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81.
A number of 8-aroyl-9-hydroxy-7,9,11-triaryl-3-oxo(or thioxo)-2,4-diazaspiro[5.5]undecane-1,5-diones 3a–g were synthesized from the reaction of 1,3-diaryl-2-propen-1-ones 2a–d with barbituric acid 1a and 2-thiobarbituric acid 1b in 50% aqueous ethanol under refluxing conditions without using any catalyst. The structures of the compounds were confirmed by ultraviolet, infrared, 1H and 13C NMR, mass, and elemental analysis.  相似文献   
82.
N-pivaloyl-Nˊ-(3,4-dichlorophenyl)thiourea (1): monoclinic, P21/a, a=11.57(1), b=9.278(8), c=13.51(1), β=103.85(1)°, V=1408(2)3 , Z=4, μ=0.598 mm-1 ; N-pivaloyl-N'-(3,5- dichlorophenyl)thiourea (2): monoclinic, P21/a, a=7.176(2), b=16.441(4), c=11.923(2), β=92.48(1)°, V=1405.3(6)3 , Z=4, μ=0.600 mm-1 ; N-pivaloyl-Nˊ-(2,6-dichlorophenyl)thiourea (3): orthorhombic, Pnma, a=26.79(1), b=8.780(4), c=5.955(3), V=1400.7(11)3 , Z=4, μ=0.601 mm-1 . All three complexes have an intramolecular hydrogen bond between NˊH and the carbonyl oxygen. Solution 1H NMR studies (CDCl3) show the NH resonance considerable downfield for each thiourea and their positions, as well as that of NH, is affected by substituents on the phenyl ring.  相似文献   
83.
The solvent extraction behavior of radioioine and astatine has been investigated under various conditions in order to compare the extraction behavior of astatine with radioiodine at tracer concentration. In this study, basic tracer solutions of astatine and radioiodine were extracted into the CS2 solution under various conditions. Astatine existed as a pure species in the tracer solution and formed cationic compound in the acidic solution which was also extracted into the organic solvent instantaneously. On the other hand, radioiodine existed as a complex in the tracer solution and was partly extracted into the organic solvent at tracer concentration. The observed different extraction behavior of astatine and radioiodine were consistently explained by the respective proposed extraction reaction schemes.  相似文献   
84.
The absolute configuration was determined for the title compound, C38H70NO13+·Cl?·3.5H2O. The cation contains a 14‐membered macrocyclic lactone and two sugars, namely cladinose and desos­amine. The six‐membered rings of the sugars adopt chair conformations. The structure is stabilized by strong hydrogen bonds, with O?O distances in the range 2.486 (9)–2.830 (5) Å; other distances are N?O = 2.860 (5), N?Cl = 3.134 (4) and O?Cl = 3.303 (4) Å.  相似文献   
85.
We report the synthesis of oligophenylene polycatenar liquid crystals incorporating 1,4-disubstituted phenyl rings joined by a direct carbon carbon bond and some pyrimidine analogues. The nature of the linkages does appear to affect the mesomorphism significantly. The ratio of the aromatic core to the aliphatic chains is varied systematically by changing the number of 1,4-disubstituted phenyl rings and the length of the aliphatic chains. This strongly influences the transition temperatures of the mesophases. Some of the compounds are columnar over an extended temperature range of more than 200°C with melting points below room temperature. We suggest that a combination of the poor overlap of the conjugated electron system of the molecular cores making up the columnar structure and the high concentration of aliphatic chains leads to a low charge-carrier mobility.  相似文献   
86.
Simple, sensitive, rapid, and accurate high-performance liquid chromatographic (HPLC) method is developed and validated for the simultaneous determination of diltiazem, metformin, pioglitazone, and rosiglitazone hydrochloride in raw materials, their pharmaceutical formulations, and human serum. In HPLC, all the above drugs were chromatographed using acetonitrile-methanol-water (30:20:50, v/v, pH 2.59 ± 0.02) as the mobile phase at a flow rate of 1.0 mL/min at ambient temperature. The separation is carried out on a Hiber, 250-4.6 RP-18 column, equipped with a UV-vis detector at 230 nm. All the antidiabetic drugs eluted at different retention time and each showed a good resolution from diltiazem. The method is successfully applied to pharmaceutical formulations because no chromatographic interferences from the tablet excipients are found. The method is found to be linear, accurate, and precise with apposite detection and quantification limit. Suitability of the method for the quantitative determination of the drugs is proven by validation in accordance with the requirements laid down by International Conference on Harmonization (ICH) guidelines. The validation results, together with statistical treatment of the data, demonstrated the reliability of this method.  相似文献   
87.
We have previously shown that conjugated ferrocenyl p-phenols show strong cytotoxic effects against both the hormone-dependent MCF-7 and hormone-independent MDA-MB-231 breast cancer cell lines, possibly via oxidative quinone methide formation. We now present a series of analogous amine and acetamide compounds: 2-ferrocenyl-1-(4-aminophenyl)-1-phenyl-but-1-ene (Z+E-2), 2-ferrocenyl-1-(4-N-acetylaminophenyl)-1-phenyl-but-1-ene (Z-3), and their corresponding organic molecules 1-(4-aminophenyl)-1,2-bis-phenyl-but-1-ene (Z+E-4) and 1-(4-N-acetamidophenyl)-1,2-bis-phenyl-but-1-ene (Z+E-5). All of the compounds have adequate relative binding affinity values for the estrogen receptor; between 2.8% and 5.7% for ERα, and between 0.18% and 15.5% for ERβ, as well as exothermic ligand binding in in silico ER docking experiments. Compounds 2 and 3 show dual estrogenic/cytotoxic activity on the MCF-7 cell line; they are proliferative at low concentrations (0.1 μM) and antiproliferative at high concentrations (10 μM). On the MDA-MB-231 cell line, the ferrocenyl complexes 2 and 3 are antiproliferative with IC50 values of 0.8 μM for 2 and 0.65 μM for 3, while the purely organic molecules 4 and 5 show no effect. Electrochemical experiments suggest that both 2 and 3 can be transformed to oxidized quinoid-type species, analogous to what had previously been observed for the ferrocene phenols.  相似文献   
88.
A novel and simple method is proposed for the determination of tetracycline by adsorptive voltammetry in a droplet using a carbon nanotube paste rotating disk electrode (CNTP-RDE). An enhanced electrochemical oxidation response of tetracycline was observed in pH 8.2 supporting electrolyte by the addition of a long-chain cationic surfactant, such as benzyldimethyltetradecylammonium chloride (zephiramine). Under the optimized experimental conditions, the calibration curve was linear across a tetracycline concentration range from 1.0?×?10?7 to 2.0?×?10?6 M. The limit of detection and sensitivity were 4.0?×?10?8 M and 0.9358?A M?1, respectively. This method was successfully employed for the determination of tetracycline in milk samples.  相似文献   
89.
We search for a non-SM-like CP-odd Higgs boson (a(1)(0)) decaying to tau(+)tau(-) or mu(+)mu(-) in radiative decays of the Upsilon(1S). No significant signal is found, and upper limits on the product branching ratios are set. Our tau(+)tau(-) results are almost 2 orders of magnitude more stringent than previous upper limits. Our data provide no evidence for a Higgs state with a mass of 214 MeV decaying to mu(+)mu(-), previously proposed as an explanation for 3 Sigma(+)-->pmu(+)mu(-) events observed by the HyperCP experiment. Our results constrain NMSSM models.  相似文献   
90.
Using a total of 2.74 x 10(7) decays of the psi(2S) collected with the CLEO-c detector, we present a study of chi(cJ)-->gammaV, where V=rho(0), omega, phi. The transitions chi(c1)-->gammarho(0 and chi(c1)-->gammaomega are observed with B(chi(c1)-->gammarho(0))=(2.43+/-0.19+/-0.22) x 10(-4) and B(chi(c1)-->gammaomega)=(8.3+/-1.5+/-1.2) x 10(-5). In the chi(c1)-->gammarho(0) transition, the final state meson is dominantly longitudinally polarized. Upper limits on the branching fractions of other chi(cJ) states to light vector mesons are presented.  相似文献   
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