Inhibitory effects of candesartan on KCa3.1 potassium channel expression and cell culture and proliferation in peripheral blood CD4+T lymphocytes in Kazakh patients with hypertension from the Xinjiang region.

BACKGROUND AND AIM: Increasing evidence confirms that potassium channels are essential for lymphocyte activation, suggesting an involvement in the development of hypertension. Moreover, chronic inflammation is regarded as a direct or indirect manifestation of hypertension, highlighting the theoretical mechanisms. In this study, we investigated changes in KCa3.1 potassium channel expression in the blood of hypertensive and healthy Kazakh people in north-west China. METHODS: Flow cytometry technology was used for T-lymphocyte subtype analysis. Changes in the messenger RNA and protein expression of the KCa3.1 potassium channel in CD4+ T lymphocytes were detected using real-time quantitative polymerase chain reaction and western blots, using CD4+ T-cell samples from hypertensive Kazakh patients divided into candesartan and TRAM-34 treatment groups, and healthy case controls. Peripheral blood CD4+ T lymphocytes were activated and proliferated in vitro and then incubated for 0, 24, and 48 h under various treatment conditions. Changes in CD4+ T-lymphocytic proliferation were determined using Cell Counting Kit-8 and electron microscope photography. RESULTS: Expression of KCa3.1 was significantly higher in the hypertensive patients than in the controls (p < 0.05). Compared with the healthy group, Kazakh hypertensive patients had a reduced proportion of CD4+ T lymphocytes (p < 0.05).Candesartan and TRAM-34 intervention for 24 h and 48 h inhibited the expression of Kv1.3 and KCa3.1 at mRNA and protein level (p < 0.05). CONCLUSIONS: Increase in functional KCa3.1 channels expressed in CD4+ T lymphocytes of Kazakh patients with hypertension was blocked by candesartan, providing theoretical support for hypertension treatment at the cellular ion channel level. Candesartan may potentially regulate hypertensive inflammatory responses by inhibiting T-lymphocytic proliferation and KCa3.1 potassium channel expression in CD4 + T lymphocytes.

B(C6F5)3 catalyzed direct nucleophilic substitution of benzylic alcohols: an effective method of constructing C-O, C-S and C-C bonds from benzylic alcohols.

An efficient and general method of nucleophilic substitution of benzylic alcohols catalyzed by non-metallic Lewis acid B(C6F5)3 was developed. The reaction could be carried out under mild conditions and more than 35 examples of ethers, thioethers and triarylmethanes were constructed in high yields. Some bioactive organic molecules were synthesized directly using the methods.

Organocatalytic Friedel-Crafts Alkylation/Lactonization Reaction of Naphthols with 3-Trifluoroethylidene Oxindoles: The Asymmetric Synthesis of Dihydrocoumarins.

Naphthols and 3-trifluoroethylidene oxindoles were found to undergo an asymmetric Friedel-Crafts alkylation/lactonization reaction, catalyzed by only 2.5 mol % of a quinine-derived squaramide catalyst, to afford the corresponding α-aryl-ß-trifluoromethyl dihydrocoumarin derivatives in high yields (up to 99 %) with excellent enantio- and diastereoselectivities (up to 98 % ee, >20:1 d.r.). Importantly, the lactonization proceeded by nucleophilic attack of the naphthol hydroxy group at the amide motif of the oxindoles under mild reaction conditions. This protocol represents a new strategy for the formation of dihydrocoumarins by an efficient intramolecular amide C-N bond-cleavage and esterification process.

Allelopathic Polyketides from an Endolichenic Fungus Myxotrichum SP. by Using OSMAC Strategy.

Three new polyketides myxotritones A-C (2-4), together with a new natural product 7,8-dihydro-7R,8S-dihydroxy-3,7-dimethyl-2-benzopyran-6-one (1) were obtained from the endolichenic fungus Myxotrichum sp. by using OMSAC (One Strain, Many Compounds) method. The planar structures of these new compounds were determined by NMR experiment and HRESIMS data, and the absolute configuration of 1 was established by X-ray diffraction, and the stereochemistry of the new compounds 2-4 were determined by same biosynthesis origin, and similar CD spectra with 1. Allelopathic test showed that compound 4 significantly retarded root elongation of Arabidopsis thaliana seed, indicating that this fungus might contribute to the defense of its host lichen. From the view of biosynthetic pathway, all four compounds 1-4 might be originated from Non-Reduced Polyketide synthase (NR-PKS).

Chiral phosphoric acid catalyzed highly enantioselective Friedel-Crafts alkylation reaction of C3-substituted indoles to ß,γ-unsaturated α-ketimino esters.

A highly enantioselective C2 Friedel-Crafts alkylation reaction of 3-substituted indoles to ß,γ-unsaturated α-ketimino esters has been developed. This reaction was efficiently catalyzed by a chiral phosphoric acid catalyst. The corresponding C2-substituted indole derivatives, bearing an α-ketimino ester motif, were obtained in moderate to high yields (up to 93%) and with high enantioselectivities (up to >99% ee).

[Optimization of extraction of Clerodendranthus spicatus using response surface methodology].

OBJECTIVE: To obtain the optimal conditions of extraction of Clerodendranthus spicatus and provide the theoretical foundation for its further processing and utilization. METHODS: On the basis of the single factor test, response surface methodology was applied to optimize the extraction conditions. RESULTS: The results showed that extraction time, water-feed ratio, ethanol concentration and extraction temperature all had significant effects on the extraction rate of polysaccharides. The optimal extraction time was 3h, solid-liquid ratio was 50:1, ethanol concentration was 30% and extraction temperature was 80 degrees C. Under these optimized conditions, the extraction rate was 27.71%. CONCLUSION: The extraction technology is simple, reliable and highly predictive.

The structure, properties, and nature of HArF-HOX (X = F, Cl, Br) complex: an ab initio study and an unusual short hydrogen bond.

The structure and properties (geometric, energetic, electronic, spectroscopic, and thermodynamic properties) of HArF-HOX (X = F, Cl, Br) complex have been investigated at the MP2/aug-cc-pVTZ level. Three types of complexes are formed through a hydrogen bond or a halogen bond. The HArF-HOX complex is the most stable, followed by the FArH-OHX complex, and the HArF-XOH complex is the most unstable. The binding distance in FArH-OHX complex is very short (1.1-1.7 Å) and is smaller than that in HArF-HOX complex. However, the interaction strength in the former is weaker than that in the latter. Thus, an unusual short hydrogen bond is present in FArH-OHX complex. The associated H-Ar bond exhibits a red shift, whereas the distant one gives a blue shift. A similar result is also found for the O-H and O-X bonds. The isotropic chemical shift is negative for the associated hydrogen atom but is positive for the associated halogen atom. However, a reverse result is found for the anisotropic chemical shift. The analyses of natural bond orbital and atoms in molecules have been performed for these complexes to understand the nature and properties of hydrogen and halogen bonds.

Catalytic and highly enantioselective Friedel-Crafts alkylation of aromatic ethers with trifluoropyruvate under solvent-free conditions.

[Structure: see text] Highly enantioselective Friedel-Crafts alkylation of simple and aromatic ethers (4a-l) with 3,3,3-trifluoropyruvate (3) was accomplished by using chiral (4R,5S)-DiPh-BOX(1b)-Cu(OTf)2 complex (1 mol %) as a catalyst under solvent-free conditions. Excellent yields and enantioselectivities (90-93% ee, after recrystallization up to 99% ee) of the Friedel-Crafts alkylation products were obtained.