Stability and Photoisomerization of Stilbenes Isolated from the Bark of Norway Spruce Roots.

Stilbenes or stilbenoids, major polyphenolic compounds of the bark of Norway spruce ( L. Karst), have potential future applications as drugs, preservatives and other functional ingredients due to their antioxidative, antibacterial and antifungal properties. Stilbenes are photosensitive and UV and fluorescent light induce to isomerisation via intramolecular cyclization.

Bioactive Properties of the Aqueous Extracts of Endophytic Fungi Associated with Scots Pine (Pinus sylvestris) Roots.

Despite the continuing interest in various plant and natural products, only a small portion of the biologically active compounds from nature has been discovered and exploited. In this study, antioxidant and antibacterial properties of aqueous fractions of three endophytic fungi isolated from the roots of 8-year-old Scots pines () growing on a drained peatland were investigated. The endophytic fungi species were , and /.

Evaluation of Organo [F]Fluorosilicon Tetrazine as a Prosthetic Group for the Synthesis of PET Radiotracers.

Fluorine-18 is the most widely used positron emission tomography (PET) radionuclide currently in clinical application, due to its optimal nuclear properties. The synthesis of F-labeled radiotracers often requires harsh reaction conditions, limiting the use of sensitive bio- and macromolecules as precursors for direct radiolabeling with fluorine-18. We aimed to develop a milder and efficient in vitro and in vivo labeling method for trans-cyclooctene (TCO) functionalized proteins, through the bioorthogonal inverse-electron demand Diels-Alder (IEDDA) reaction with fluorine-18 radiolabeled tetrazine ([F]SiFA-Tz).

Novel Sulfonanilide Inhibitors of SHIP2 Enhance Glucose Uptake into Cultured Myotubes.

A series of substituted sulfonanilide analogs were prepared and evaluated as novel potent inhibitors of SH2 domain-containing inositol polyphosphate 5'-phosphatase 2 (SHIP2). SHIP2 has been shown to be a new attractive target for the treatment of insulin resistance in type 2 diabetes mellitus (T2D), which can lead to life-threatening diabetic kidney disease (DKD). Amongst the synthesized compounds, the two most promising candidates, and , inhibited SHIP2 significantly.

Molecular interactions between sex hormone-binding globulin and nonsteroidal ligands that enhance androgen activity.

Sex hormone-binding globulin (SHBG) determines the equilibrium between free and protein-bound androgens and estrogens in the blood and regulates their access to target tissues. Using crystallographic approaches and radiolabeled competitive binding-capacity assays, we report here how two nonsteroidal compounds bind to human SHBG, and how they influence androgen activity in cell culture. We found that one of these compounds, (-)3,4-divanillyltetrahydrofuran (DVT), present in stinging nettle root extracts and used as a nutraceutical, binds SHBG with relatively low affinity.

Correction: Tienaho, J., Metabolic Profiling of Water-Soluble Compounds from the Extracts of Dark Septate Endophytic Fungi (DSE) Isolated from Scots Pine ( L.) Seedlings Using UPLC-Orbitrap-MS. 2019, , 2330.

The authors wish to make the following corrections to this paper published in [...

Metformin increases glucose uptake and acts renoprotectively by reducing SHIP2 activity.

Metformin, the first-line drug to treat type 2 diabetes (T2D), inhibits mitochondrial glycerolphosphate dehydrogenase in the liver to suppress gluconeogenesis. However, the direct target and the underlying mechanisms by which metformin increases glucose uptake in peripheral tissues remain uncharacterized. Lipid phosphatase Src homology 2 domain-containing inositol-5-phosphatase 2 (SHIP2) is upregulated in diabetic rodent models and suppresses insulin signaling by reducing Akt activation, leading to insulin resistance and diminished glucose uptake.

On the Mechanism of the Reactivity of 1,3-Dialkylimidazolium Salts under Basic to Acidic Conditions: A Combined Kinetic and Computational Study.

Comprehensive spectroscopic kinetic studies illustrate an alternative mechanism for the traditional free-carbene intermediated H/D exchange reaction of 1,3-dialkylimidazolium salts under neutral (D O) and acidic conditions (DCl/D O 35 wt % solution). The deuteration of high purity [bmim]Cl in D O is studied at different temperatures, in absence of catalyst or impurities, to yield an activation energy. DFT transition-state modelling, of a small water cluster and [bmim] cation, also yields an activation energy which strongly supports the proposed mechanism.

Consumption of chokeberry (Aronia mitschurinii) products modestly lowered blood pressure and reduced low-grade inflammation in patients with mildly elevated blood pressure.

Previous studies suggest that consumption of chokeberries may improve cardiovascular disease risk factor profiles. We hypothesized that chokeberries (Aronia mitschurinii) have beneficial effects on blood pressure, low-grade inflammation, serum lipids, serum glucose, and platelet aggregation in patients with untreated mild hypertension. A total of 38 participants were enrolled into a 16-week single blinded crossover trial.

Plasma equol concentration is not associated with breast cancer and fibrocystic breast conditions among women in Shanghai, China.

Equol (a bacterial metabolite of the soy isoflavone daidzein) is produced by 30% to 50% of humans and may be associated with health outcomes. We hypothesized that plasma equol would be inversely associated with risks of fibrocystic breast conditions (FBC) and breast cancer (BC). Plasma from women in a breast self-examination trial in Shanghai with BC (n=269) or FBC (n=443), and age-matched controls (n=1027) was analyzed for isoflavones.

Synthesis of Tertiary and Quaternary Amine Derivatives from Wood Resin as Chiral NMR Solvating Agents.

Chiral tertiary and quaternary amine solvating agents for NMR spectroscopy were synthesized from the wood resin derivative (+)-dehydroabietylamine (2). The resolution of enantiomers of model compounds [Mosher's acid (3) and its n-Bu₄N salt (4)] (guests) by (+)-dehydroabietyl-N,N-dimethylmethanamine (5) and its ten different ammonium salts (hosts) was studied. The best results with 3 were obtained using 5 while with 4 the best enantiomeric resolution was obtained using (+)-dehydroabietyl-N,N-dimethylmethanaminium bis(trifluoromethane-sulfonimide) (6).

Synthesis and applications of secondary amine derivatives of (+)-dehydroabietylamine in chiral molecular recognition.

(+)-Dehydroabietylamine (1a), the novel derivatives (2a-6a) and their NTf2 salts (1b-6b) were tested as chiral NMR solvating agents for the resolution of enantiomers of the model compound Mosher's acid (7) and its n-Bu4N salt (8). Best enantiomeric discrimination of 7 was obtained using bisdehydroabietylamino-N(1),N(2)-ethane-1,2-diamine (6a), and of 8 using N-(dehydroabietyl)-2-(dehydroabietylamino)ethanaminium bis((trifluoromethyl)-sulfonyl)-amide (6b). For the maximal resolution of enantiomers of 8, 1.

Electrophilic Aromatic Deuteration of Lignans: Mostly Reliable but Occasionally Aberrant Selectivities.

Lignans are a ubiquitous group of natural products of plant or mammalian origin. In the human diet, especially in fiber-rich foods, there are measurable amounts of lignans. Lignan intake is associated with a reduced risk of a range of chronic Western diseases, and in studying these compounds and their biological activity, authentic stable isotope labeled analogues are needed.

Enterolignan-producing phenotypes are associated with increased gut microbial diversity and altered composition in premenopausal women in the United States.

Background: Lignans in plant foods are metabolized by gut bacteria to the enterolignans, enterodiol (END) and enterolactone (ENL). Enterolignans have biologic activities important to the prevention of cancer and chronic diseases. We examined the composition of the gut microbial community (GMC) as a contributor to human enterolignan exposure.

Capricious selectivity in electrophilic deuteration of methylenedioxy substituted aromatic compounds.

Ring deuteration via the SEAr mechanism, which is usually problem-free, is found to be troublesome with methylenedioxy substituent aromatics. We report a case where the deuteration not only partially fails at one of the ortho positions but also is completely prevented by a conformation dependent effect at the other o-position. Such selectivity discrepancies are important due to the widespread occurrence of methylenedioxy substituted natural products.

The orientation and dynamics of estradiol and estradiol oleate in lipid membranes and HDL disc models.

Estradiol (E2) and E2 oleate associate with high-density lipoproteins (HDLs). Their orientation in HDLs is unknown. We studied the orientation of E2 and E2 oleate in membranes and reconstituted HDLs, finding that E2 and E2 oleate are membrane-associated and highly mobile.

Rapid chemical characterisation of stilbenes in the root bark of Norway spruce by off-line HPLC/DAD-NMR.

Introduction: Stilbenes are plant secondary metabolites that have shown promising and varied biological activities. Stilbenes are presently actively studied for the exploitation of this primary raw material resource, involving the concept of biorefining. Methods for the rapid discovery of new and known stilbene structures from various plant sources are thus keenly sought.

Synthesis of 3,4-dibenzyltetrahydrofuran lignans (9,9'-epoxylignanes).

Different strategies for the racemic or enantiospecific total syntheses of plant and mammalian 3,4-dibenzyltetrahydrofuran lignans are reviewed and compared. The multi-step approaches have various key step strategies: Diels-Alder reactions, Stobbe condensations, Michael additions, alkylations, nitrile oxide cycloadditions, radical cyclisations, dianion and oxidative couplings.

Fatty acyl esterification and deesterification of 17β-estradiol in human breast subcutaneous adipose tissue.

Context: Adipose tissue has an important role in peripheral estrogen synthesis. One of the metabolic pathways of estradiol (E(2)) is its conversion to lipophilic fatty acyl esters.

Objective: The aim was to study the metabolism of E(2) fatty acyl esters in adipose tissue and, specifically, the role of hormone-sensitive lipase (HSL) in steroid ester hydrolysis.

Are there endogenous estrone fatty acyl esters in human plasma or ovarian follicular fluid?

Background: Estrone and its sulfated esters are the most abundant estrogens in blood in men and in women after the menopause. However, previous studies on the esterification of estrone with fatty acids have yielded conflicting results, some studies reporting high nanomolar concentrations of estrone fatty acyl esters in plasma.

Methods: We developed an estrone radioimmunoassay (RIA) method to determine endogenous concentrations of estrone and after saponification, applied it to male and female plasma.

Transcriptional activity of estrogen-related receptor γ (ERRγ) is stimulated by the phytoestrogen equol.

Estrogen-related receptor γ (ERRγ) is an orphan nuclear receptor lacking identified natural ligands. The synthetic estrogen receptor ligands 4-hydroxytamoxifen and diethylstilbestrol have, however, been shown to bind to and abolish the constitutive transcriptional activity of ERRγ. Certain phytoestrogens were recently reported to act as agonists of the related ERRα.

Enhanced chromatographic NMR with polyethyleneglycol. A novel resolving agent for diffusion ordered spectroscopy.

NMR analysis of complex mixtures can be significantly simplified using polyethyleneglycol (PEG) as resolving additive in DOSY NMR technique, which allows the extraction of individual spectra of mixture components with differing polarity. Resolving power of PEG-assisted DOSY was demonstrated with natural product mixtures.

Biomarkers of dietary exposure are associated with lower risk of breast fibroadenomas in Chinese women.

Fibroadenomas are the most common benign breast condition among women and account for up to 50% of all breast biopsies being performed. Although considered a benign condition, fibroadenomas utilize substantial resources for management and treatment to rule out potential malignancies. Dietary factors may influence benign fibrocystic breast conditions, but little is known of their association with fibroadenomas.

Rapid synthesis of long chain fatty acid esters of steroids in ionic liquids with microwave irradiation: expedient one-pot procedure for estradiol monoesters.

We report the rapid synthesis (1min) in high yield of fatty acid ester (FAE) derivatives of several steroids under microwave irradiation in an ionic liquid (IL). An expedient regioselective hydrolysis at C-3 of estradiol diesters is also reported.