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1.
A number of samples of sodium and silver phosphate glasses doped with
various compositions of some transition metals viz. iron, manganese and zinc
chlorides alongwith undoped samples of sodium and silver phosphate glasses
were synthesized and characterized by X-ray diffraction, IR spectral, electrical
conductivity and differential scanning calorimetry (DSC). The glass transition
temperature (T
g)
and crystallization temperature (T
c)
values obtained from DSC curves were found to increase with increasing concentration
of the dopant Fe/Mn/Zn chlorides in both sodium and silver phosphate glasses
and the following sequence is observed:
T
g(–FeCl3)>T
g(–MnCl2)>T
g(–ZnCl2)
T
c(–FeCl3)>T
c(–MnCl2)>T
c(–ZnCl2)
The increase in T
g
and T
c values indicate
enhanced chemical durability of the doped glasses. The electrical conductivity
values and the results of FTIR spectral studies have been correlated with
the structural changes in the glass matrix by the addition of different transition
metal cations as dopants. 相似文献
2.
L. N. Yang F. Xu L. X. Sun Z. C. Tan H. D. Tan Z. B. Zhao J. G. Liang 《Journal of Thermal Analysis and Calorimetry》2006,85(3):807-810
A microcalorimetric
technique based on the bacterial heat output was applied to evaluate the influence
of antibiotics PIP (Piperacillin Sodium)
and composite preparation of PIP and SBT (Sulbactam
Sodium) on the growth of E. coli
DH5α. The power–time curves of the growth metabolism of E. coli DH5α were studied using a TAM Air Isothermal
Microcalorimeter at 37°C. By analyzing the power–time curves, the
parameters such as growth rate constants (k),
inhibitory ratio (I), the maximum heat
power (P
m) and the
time of the maximum heat power (t
m)
were obtained. The results show that different concentrations of antibiotics
affect the growth metabolism of E. coli
DH5α. The PIP in the concentration range of 0–0.05 μg mL–1
has a stimulatory effect on the E. coli
DH5α growth, while the PIP of higher concentrations (0.05 –0.25
μg mL–1) can inhibit its growth. It seems
that the composite preparation composed of PIP and SBT cannot improve the
inhibitory effect on E. coli DH5α
as compared with the PIP. 相似文献
3.
N. N. Sidamonidze L. K. Janiashvili R. O. Vardiashvili R. A. Gakhokidze 《Chemistry of Natural Compounds》2006,42(2):127-128
A new synthesis of certain lactam-containing N-glycosides was developed. 2,3,4,6-Tetra-O-acetyl-β-D-gluco(galacto)pyranosylcaprolactams and 2,3,4,6-tetra-O-acetyl-β-D-gluco(galacto)pyranosylpyrrolidones were synthesized by condensation at room temperature of acetobromoglucose and acetobromogalactose
with ɛ-caprolactams and α-pyrrolidone.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 105–106, March–April, 2006. 相似文献
4.
D. A. Panov V. I. Grishkovets V. V. Kachala A. S. Shashkov 《Chemistry of Natural Compounds》2006,42(1):61-66
Sixteen triterpene glycosides, three of which were new, hederagenin 28-O-β-D-glucuronopyranosyl ester and 28-O-β-D-gentiobiosyl ester and oleanolic acid 3-O-α-L-arabinopyranoside, were isolated from stem bark of Kalopanax septemlobum. The glycoside contents in stem bark of two varieties, maximowiczii and typicum, were compared.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 49–53, January–February, 2006. 相似文献
5.
L. E. Nikitina V. A. Startseva V. V. Plemenkov S. A. Dieva O. A. Lodochnikova I. A. Litvinov 《Chemistry of Natural Compounds》2007,43(3):263-267
A new type of S-containing terpene lactones was produced by the reactions of limonene-1,2-oxide and β-pinene-α-oxide with mercaptoacetic acid.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 220–223, May–June, 2007. 相似文献
6.
A (n, n + 1)-graph G is a connected simple graph with n vertices and n + 1 edges. In this paper, we determine the upper bound for the Merrifield–Simmons index in (n, n + 1)–graphs in terms of the order n, and characterize the (n, n + 1)–graph with the largest Merrifield–Simmons index. 相似文献
7.
Summary. Conformational analysis and frequency calculation were achieved for 1-phenyl-1,2-propandione 1-oxime and its four tautomers:
1-nitroso-1-phenyl-1-propen-2-ol, 1-nitroso-1-phenyl-2-propanone, 2-hydroxy-1-phenyl-propenone oxime, and 3-nitroso-3-phenyl-propen-2-ol.
Calculations were carried out at the Hartree–Fock (HF), Density Functional Theory (B3LYP), and the second-order M?ller–Plesset perturbation (MP2) levels of theory using 6-31G* and 6-311G** basis sets. Five conformers with no imaginary vibrational frequency were obtained by free rotations around three single bonds
of 1-phenyl-1,2-propandione-1-oxime: Ph–C(NOH)C(O)CH3, PhC(NOH)–C(O)CH3, and PhC(N–OH)C(O)CH3. Similarly, eight structures with no imaginary vibrational frequency were encountered upon rotations around three single
bonds of 1-nitroso-1-phenyl-1-propen-2-ol: Ph–C(NO)C(OH)CH3, PhC(N–O)C(OH)CH3, and PhC(NO)C(–OH)CH3. In the same manner, six minima were found through rotations around three single bonds of 1-nitroso-1-phenyl-2-propanone:
Ph–CH(NO)C(O)CH3, PhCH(–NO)C(O)CH3, and PhCH(NO)–C(O)CH3. Also, two minima were found through rotations around four single bonds of 2-hydroxy-1-phenyl-propenone oxime: Ph–C(NOH)C(OH)CH2, PhC(N–OH)C(OH)CH2, PhC(NOH)–C(OH)CH2, and Ph-C(NOH)C(–OH)CH2. Finally, two minima were found through rotations around four single bonds of 3-nitroso-3-phenyl-propen-2-ol: Ph–CH(NO)C(OH)CH2, PhCH(–NO)C(OH)CH2, PhCH(NO)–C(OH)CH2, and PhCH(NO)C(–OH)CH2. Interconversions within the above sets of conformers were probed through scanning (one and/or two dimensional), and/or QST3
techniques. The order of the stability of global minima encountered was: 1,2-propandione-1-oxime > 1-nitroso-1-phenyl-2-propanone
> 1-nitroso-1-phenyl-1-propen-2-ol > 2-hydroxy-1-phenyl-propenone oxime > 3-nitroso-3-phenyl-propen-2-ol. Hydrogen bonding
appears significant in tautomers of 1-nitroso-1-phenyl-1-propen-2-ol and 2-hydroxy-1-phenyl-propenone oxime. The CIS simulated
λmax for the first excited singlet state (S1) of 1-phenyl-1,2-propandione 1-oxime is 300.4 nm, which was comparable to its experimental λmax of 312.0 nm. The calculated IR spectra of 1-phenyl-1,2-propandione 1-oxime and its tautomers were compared to the experimental
spectra. 相似文献
8.
Yu. N. Belokon K. A. Kochetkov T. D. Churkina N. S. Ikonnikov A. A. Chesnokov O. V. Larionov H. V. Kagan 《Russian Chemical Bulletin》1999,48(5):917-923
It is shown that sodium alkoxides formed from (4R,5R)-2,2-dimethyl-1,3-dioxolane-4,5-bis(diphenylmethanol) ((R,R)-TADDOL) and some of its derivatives can be used as chiral catalysts for enantioselective alkylation of Schiff's bases derived
from alanine with reactive alkyl halides. Acid hydrolysis of the reaction products affords (R)-α-methylphenyl-alanine, (R)-α-allylalanine, and (R)-α-methylnaphthylalanine in 61–93% yields and withee 69–94%. When (S,S)-TADDOL is used, the (S)-amino acid is formed. A mechanism explaning the observed features of the reaction is proposed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 926–932, May, 1999. 相似文献
9.
Orrapat Pureesatien Chitchamai Ovatlarnporn Arunporn Itharat Ruedeekorn Wiwattanapatapee 《Chromatographia》2008,67(7-8):551-557
A reversed-phase high-performance liquid chromatographic method has been developed and validated for the determination of
pyridostemin, the major pesticidal alkaloid found in Stemona curtisii. This methodology was applied to the investigation of plant extracts and water dispersible granule formulations. Stability
indicating procedures have also been carried out. The chromatographic separation was on a C18 column with a mixture of acetonitrile–water–triethylamine (30:70:0.12, v/v/v), using UV detection at 300 nm. Validation procedures showed that the method was specific, accurate and precise. The response
was linear over a range of 5–25 μg mL−1 with recoveries in the range of 98.28–102.85%. The RSD for intra- and inter-day precision were <0.72 and <1.29%, respectively.
Extraction of plant material with dichloromethane gave a significantly higher pyridostemin content in the crude extracts when
compared with extractions in methanol. Partial purification of the crude extracts by silica gel column chromatography was
used to concentrate the mixture about fourfold. Degradation behavior of pyridostemin in the partially purified extracts followed
first-order kinetics. The main pathways for its decomposition were base hydrolysis and oxidation. 相似文献
10.
Xiaodong Jia Xingzeng Zhao Ming Wang Yu Chen Yunfa Dong Xu Feng 《Chemistry of Natural Compounds》2008,44(6):692-695
Two new coumarin biosides, tert-O-β-D-apiofuranosyl-(1→6)-O-β-D-glucopyranosyl-byakangelicin (1) and 2′-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranosyl-peucedanol (2), were isolated from the fresh roots of Angelica dahurica. The structures of the new compounds were elucidated on the basis of spectral analysis.
Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 561–563, November–December, 2008. 相似文献
11.
Kh. M. Shakhidoyatov G. P. Genjemuratova E. Oripov 《Chemistry of Natural Compounds》2006,42(6):718-723
The reaction of deoxyvasicinone with acid chlorides of aliphatic (acetylbromide) and aromatic (benzoyl-, o-, p-methoxy-, p-nitrobenzoylchlorides) acids was studied. It was shown that 1-deoxyvasicinone salts were formed at room temperature; α-aroyloxymethylidenedeoxyvasicinones, in the presence of triethylamine at 80–85°C. It was found that acid chlorides cause
1-acyldeoxyvasicinone salts to transform into α-hydroxy-or α-aroyloxyarylidenedeoxyvasicinones, which indirectly confirmed their acylating properties. It was found that 1-acyldeoxyvasicinone
salts were effective acylating agents for alkaloids (cytisine, 1,2-dihydrodeoxyvasicinone) and amino acids (glycine, β-alanine, α-aminobutyric acid) and can be used to acylate primary and secondary aliphatic and heterocyclic amines.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 585–589, November–December, 2006. 相似文献
12.
M. I. Merlani L. Sh. Amiranashvili N. I. Men’shova E. P. Kemertelidze 《Chemistry of Natural Compounds》2007,43(1):97-99
5α-Androstan-3β,17β-diol (3b-adiol), a known inhibitor of prostate cancer cell growth, was synthesized from tigogenin. Its structure was confirmed
by NMR and IR spectroscopy and mass spectroscopy.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 81–82, January–February, 2007. 相似文献
13.
Akram M. El-Didamony 《Central European Journal of Chemistry》2005,3(3):520-536
Three simple, accurate, and sensitive spectrophotometric methods (A, B and C) have been described for the indirect assay of
diltiazem hydrochloride (DIL.HCl), either in pure form or in pharmaceutical formulations. The first method (A) is based on
the oxidation of DIL.HCl by N-bromosuccinimide (NBS) and determination of unconsumed NBS by measuring the decrease in absorbance
of amaranth dye (AM) at a suitable λ
max
=521 nm. Other methods (B) and (C) involve the addition of excess cerric ammonium sulfate (CAS) and subsequent determination
of the unconsumed oxidant by a decrease in the red color of chromotrope 2R (C2R) at a suitable λ
max
=528 nm or a decrease in the orange-pink color of rhodamine 6G (Rh6G) at λ
max
=525 nm, respectively. Regression analysis of Beer-Lambert plots showed good correlation in the concentration ranges 3.0–9.0,
3.5–7.0 and 3.5–6.3 μg ml−1 for methods A, B and C, respectively. The apparent molar absorptivity, Sandell's sensitivity, detection and quantification
limits were calculated. The proposed methods have been applied successfully for the analysis of the drug in its pure form
and its dosage form. No interference was observed from a common pharmaceutical adjuvant. Statistical comparison of the results
with the reference method shows excellent agreement and indicates no significant difference in accuracy and precision. 相似文献
14.
B. B. Semenov K. A. Novikov V. V. Kachala V. N. Azev 《Chemistry of Natural Compounds》2006,42(5):582-584
The Pictet-Spengler reaction involving β-phenyltryptamine was shown to be diastereo-specific with formation primarily of the (1S*,4R*) diastereomer of 4-phenyl-1-(2-thienyl)-2,3,4,9-tetrahydro-1H-β-carboline, a compound with potential GABA-receptor activity.
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Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 468–470, September–October, 2006. 相似文献
15.
G. Yu. Ishmuratov M. P. Yakovleva V. A. Ganieva R. Ya. Kharisov R. R. Gazetdinov A. M. Abulkaramova G. A. Tolstikov 《Chemistry of Natural Compounds》2006,42(1):92-95
Three new approaches to the synthesis of 1-bromo-3S-methylundecane, a key synthon in the synthesis of (S,S,S)-diprionylacetate, a sex pheromone of pine sawflies of the genera Diprion and Neodiprion, were proposed based on chemo-and stereoselective transformations of L-(-)-menthol derivatives.
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Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 73–76, January–February, 2006. 相似文献
16.
A new flavonoid, kaempferol-3,4′-di-O-α-L-rhamnopyranoside (1), and three known flavonoids (2–4) were isolated from the aerial parts of T. communis L. The structure of the new compound was elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed significant antioxidant activity (IC50 187.151 ± 0.821 μM, and 92.079±0.513 μM, respectively), whereas compounds 3 and 4 showed moderate activity in DPPH free radical scavenging assays.
Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 295–297, May–June, 2009. 相似文献
17.
The chemical composition of the essential oils of Achillea clavennae L., Achillea holosericea Sibth. & Sm., Achillea lingulata W. & K., and Achillea millefolium L. from the Balkans was determined by GC and GC/MS analyses. The main components were 1,8-cineole in A. holosericea, camphor in A. clavennae, β-pinene in A. millefolium, and τ-cadinol in A. lingulata. A detailed chemotaxonomic discussion is presented.
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Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 555–558, November–December, 2005. 相似文献
18.
A new xanthone (1, 1,7-dihydroxy-2-methoxyxanthone), in addition to the known metabolites 1,7-dihydroxyxanthone (2), 24(R)-stigmast-7,22 (E)-dien-3α-ol (3), and 1,7-dimethoxyxanthone (4), was isolated from the roots of Securidaca inappendiculata. Compounds 1–4 were evaluated by anti-HIV assay and 1–3 showed anti-HIV-1inhibitory activity in vitro.
Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 348–349, July–August, 2008. 相似文献
19.
The needle oils of Pinus sylvestris L. were analyzed by GC and GC-MS. The results showed some qualitative and quantitative variations. Forty-three components
were identified in the oils of P. sylvestris. All the samples of essential oils contained α-pinene, camphene, and β-pinene as major constituents. Chemical variations
of P. sylvestris samples were discussed.
Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 22–25, January–February, 2006. 相似文献
20.
A. L. Stroyuk A. E. Raevskaya A. V. Korzhak I. E. Kotenko E. M. Glebov V. F. Plyusnin S. Ya. Kuchmii 《Theoretical and Experimental Chemistry》2009,45(1):12-22
A relation was established between the composition of Cd
x
Zn1–x
S nanoparticles and their ability to accumulate excess negative charge during irradiation. The rate of expenditure of the
accumulated charge depends on the composition of the nanoparticles and is determined by their electric capacitance. A correlation
was found between the photocatalytic activity of the Cd
x
Zn1–x
S nanoparticles in the release of hydrogen from solutions of Na2SO3, their composition, and their capacity for photoinduced accumulation of excess charge. It was shown that Ni0 nanoparticles photodeposited on the surface of Cd
x
Zn1–x
S are effective cocatalysts for the release of hydrogen. It was found that ZnII additions in photocatalytic systems based on Cd
x
Zn1–x
S/Ni0 nanostructures have a promoting action on the release of hydrogen from water–ethanol mixtures.
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 45, No. 1, pp. 8–16, January-February, 2009. 相似文献