DANSS is a highly segmented 1 m3 plastic scintillator detector. Its 2500 one meter long scintillator strips have a Gd-loaded reflective cover. The DANSS detector is placed under an industrial 3.1 ...GWth reactor of the Kalinin Nuclear Power Plant 350 km NW from Moscow. The distance to the core is varied on-line from 10.7 m to 12.7 m. The reactor building provides about 50 m water-equivalent shielding against the cosmic background. DANSS detects almost 5000 ν˜e per day at the closest position with the cosmic background less than 3%. The inverse beta decay process is used to detect ν˜e. Sterile neutrinos are searched for assuming the 4ν model (3 active and 1 sterile ν). The exclusion area in the Δm142,sin22θ14 plane is obtained using a ratio of positron energy spectra collected at different distances. Therefore results do not depend on the shape and normalization of the reactor ν˜e spectrum, as well as on the detector efficiency. Results are based on 966 thousand antineutrino events collected at three different distances from the reactor core. The excluded area covers a wide range of the sterile neutrino parameters up to sin22θ14<0.01 in the most sensitive region.
The review presents current data on the methods of synthesis and biological activity of purine-isosteric azolo-annulated 1,2,4-triazines and pyrimidines with a bridgehead nitrogen atom, which are ...among the most promising classes of biologically active compounds.
The DANSS detector (Alekseev et al. in JINST 11:P11011, 2016) is located directly below a commercial reactor core at the Kalinin Nuclear Power Plant. Such a position provides an overburden about 50 ...m.w.e. in vertical direction. In terms of the cosmic rays it occupies an intermediate position between surface and underground detectors. The sensitive volume of the detector is a cubic meter of plastic scintillator with fine segmentation and combined PMT and SiPM readout, surrounded by multilayer passive and active shielding. The detector can reconstruct muon tracks passing through its sensitive volume. The main physics goal of the DANSS experiment implies the antineutrino spectra measurements at various distances from the source. This is achieved by means of a lifting platform so that the data is taken in three positions – 10.9, 11.9 and 12.9 meters from the reactor core. The muon data were collected for nearly four calendar years. The overburden parameters
⟨
E
thr
cos
θ
⟩
and
⟨
E
thr
⟩
, as well as the temperature and barometric correlation coefficients are evaluated separately for the three detector positions and, in each position, in three ranges of the zenith angle – for nearly vertical muons with
cos
θ
>
0.9
, for nearly horizontal muons with
cos
θ
<
0.36
, and for the whole upper hemisphere.
This review is focused on the synthetic strategies to heterocyclic
C
-nucleosides and covers the literature from 2011 to 2021. The main attention is paid to the following three approaches: the direct ...C—C coupling of a carbohydrate moiety with a preformed aglycon unit, the construction of a (pseudo)sugar residue on a pre-formed aglycon, and the construction of an aglycon on a pre-formed (pseudo)sugar. In each Section, the literature data are categorized in terms of the size of aglycon from simple to complex, the advantages and drawbacks of the reviewed approaches are discussed.
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•Stable σ-adducts of azoloazines with polyphenols were synthesized.•The phloroglucinol-based compounds possessed the highest anti-influenza virus activity.•The compounds prevent ...binding of viral hemagglutinin with cellular receptor.
Stable σ-adducts of azolo5,1-ctriazines and azolo1,5-apyrimidines with different polyphenols were synthesized and their antioxidant and antiviral activity were investigated. Their affinity to viral hemagglutinin was assessed using molecular modelling. The phloroglucinol-modified azolo-azines possessed the highest virus-inhibiting activity. According to the results of the study of antioxidant properties of compounds, the most promising ones exhibiting highest antioxidant capacity were adducts containing in their structure pyrogallol and catechol residues and 6-nitro-triazolotriazin-7-ol scaffold. No correlation between antioxidant and virus-inhibiting activity of compounds studied was detected. The most active compounds demonstrated the ability to prevent binding of viral hemagglutinin with cellular receptor as shown in hemagglutination inhibition assay. Our results demonstrate that polyphenol-modified azolo-azines are prospective for further optimization as potential antivirals and that their action is directed against viral hemagglutinin.
Regulation of post-transcriptional gene expression by microRNAs (miRNA) has so far been validated for only a few mRNA targets. Based on the large number of miRNA genes and the possibility that one ...miRNA might influence gene expression of several targets simultaneously, the quantity of ribo-regulated genes is expected to be much higher. Here, we describe the web tool MicroInspector that will analyse a user-defined RNA sequence, which is typically an mRNA or a part of an mRNA, for the occurrence of binding sites for known and registered miRNAs. The program allows variation of temperature, the setting of energy values as well as the selection of different miRNA databases to identify miRNA-binding sites of different strength. MicroInspector could spot the correct sites for miRNA-interaction in known target mRNAs. Using other mRNAs, for which such an interaction has not yet been described, we discovered frequently potential miRNA binding sites of similar quality, which can now be analysed experimentally. The MicroInspector program is easy to use and does not require specific computer skills. The service can be accessed via the MicroInspector web server at http://www.imbb.forth.gr/microinspector.
Fused azoloazines with antidiabetic activity Rusinov, V. L.; Sapozhnikova, I. M.; Spasov, A. A. ...
Russian chemical bulletin,
12/2022, Letnik:
71, Številka:
12
Journal Article
Recenzirano
The purpose of this review is to summarize drugs containing an azoloazine moiety and exhibiting antidiabetic activity. The review includes azoloazines active against dipeptidyl peptidase-4, ...α-glucosidase, and glycogen phosphorylase acting as PPARγ and GPR119 receptor agonists, as well as those inhibiting advanced glycation.
The possibility of generating a carbanion using the reaction of 3-bromo-5,7-dimethylpyrazolo1,5-
a
pyrimidine with Bu
n
Li followed by the electrophilic addition was investigated. The obtained ...results provide evidence for the presence of several reaction centers in the substrate, resulting in the formation of unexpected reaction products. These results offer new prospects for the functionalization of pyrazolo1,5-
a
pyrimidines and allow the preparation of new pharmacologically active derivatives of this series. The structures and purity of all the synthesized compounds were confirmed by
1
H and
13
C NMR spectroscopy, mass spectrometry, elemental analysis, and X-ray crystallography.
6-Nitro-7-(4'-nitrophenyl)-5-ethyl-4,7-dihydropyrazolo1,5-
a
pyrimidine-3-carboxylate
(1)
is one of promising antitumor compounds exhibiting biological activity against type 2 casein kinase, which is ...currently considered as a promising target in chemotherapy. Using the method of cyclic voltammetry, it was shown that the electrochemical activity of compound
1
in a mixed solution of Tris-HCl and ethanol (1 : 1) at pH 7.5 on a glassy-carbon electrode is due to the electrochemical reduction of the nitro group conjugated with the phenyl ring. A method was developed for the determination of compound
1
by direct cathodic square-wave voltammetry. The linearity region of the corresponding calibration curve obtained in a solution of a mixture of Tris-HCl and ethanol (1 : 1) at pH 7.5 is 5–500 mg/L (
R
2
= 0.988), the limit of detection is 0.8 mg/L, the limit of quantification is 2.4 mg/L. The accuracy of the developed procedure is close to 100%, the relative standard deviation is 1.4%.