first time. All these compounds 1–14 were reported from the titled plant for the first time. Most of the isolates were tested for their cytotoxicities against five human cancer cell lines. Four of which, 2, 3, 9, 14 showed moderate bioactivities. Among them, the new compound 2 showed potential cytotoxicity against SMMC-7721, MCF-7, and SW-480 with IC₅₀ values of 9.7, 15.0, and 13.2 μM, respectively.     

Stilbene and dihydrophenanthrene derivatives from <Emphasis Type="Italic">Pholidota chinensis</Emphasis> and their nitric oxide inhibitory and radical-scavenging activities

Two new stilbene derivatives, (E)-2′,3,3′-trihydroxy-5-methoxystilbene (1, Pholidotol C) and (Z)-3,3′-hydroxy-5-methoxystilbene (2, Pholidotol D), were isolated from the air-dried whole plant of Pholidota chinensis Lindl., together with eight known dihydrophenanthrene derivatives, lusianthridin (3), cannabidihydrophenanthrene (4), coelonin (5), hircinol (6), erianthridin (7), 4,5-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (8), eulophiol (9), and 2,4,7-trihydroxy-9,10-dihydrophenanthrene (10), and a benzoxepin derivative bulbophylol B (11). Their inhibitory effects on nitric oxide (NO) production activity and 1,1-diphenyl-2-picrylhydrazil radical-scavenging activity were examined. Among these compounds, 11 exhibited the most potent activity toward NO production inhibition activity and radical-scavenging activity; moreover, 11 reduced inducible nitric oxide synthase mRNA expression.     

Three new polyketides from Ascotricha sp. ZJ-M-5 by the OSMAC strategy

Three new compounds, ascotrichols A-B (1–2) and ascotrichrone A (3), along with two known isocoumarin derivatives (4–5), were isolated from the solid culture of a sea mud-derived fungus, Ascotricha sp. ZJ-M-5 on rice media. The structures were elucidated by extensive spectroscopic analyses, including 1D and 2D NMR data, and the absolute configurations were determined by electronic circular dichroism and biogenetic correlation.     

One new ergostane-type steroid and three new phthalide derivatives from cultures of the basidiomycete Albatrellus confluens

One new ergostane-type steroid, (12β,15β,22R,23S,24S)-22,25-epoxy-12,15,23-trihydroxyergost-4,6,8(14)-trien-3-one (1), three new phthalide derivatives, 5-(2′,3′-epoxy-3′,3′-dimethylpropoxy)-7-methoxy-6-methylphthalide (2), (2′)-(Z)-5-(3′-hydroxymethyl-3′-methylallyloxy)-7-methoxy-6-methylphthalide (3), and 5-(3′,3′-dimethylallyloxy)-7-hydroxy-6-methylphthalide (4), along with one known phthalide derivative, 5-(3′,3′-dimethylallyloxy)-7-methoxy-6-methylphthalide (5), were isolated from cultures of the basidiomycete Albatrellus confluens. The structures of the new compounds were established on the basis of extensive spectroscopic data (IR, MS, 1D, and 2D NMR) analyses. All compounds were evaluated for their cytotoxic activities on five tumor cell lines.     

Pharmacological evaluation of C-3 modified Betulinic acid derivatives with potent anticancer activity

Summary In vitro and in vivo pharmacological screening of Betulinic acid (BA) and five dihydro-BA derivatives modified at C-3 position [4-nitrobenzyl-oximino (1), 2-4-difluoro-benzoyloxy (2), 2-4-difluoro-benzylidene-amino (3), benzoyl-hydrazono (4), and 4-fluorophenyl-hydrazono (5)], having potent in vitro anti-cancer activity was carried out using ADME, animal PK and tumor studies. We found that BA and the derivatives had poor aqueous solubility (<0.1 μg/ml), low to moderate permeability (log Pe < −5.0) and high plasma protein binding (>70%). Although BA and 5 were metabolized by human liver microsomes, derivatives 1, 2, 3 and 4 possessed good in vitro metabolic stability. Except 3 which inhibited CYP1A2 isoform by more than 50% none of the other compounds inhibited key cytochrome P450 enzyme isoforms (CYP1A2, CYP2C9, CYP2D6 and CYP3A4) at 10 μM. Based on in vitro results one derivative 1 was tested in rodent PK and tumor studies. We found that 1 exhibited favorable pharmacokinetic characteristics of a systemically administered drug and showed better in vivo anti-tumor efficacy as compared to BA in a human colon cancer xenograft model. Our results show that BA derivatives are potential anti-cancer compounds which need to be explored in detail.     

Two new phenol derivatives from Stereum hirsutum FP-91666

Two new phenol derivatives, 2-(3-methyl-2-buten-1-yl)-4-methoxyethyl-phenol (1) and 5-hydroxy-4-(hydroxymethyl)-2-(3-methylbut-2-en-1-yl)cyclohex-4-en-1-one (2), together with eight known compounds consisting of phenol derivatives (3 and 4), niacinamide (5), and five ergosta type compounds (6–10), were isolated from solid fermentation products of Stereum hirsutum FP-91666. Two new structures were elucidated by extensive spectroscopic methods, including 1D NMR and 2D NMR, and HR-EI-MS experiments.     

Trichodermatides E and F from fungus Trichoderma applanatum

Two new polyketide derivatives, trichodermatides E (1) and F (2), are unprecedented examples of a polyketide with 6/6/6/6 tetracyclic skeleton, together with five known analogs koninginin B (3), koninginin D (4), 7-O-methylkoninginin D (5), koninginins E and F (6–7), were isolated from the plant endophytic fungus Trichoderma applanatum. The structures of these two compounds were determined by NMR data and HR-ESI-MS analysis. The putative biosynthesis of compounds 1–7 was presented.     

Thymol derivatives fromCarpesium divaricatum

Four thymol derivatives, 2,5-dimethoxythymol (1), 2-methoxythymol isobutyrate (2), 10-isobutyloxy-8,9-epoxythymolisobutyrate (3) and 10-(2-methylbutyloxy)-8,9-epoxythymolisobutyrate (4) were isolated from the aerial parts ofCarpesium divaricatum. The structures were elucidated by high field 1D and 2D NMR techniques.     

A new menthane-type monoterpenoid from fermented Illigera aromatica with Clonostachys rogersoniana 828H2

A new menthane-type monoterpenoid, illigerate E (1), as well as two known ones, (1R^*,3R^*,4S^*,6R^*)-6,8-dihydroxymenthol (2) and cis-4-hydroxy-5-(1-hydroxy-1-methylethyl)-2-methyl-2-cyclohexene-1-one (3), were isolated from fermented Illigera aromatica with Clonostachys rogersoniana 828H2. Their structures were identified by HRESIMS and 1D/2D NMR spectra. Their inhibitory effects of NO production in RAW 264.7 macrophages were estimated.     

Metabolites from endophytic fungus S20 of Cephalotaxus hainanensis

Three new C-methylated acetogenins, (2E,6Z)-9,10-dihydroxy-4-hydroxymethyl-2,6-decadiene (1), (2E,6Z)-8,9,10-trihydroxy-4-hydroxymethyl-2,6-decadiene (2), and (2E,6Z)-9-hydroxy-4-hydroxymethyl-2,6-nonadiene (3), together with two known compounds, p-hydroxybenzyl alcohol (4) and indolyl-3-carboxylic acid (5), were isolated from endophytic fungus S20 of Cephalotaxus hainanensis Li. Their structures were determined based on HR-ESI-MS and spectroscopic techniques (IR, UV, 1D, and 2D NMR). Compound 5 showed inhibitory effects on Staphylococcus aureus and methicillin-resistant S. aureus by the filter paper disc agar diffusion method.     

Qinanmer,a new compound from Chinese agarwood ‘Qi-Nan’ originating from Aquilaria sinensis

Qinanmer (1), a new compound comprising 2-(2-phenylethyl)chromone and sesquiterpene moieties, together with two known 2-(2-phenylethyl)chromone derivatives (2–3), was isolated from the high-quality Chinese agarwood “Qi-Nan” originating from Aquilaria sinensis (Lour.) Glig. The structure of 1 was elucidated by spectroscopic techniques (UV, IR, 1D and 2D NMR), MS analyses, ECD spectra analyses, and quantum ¹³C NMR calculations.     

Two new casbane diterpenoids from the roots of Euphorbia pekinensis

From the roots of Euphorbia pekinensis, two new casbane diterpenoids, named pekinenins A (1) and B (2), were isolated. Their structures were elucidated as 18-hydroxy-1βH,2αH-casba-3E,7E,11E-trien-5-one (1), 5α-methoxy-1βH,2αH-casba-3Z,7E,11E-trien-18-oic acid (2) by a combination of 1D and 2D NMR spectroscopy and mass spectrometry. In the cytotoxicity assay of the two new compounds against Hela, MCF-7, and C6 human cancer cell lines, compound 1 showed moderate cytotoxic activity against two human cancer cell lines, Hela and C6, with IC₅₀ values of 42.97 and 50.00 μM, respectively.     

Two new terpenoids from the stems of Manihot esculenta

A new eremophilane sesquiterpene, sporogen AO-2 (1), and a new beyerane diterpene, thecacorin C (2), together with two known compounds, longifoamide-B (3) and methylcholestane-3β,5α,6β-triol (4), were isolated from the stems of Manihot esculenta. The structures of the two new compounds were determined by spectroscopic techniques (UV, IR, MS, 1D, and 2D NMR). Antimicrobial assay showed that compound 3 possessed modest inhibitory effects on Saphylococcus aureus and methicillin-resistant S.aureus, diameters of inhibition zones of which were 7.5 and 8.0 mm, respectively. Compound 4 possessed modest inhibitory effect on S. aureus, the diameter of inhibition zone of which was 6.8 mm.     

Two new compounds from Atractylodes macrocephala with neuroprotective activity

In the present study, two new compounds, together with six known compounds, were isolated from rhizome of Atractylodes macrocephala Koidz by a series of silica gel, ODS column chromatography, and preparative HPLC. Their structures were characterized as atractylenolide II (1), atractylenolide I (2), biepiasterolid (3), isoatractylenolide I (4), atractylenolide III (5), 3β-acetoxyl atractylenolide I (6), (4E,6E,12E)-tetradeca-4,6,12-triene-8,10-diyne-13,14-triol (7), (3S,4E,6E,12E)-1-acetoxy-tetradeca-4,6,12-triene-8,10-diyne-3,14-diol (8) on the basis of 1D, 2D NMR, and circular dichroism analyses. Among them, compounds 6 and 8 were novel compounds. In addition, their neuroprotective activity against MPP⁺-induced SH-SY5Y cells was evaluated by MTT colorimetry. The results showed that all these compounds have definite protective effect on MPP⁺-induced SH-SY5Y cells.     

Two new dendrocandins with neurite outgrowth-promoting activity from Dendrobium officinale

Two new bibenzyl derivatives, dendrocandin T (1) and dendrocandin U (2), together with eight known bibenzyls, were isolated from the stems of Dendrobium officinale. Those compounds were sent for the first time for central nervous system-related bioassay and the results indicated that compounds 3, 4, and 5 have a certain degree of neurite outgrowth-promoting activity, and compounds 1, 2, 6, and 7 also have weak activity. The results indicated that D. officinale used as health food and traditional Chinese medicine “Tiepi Shihu” has a health function of neurotrophic effects.     

Phenolic constituents of <Emphasis Type="Italic">Acorus gramineus</Emphasis>

The purification of a MeOH extract from the rhizome of Acorus gramineus (Araceae) using column chromatography furnished two new stereoisomers of phenylpropanoid, acoraminol A (1) and acoraimol B (2). It also furnished 17 known phenolic compounds, β-asarone (3), asaraldehyde (4), isoacoramone (5), propioveratrone (6), (1′R,2′S)-1′,2′-dihydroxyasarone (7), (1′S,2′S)-1′,2′-dihydroxyasarone (8), 3′,4′-dimethoxycinnamyl alcohol (9), 3′,4′,5′-trimethoxycinnamyl alcohol (10), kaempferol 3-methyl ether (11), 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-propanediol (12), hydroxytyrosol (13), tyrosol (14), (2S,5S)-diveratryl-(3R,4S)-dimethyltetrahydrofuran (15), (7S,8R)-dihydrodehydrodiconiferyl alcohol (16), 7S,8S-threo-4,7,9,9′-tetrahydroxy-3,3′-dimethoxy-8-O-4′-neolignan (17), 7S,8R-erythro-4,7,9,9′-tetrahydroxy-3,3′-dimethoxy-8-O-4′-neolignan (18), and dihydroyashsbushiketol (19). The structures of the new compounds were elucidated by analysis of spectroscopic data including 1D and 2D NMR data. The absolute configurations of 1 and 2 were determined using the convenient Mosher ester procedure. Compounds 5–19 were isolated for the first time from this plant source. The isolated compounds were tested for cytotoxicity against four human tumor cell lines in vitro using a Sulforhodamine B (SRB) bioassay.     

2H-Pyranone and isocoumarin derivatives isolated from the plant pathogenic fungus Leptosphaena maculans

Abstract

Two new 2H-pyranones and two new isocoumarin derivatives, maculanslines A-D (1–4), together with seven known compounds (5–11), were isolated from the plant pathogenic fungus Leptosphaena maculans. Their planar structures and absolute configuration were elucidated by comprehensive spectroscopic techniques including high-resolution electrospray ionization mass spectrum, 1D and 2D nuclear magnetic resonance, as well as electronic circular dichroism. All 11 compounds were tested for their inhibitory activity against α-glucosidase. Compound 1 showed moderate inhibitory activity against α-glucosidase with IC₅₀ of 74.35 μM.     

Hydrolysis of timosaponin BII by the crude enzyme from Aspergillus niger AS 3.0739

Timosaponin BII (1), a steroidal saponin showing potential anti-dementia activity, was regioselectively hydrolyzed into its deglycosyl derivatives by the crude enzyme from Aspergillus niger AS 3.0739. Three biotransformation products, timosaponin BII-a (2), timosaponin BII-b (3), and timosaponin BII-c (4), were purified and their structures were elucidated on the basis of 1D NMR, 2D NMR, FAB-MS, and HR-ESI-MS spectral data. Compounds 2 and 3 are new compounds.     

Cytotoxic activity of flavonoids from the flowers of Chrysanthemum morifolium on human colon cancer Colon205 cells

A new p-hydroxyphenylacetyl flavonoid, diosmetin 7-(6″-O-p-hydroxyphenylacetyl)-O-β-d-glucopyranoside (1), was isolated from the flowers of Chrysanthemum morifolium Ramat. ‘huaiju’ cv. nov. (Compositae), together with five known flavonoids, luteolin (2), diosmetin (3), diosmetin 7-O-β-d-glucopyranoside (4), diosmin (5), and scolimoside (6), and four known caffeoylquinic acid derivatives, macranthoin F (7), 3,5-dicaffeoylquinic acid (8), 1,3-dicaffeoyl-epi-quinic acid (9), and chlorogenic acid (10). The structure of 1 was elucidated by UV, IR, ESI-TOF-MS, 1D, and 2D NMR spectroscopic methods. Cytotoxic activity of compounds 1–5 against human colon cancer cell Colon205 was investigated using MTT assays. Compounds 2 and 3 showed significant cytotoxicities against Colon205, with their IC₅₀ values being 96.9 and 82.9 μM, respectively. However, compounds 1, 4, and 5 showed little cytotoxic activity.