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1.
The thermoanalytical study of chlorprothixene (a), chlorpromazine hydrochloride (b), levomepromazine hydrochloride (c), and fluphenazine hydrochloride (d), has enabled the existence of polymorphs for (b) and (d) to be shown. The thermal stability and decomposition kinetics of commercial forms of the drugs have been determined. The thermal behaviour of (c) and (d) does not permit their study by transparency method nor the determination of their degree of purity by differential scanning calorimetry. The temperatures and intervals of fusion are given for (a) and (b). Knowing the thermal behaviour, the degree of purity: 99.47 ± 0.11% (a), 99.61 ± 0.20% (b); enthalpy: 27.82 ± 1.05 (a), 28.42 ± 0.57 (b) kJ mole?1; and entropy of fusion have been evaluated by differential scanning calorimetry.  相似文献   

2.
The thermoanalytical study of testosterone (a), phenylpropionate (b), and decanoate (c) of testosterone has enabled the existence of polymorphs for (b) and (c) to be shown and to confirm that of (a). The thermal stability, decomposition kinetics of commercial forms of testosterone (I), phenylpropionate (I) and decanoate (II) of testosterone have been determined; their temperatures and intervals of fusion are given. Knowing the thermal behaviour of these drugs, their degree of purity: 99.69 ± 0.08% (a), 99.78 ± 0.07% (b), 99.53 ± 0.08% (c), their enthalpy 6151 ± 255 (a), 6123 ± 147 (b), 8598 ± 164 (c) cal mole?1, and entropy have been evaluated by differential scanning calorimetry.  相似文献   

3.
CuSeTeCl, CuSeTeBr, and CuSeTeI: Compounds with ordered [SeTe] Screws The hitherto unknown copper(I) chalcogen halides CuSeTeCl, CuSeTeBr and CuSeTeI have been prepared and their crystal structures were determined. The compounds of general composition CuSeTeX crystallize in the monoclinic system, space group P21/n (No. 14), Z = 4, a = 7.9796(9), b = 4.7645(8), c = 10.843(3) Å, β = 104.12(1)°, V = 399.8(1) Å3 (X = Cl), a = 8.155(3), b = 4.765(2), c = 11.286(4) Å, β = 104.21(3)°, V = 425.1(3) Å3 (X = Br) and a = 8.4370(9) b = 4.7652(5), c = 11.996(2) Å, β = 103.178(9)°, V = 469.6(1) Å3 (X = I). The crystal structures show infinite onedimensional screws YY′ of chalcogen atoms, with Y = Se and Y′ = Te alternately. The coordinations of Se and Te in these compounds are quite different.  相似文献   

4.
2-(3-[4-Methoxyphenyl]-5-aryl-4,5-dihydro-1H-pyrazol-1-yl)benzo[d]thiazoles ( 1b-7b ) were synthesized for the first time except 1b , and spectral methods such as 1H NMR, 13C NMR and HRMS were utilized to illuminate the chemical structures of the synthesized compounds. Phenyl ( 1b ), 2-methoxyphenyl ( 2b ), 4-methoxyphenyl ( 3b ), 4-methoxy-3-hydroxyphenyl ( 4b ), 2,5-dimethoxyphenyl ( 5b ), 3,4,5-trimethoxyphenyl ( 6b ), or thiophene-2-yl ( 7b ) was used as a aryl part. The inhibitory effects of the compounds were evaluated toward human carbonic anhydrase I and II enzymes (hCA I and hCA II). In vitro cytotoxic effects of the compounds against human oral squamous carcinomas and human normal oral cells were carried out via MTT. The compounds ( 1b-7b ) had Ki values of 36.87 ± 11.62-66.24 ± 2.99 μM (hCA I) and 22.66 ± 1.41-89.95 ± 6.25 μM (hCA II). Compounds 1b (Ki = 36.87 ± 11.62 μM) toward hCA I, 6b (Ki = 22.66 ± 1.41 μM) toward hCA II had significant enzyme inhibitory potency. Compound 6b had the highest tumor selectivity (TS = 29.3) and potency selectivity expression (PSE = 272.3) values. Therefore, compounds 1b and 6b with CAs inhibition effect and compound 6b with the cytotoxicity may be forwarded to further studies as potent compounds.  相似文献   

5.
The unit cell dimensions of hexaphenyldiplumbane (space group P21/c) have been newly determined: a = 17.16 ± 0.01, b = 9.410 ± 0.002, c = 21.60 ± 0.015 Å; β = 116.8 ± 0.2°; Z = 4; d (calc.) = 1.87, d25°C(obs.2)) = 1.88 g · cm?3. According to the evalution of 1800 independent reflections, and in contrary to a former investigation2), only molecules with an uniform Pb–Pb distance of 2.83 ± 0.01 Å exist in crystalline hexaphenyldiplumbane.  相似文献   

6.
Butanolic extracts of the Mediterranean sponge Aplysina (= Verongia) cavernicola have given, by reverse-phase HPLC, the antibacterial quinols (±)-3-bromoverongiaquinol (= (±)-3-bromo-1-hydroxy-4-oxo-2,5-cyclohexadine-1-acetamide; 1d) and (±)-3-bromo-5-chloroverongiaquinol (= (±)-3-bromo-5-chloro-1-hydroxy-4-oxo-2,5-cyclohexadine-1-acetamide; 1c ) besides the products of their formal cyclization 5-chlorohexadiene-1-acetamide; 1c ) besides the products of their formal cyclization 5-chlorocavernicolin (= 5-cloro-3,3a,7,7aβ-tetrahydro-3aβ-hydroxy-2,6(1H)-indoledione; 6) , the C(7)-epimerizing 7β-bromo-5-chlorocavernicolin (=7 β-bromo-5-chloro-3,3a,7,7aβ-tetrahydro-3aβ-hydroxy-2,6(1H)-indoledione; 4a and 7α-bromo-5-chlorocavernicolin (4b) , and the C(7)-epimerizing 5-bromo-7β-chlorocavernicolin ( = 5-bromo-7β-chloro-3,3a,7,7aβ-tetrahydro-3aβ-hydroxy-2,6(1H)-indoledione; 5a) and 5-bromo-7α-chlorocavernicolin (5b) . The latter four were isolated as mixtures of C(7)-epimerizing monoacetates 4a′/4b′ and 5a′/5b′. Both 1 and 1c proved to be racemic from NMR examination of their esterification products with (–)-methyl-oxyacetic acid, whilst 6 had a ca. 6% enantiomeric purity as shown by a 1H-NMR study of its monoacetate 6′ in the presence of a chiral shift reagent. These chiroptical data of the first chiral quinols from the Verongida and of 6 suggest phenol oxidative routes from tyrosine precursors for their formation. In view of their bioactivities, 1d and 1c have been synthesized from (p-hydroxyphenyl)acetic acid byt phenol oxidative routes.  相似文献   

7.
Five coiled-coil-containing proteins were synthesized to evaluate the influence of fusion sequences on their thermal stability. All proteins contained the same coiled-coil domain (VSSLESK)6, but differed in the fusion sequence attached. Circular dichroism spectroscopy was used to characterize their secondary structure and thermal stability. The proteins formed a coiled-coil structure, but their melting temperatures were different. The difference in the melting temperatures was not caused by either protein concentration or trace nickel ions. Sedimentation equilibrium experiments suggested an effect of the fusion sequence on the oligomerization state, but did not show a direct relationship between the oligomerization state and the melting temperature.

CD spectrum of the coiled-coil-containing proteins (10 × 10−6 M ) in 10 × 10−3 M PBS buffer at 25 °C.  相似文献   


8.
A simple and stereoselective total synthesis of (±)-maritimol ( 2d ) and its conversion into the other title compounds (±)-( 2a ), ((±)- 2b ), and ((±)- 2c ) is described. The unique bicyclo[3.2.1]octane moiety, constituting their C/D-ring system, is stereospecifically obtained by solvolytic rearrangement of the methanesulfonate 23 .  相似文献   

9.
《Analytical letters》2012,45(6):419-424
Abstract

A spectrophotometric procedure for the determination of steroid oximes is described utilizing 11β-hydroxy-iia-methyl-5β-pregnane -3, 20 -dione dioxime (I) and iia-hydroxy-progesterone dioxime (II) as models. The method is based on (a) acid hydrolysis to release hydroxylamine, (b) oxidation of hydroxylamine to nitrous acid with iodine, (c) diazotization of sulfanilic acid with the nitrous acid, (d) coupling of the diazonium compound with N-(i-naphthyl)-ethylenediamine dihydrochloride, and (e) measurement of the azo dye at 550 nm. A stoichiometric yield of hydroxylamine is obtained. Analyses of I and II have given typical recoveries (mean ± S. D.) of 99.5 ± 1.1% and 97.8 + 3.5%, respectively. The method is sensitive to ≥ 0.3 × 10?5 M dioxime.  相似文献   

10.
Studies on Polyhalides. 17. Preparation and Crystal Structure of Urotropinium Triiodide, UrHI3 Urotropinium triiodide C6H13N4I3 is formed by the reaction of equimolar amounts of urotropinium iodide and iodine in tBuOH as red-brown cube-like crystals melting at 402 K under decomposition. The compound crystallizes monoclinically in the space group P21/c with a = 952.0(3) pm, b = 1 160.2(6) pm, c = 1 149.9(4) pm, β = 92.22(3)° and Z = 4. The till now not described crystal structure (R = 0.027 for 1 860 observed reflexes) contains urotropinium ions UrH+ and slightly distorted triiodide ions I3?(d(I—I) = 292.3(1), 294.1(1) pm, φ(I—I—I) = 178.27(2)°) which are linked to ion pairs by a rather short contact (d(I …? I) = 389.0(1) pm, φ(I—I …? I) = 149.12(2)°).  相似文献   

11.
Herein, novel silver-based N-heterocyclic carbene (NHC) complexes bearing 2-(4-hydroxyphenyl)ethyl group were synthesized. Novel Ag(I)NHC complexes were synthesized from the 2-(4-hydroxyphenyl)ethyl-substituted benzimidazolium salts and silver oxide via in situ deprotonation method. The successful formation of all Ag(I)NHC complexes was proved by using 1H NMR, 13C NMR, FTIR spectroscopy, and elemental analysis techniques. In addition, their inhibitory effects have been investigated of these substances on acetylcholinesterase (AChE), α-glycosidase (α-Gly), human carbonic anhydrase I (hCA I), and human carbonic anhydrase II (hCA II) enzymes. It has been seen that all compounds have a better ability to inhibit compared with existing tried inhibitors. Among these, the best inhibitor against AChE enzyme is 1g (Ki : 9.54 ± 0.98 μM and IC50 : 17.40), and against α-Gly, 1c showed the highest effect (Ki 3.09 ± 0.36 μM and IC50 7.91). The best inhibitor against hCA I and hCA II enzymes are 1c and 1g compounds. For hCA I and hCA II, IC50 values were calculated as 17.85 and 9.06 μM and Ki values were measured as 5.45 ± 2.02 and 8.99 ± 2.02 μM, respectively.  相似文献   

12.
Reactions of 2,4,6-tri-t-butylphenoxyl (TBP) with cumene hydroperoxide (ROOH), cumylperoxyl radicals (RO2), and molecular oxygen in benzene solution have been investigated kinetically by the ESR method. The rate constant of the reaction TBP + ROOH has been estimated in the temperature range 27°-75°C: log10(k?7/M?1sec?1) = (7.1 ± 0.4) - (10.9 ± 0.6 kcal mole?1)/θ The ratio of the rate constants of reactions TBPH + RO2 products has been determined from the experimental dependence of the rate constant of reaction TBP with ROOH on [TBPH]0/[TBP]0. Putting k7 = 4.0 × 103M?1sec?1, we obtain k8 = (2.0 ± 0.2) × 108M?1sec?1 at 30°C. The reaction of TBP with O2 obeys the kinetic law ?d[TBP]/dt = k′[O2][TBP]2. This is in accordance with scheme TBP + O2 ← TBP ?O2 [I]; TBP ?O2 + TBP · products, log10 (k′/M?2sec?1) = (?14.5 ± 0.9) + (27.2 ± 1.4)/θ at 66°?78°C, where ° = 2.303RT.  相似文献   

13.
The haloacetyl ions [XCH2CO+], X = Cl, Br, I, have been produced by the dissociative ionization of selected precursor molecules and identified via their fragmentation characteristics. Their heats of formation, Δ, were 708 ± 8, 750 ± 25 and 784 ± 10 kJ mol?1, respectively, all appreciably above ΔH for [CH3CO+], 653 kJ mol?1. The effect of halogen substitution α to carbonyl is discussed for neutral molecules and their molecular ions.  相似文献   

14.
In addition to known ecdysteroids (2-deoxy-α-ecdysone and 2-deoxyecdysterone) fromSilene praemixta (Caryophyllaceae) we have isolated new ones — premixisterone and selenosterone (I), C27H42O7, mp 115–117°C (from MeOH), [α] D 28 +86.9 ± 2° (c 0.92, MeOH), yield 0.003%. The acetylation of (I) with (CH3CO)2O in Py gave 22-acetyl-selenosterone (II), C29H44O6, mp 210–212°C (MeOH-C6H14), [α] D 27 +45.5 ± 3° (c 0.16; MeOH). On the basis of physiocochemical and spectral characteristics it has been established that (I) has the structure of 14α,22R,25-trihydroxy-5β-cholest-7-ene-3,6-dione. The IR, PMR, and mass spectra of (I) and (II) are presented.  相似文献   

15.
A series of La(III) and Th(IV) complexes have been synthesized by template condensation of 2,6-diformyl-4-methylphenol, bis-(4-amino-5-mercapto-1,2,4-triazol-3-yl)alkanes and La(NO3)3 ·?6H2O/Th(NO3)4 ·?5H2O in 2 : 2 : 1 molar ratio in ethanol. These complexes were characterized by elemental analyses, magnetic susceptibility, molar conductance, spectral (IR, UV–Vis, 1H-NMR, FAB-mass), thermal, fluorescence and solid state d.c. electrical conductivity studies. The complexes are insoluble in water but soluble in DMF and DMSO. The observed molar conductance values indicate non electrolytes. Elemental analyses suggest 1 : 1 stoichiometry, [La(LI–IV)(NO3)(H2O)2] ·?3H2O and [Th(LI–IV)(NO3)2(H2O)2] ·?3H2O. Spectroscopic studies indicate that coordination occurs through phenolic oxygen after deprotonation, nitrogen of azomethine group and bridging bidentate nitrates. The solid state d.c. electrical conductivity indicates semiconducting nature. All the Schiff bases and their La(III) and Th(IV) complexes were evaluated for biological properties; some compounds show promising results.  相似文献   

16.
Reactions of OH(v = 1) with HBr, O, and CO have been studied at 295°K using a fast discharge flow apparatus: The reaction O + HBr → OH(v = 1) + Br was used as a source of OH(v = 1), and subsequent chemical reactions of the excited radical were followed using EPR spectroscopy. Rate constants for reactions (2b), (3b), and (6b) were measured as (4.5 ± 1.3) × 10?11, (10.5 ± 5.3) × 10?11, and <5 × 10?12 cm3/molec·sec, respectively. The rate constant for physical deactivation of OH(v = 1) by CO was determined as <4 × 10?13 cm3/molec·sec.  相似文献   

17.
A new strategy for the preparation of 8‐quinolyl ethers 3 ( a – g ), 5 ( a – g ), and 7 ( a – d ) was studied by copper (II)‐catalyzed methodology in the presence of Cs2CO3 and acetone–water mixture (1:1). Screening of quinolinyl‐8‐ethers was investigated against anticancer expressive studies to validate new chemical entity in medicinal chemistry. Approaches were evaluated against breast cancer (MCF‐7), skin cancer (G‐361), and colon cancer (HCT 116) cell lines. Inhibitory potentials against phosphoinositide‐3‐kinase (PI3K) enzyme responsible for cancer development have been evaluated by competitive ELISA studies. In PI3K assay, 3a – c were inactive (IC50 > 5 μM), while 3e – g , 5a , 5c – e , 5g , 7a , and 7d showed a moderate activity (IC50 ≥ 0.05 μM). Compounds ( 5b , 5f , 7b , and 7c ) showed significant activity (IC50 < 1.0 μM); thus, their anticancer activities were carried out. Anticancer activity was found to be selective towards breast cancer (MCF‐7); 5b , 5f , 7b , and 7c showed predominant relative percentage activities of 74.12%, 79.04%, 72.56%, and 78.47%, with IC50 values of 5b (2.27 ± 0.88 μM), 5f (1.38 ± 0.60 μM), 7b (2.64 ± 0.86 μM), and 7c (1.87 ± 0.68 μM) compared with the standard doxorubicin 73.14% inhibition (IC50 = 1.98 ± 0.75 μM). Docking study also conducted to find out the binding interactions with p110α (PDB ID: 3T8M) enzyme. Compounds 5b , 5f , 7b , and 7c showed best docking score into the active site of PI3K 12.59, 10.51, 56.52, and 8.61 nM. Structure–activity relationship studies demonstrated that the synthesized compounds are the potential PI3K inhibitors to treat various cancer‐related diseases.  相似文献   

18.
Rate constants for the gas phase reCedex 2, Franceactions of O(3P) atoms with a series of symmetric aliphatic ethers have been determined using the flash photolysis resonance fluorescence technique over the temperature range 240–400 K. The Arrhenius parameters derived from these data are (in units of cm3 molecule ?1 s?1): The error limits are two standard deviations derived from the least-squares fit. Rate constants for several other ethers were determined only at 298 K. The values obtained were (in units of 10?14 cm3 molecule?1 s?1): tetrahydrofuran (37.5 ± 1.1); 1,4?dioxane 1(6.81 ± 0.46); diethoxymethane (40.4 ± 1.8); ethyl -t-butyl ether (37.0 ± 1.3); and methyl-t-amylether (57.3 ± 2.3).  相似文献   

19.
Crystal Structures and Vibrational Spectra of Tetrahalogenoacetylacetonatoosmates(IV), [OsX4(acac)]?, X ? Cl, Br, I By reaction of the hexahalogenoosmates(IV) with acetylacetone the tetrahalogenoacetylacetonatoosmates(IV) [OsX4(acac)]? (X = Cl, Br, I) are formed, which have been purified by chromatography and precipitated from aqueous solution as tetraphenylphosphonium (Ph4P) or cesium salts. X-ray structure determinations on single crystals have been performed of (Ph4P)[OsCl4(acac)] ( 1 ) (triclinic, space group P1 , a = 9.9661(6), b = 11.208(2), c = 13.4943(7) Å, α = 101.130(9), β = 91.948(6), γ = 96.348(8)°, Z = 2), (Ph4P)[OsBr4(acac)] ( 2 ) (monoclinic, space group P21/n, a = 9.0251(8), b = 12.423(2), c = 27.834(2) Å, β = 94.259(7)°, Z = 4) and (Ph4P)[OsI4(acac)] ( 3 ) (monoclinic, space group P21/c, a = 18.294(3), b = 10.664(2), c = 18.333(3) Å, β = 117.68(2)°, Z = 4). Due to the increasing trans influence in the series O < Cl < Br < I the Os? O. distances of O.? Cl? X′ axes are lengthened and the OsO. stretching vibrations are shifted to lower frequencies. The Os? X′ bond lenghts are shorter as compared with symmetrically coordinated X? Os? X axes.  相似文献   

20.
The kinetics of the reactions have been studied in a discharge flow system under pseudo-first-order conditions. The OH concentration was monitored by laser induced fluorescence and helium was used as the carrier gas. Values of k1 = (8.1 ± 1.7) × 10?13, k2 = (1.31 ± 0.26) × 10?11, k3 = (2.6 ± 0.5) × 10?11, and k4 = (2.5 ± 0.4) × 10?11 cm3 molecule?1 s?1, at 298 K and 1 torr total pressure, were obtained. To validate the newly constructed system the rate constant for the reaction was determined in a similar manner. The value of k5 = (6.7 ± 0.9) × 10?12 cm3 molecule?1 s?1 at 298 K and 1 torr total pressure is in very good agreement with other literature values. The mechanisms for the atmospheric degradation of these compounds have been constructed to allow their incorporation in a photochemical trajectory computer model, to assess their impact on photochemical ozone creation in the troposphere. © 1994 John Wiley & Sons, Inc.  相似文献   

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