Etude thermoanalytique de substances psychotherapeutiques. I. Anxiolytiques. Phenprobamate,meprobamate, clobazam et medazepam

The thermoanalytical study of phenprobamate (a), meprobamate I (b), clobazam (c), medazepam I (d) has enabled the existence of polymorphs for (d) to be established, and to confirm that of (b). The thermal stability and decomposition kinetics of commercial forms of drugs have been determined; their temperatures and intervals of fusion are given. Knowing the thermal behaviour of these compounds, their degree of purity: 99.67±0.19% (a), 99.32± 0.04% (b), 99.61±0.07% (c), 99.66±0.14% (d); their enthalpy, 27.58±0.69 (a), 34.23±1.22 (b), 30.38±0.81 (c), 21.48±0.75 kJ mole^-1; and entropy of fusion have been evaluated by differential scanning calorimetry.     

Etude thermoanalytique de substances psychotherapeutiques. II. Substances antipsychotiques. Chlorprothixene,chlorhydrate de chlorpromazine,chlorhydrate de levomepromazine,dichlorhydrate de fluphenazine

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.     

Simultaneous Radioimmunoassay of Plasma Testosterone and Dihydrotestosterone

Abstract

This report describes the simultaneous radioimmunoassay of plasma testosterone (T) and 5a-dihydrotestosterone (DHT), using as binding reagent a highly specific antiserum which reacted significantly with T and DHT. Utilizing a one step celite microcolumn to separate T from DHT, we have measured these two androgens accurately in small aliquots of plasma from both male and female subjects, Plasma concentrations of T and DHT expressed as mean ± S.D. in ng/ml were respectively: 1) in male subjects: a. normal adult: 4.9 ± 1.6 (T) and 1.3 ± 0.8 (DHT); b. hypogonadal: 0.24 ± 0.08 (T) and 0.20 ± 0.10 (DHT); c. prepubertal: 0.14 ± 0.02 (T) and 0.05 ± 0.02 (DHT). 2) in female subjects: a. normally menstruating, irrespective of time of cycle: 0.22 ± 0.07 (T) and 0.34 ± 0.17 (DHT); b. postmenopausal: 0.29 ± 0.08 (T) and 0.15 ± 0.07 (DHT); c. ovariectomized: 0.24 ± 0.06 (T) and 0.09 ± 0.01 (DHT). When plasma levels of T and DHT were measured during a complete menstrual cycle, the levels of these steroids were found to be higher during the luteal than during the follicular phose. The ratio of plasma T:DHT concentrations was five times higher in normal adult male (3.1) than in menstruating female subjects (0.6).     

Hair analysis of anabolic steroids in connection with doping control-results from horse samples

Doping control of anabolic substances is normally carried out with urine samples taken from athletes and horses. Investigation of alternative specimens, e.g. hair samples, is restricted to special cases, but can also be worthwhile, in addition to urine analysis. Moreover, hair material is preferred in cases of limited availability or complicated collection of urine samples, e.g. from horses. In this work, possible ways of interpretation of analytical results in hair samples are discussed and illustrated by practical experiences. The results demonstrate the applicability of hair analysis to detect anabolic steroids and also to obtain further information about previous abuse. Moreover, the process of incorporation of steroids into hairs is described and the consequences on interpretation are discussed, e.g. on the retrospective estimation of the application date. The chosen examples deal with the detection of the anabolic agent testosterone propionate. Hair samples of an application study, as well as a control sample taken from a racing horse, were referred to. Hair material was investigated by a screening procedure including testosterone, nandrolone and several esters (testosterone propionate, phenylpropionate, decanoate, undecanoate, cypionate; nandrolone decanoate, dodecanoate and phenylpropionate; limits of detection (LODs) between 0.1 and 5.0 pg/mg). Confirmation of testosterone propionate (LOD 0.1 pg/mg) was carried out by an optimised sample preparation. Trimethylsilyl (TMS) and tert-butyl dimethylsilyl derivatives were detected by gas chromatography-high-resolution mass spectrometry (GC-HRMS) and gas chromatography-tandem mass spectrometry (GC-MS/MS).     

Phytoecdysones ofSilene praemixta. I. Silenosterone

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.     

Ag2PbO2, Optimierung der Kristallzüchtung und Verfeinerung der Kristallstruktur

Ag₂PbO₂, Optimization of Crystal Growth and Crystal Structure Refinement Large single crystals of Ag₂PbO₂ (1×1×7 mm) suitable for measurements of anisotropic physical properties have been grown. The refinement of the crystal structure (I2/c; crystal size 0.08 × 0.08 × 0.31 mm; a = 6.0775(9), b = 8.704(1), c = 6.553(1) Å, β = 93.545(8)°; Z = 4; 1235 diffractometer data; R = 0.038) confirms the positions of the heavy atoms, and allows for an unambiguous determination of the oxygen coordinates.     

Measurement of 19-nortestosterone and its esters in equine plasma by high-performance liquid chromatography with tandem mass spectrometry

A high-performance liquid chromatographic-tandem mass spectrometric (HPLC/MS/MS) method for the determination of 19-nortestosterone and its esters (cyclopentanepropionate, phenylpropionate, and decanoate) in equine plasma is achieved using an atmospheric pressure chemical ionization (APCI) interface in selected reaction monitoring (SRM) mode. The two internal standards used were 16,16, 17-(2)H(3)-19-nortestosterone for 19-nortestosterone and methenolone acetate for its esters. The steroids studied were extracted from plasma samples with a mixture of diethyl ether/n-hexane (9:1, v/v). The quantification limits for 19-nortestosterone, 19-nortestosterone cyclopentanepropionate, 19-nortestosterone phenylpropionate, and 19-nortestosterone decanoate were 0.16, 5.0, 0.1, and 2.0 ng/mL, respectively, when 2 mL of plasma were used. The recoveries of most of the steroids were 71.6-101.0% except for the decanoate, which could be recovered to about 39.8%. The responses were linear, with correlation coefficients varying from 0.9897 to 0.9999 in the concentration range of 0.1 to 50.0 ng/mL for the steroids studied. When applied to equine (mare) plasma samples, the present method allowed detection of 19-nortestosterone up to 23 days after an intra-muscular injection of 400 mg as the decanoate.     

CuSeTeCl,CuSeTeBr und CuSeTeI: Verbindungen mit geordneten [SeTe]-Schrauben

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) ų (X = Cl), a = 8.155(3), b = 4.765(2), c = 11.286(4) Å, β = 104.21(3)°, V = 425.1(3) ų (X = Br) and a = 8.4370(9) b = 4.7652(5), c = 11.996(2) Å, β = 103.178(9)°, V = 469.6(1) ų (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.     

Determination of Δ4-3-ketosteroids based on oxime formation by difference circular dichroism spectroscopy

Δ⁴-3-Ketosteroids exhibit an intensive negative Cotton effect on the circular dichroism (CD) spectra in the wavelength range for the n-π* electronic transition (270–¶350 nm). With hydroxylamine hydrochloride, Δ⁴-3-ketosteroid compounds can be transformed into oxime derivatives. Following oxime formation, positive ellipticity with low intensity can be registered in this wavelength range. The quantitative determination of Δ⁴-3-ketosteroids is based on the considerable difference between the ellipticities before and after oxime formation. The difference ellipticity for the six ketosteroids examined (norethisterone, levonorgestrel, levonorgestrel acetate, methyltestosterone, testosterone phenylpropionate, nortestosterone phenylpropionate) varies linearly with the concentration in the interval 6 × 10^–6–3 × 10^–3 mol/L. The method can be well applied to determination of Δ⁴-3-ketosteroid contamination of norgestimate [(+)-13-ethyl-17-hydroxy-18,19-dinor-17α-pregn-4-en-20-yn-3-one oxime acetate]; 0.02–10% impurity can be measured.     

Zur Kristall- und MolekülStruktur des Hexaphenyldiplumbans

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, d_25°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.     

Synthesis,cytotoxic, and carbonic anhydrase inhibitory effects of new 2-(3-(4-methoxyphenyl)-5-(aryl)-4,5-dihydro-1H-pyrazol-1-yl)benzo[d]thiazole derivatives

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.     

Rate constants for the gas-phase reactions of Cl-atoms with C2?C8 alkanes at T = 296 ± 2 K

Relative rate constants for the gas-phase reactions of Cl-atom with thirteen atmospherically interesting alkanes (C₂? C₈) have been determined at 296 ± 2 K based on GC/FID measurements of their relative decays in the UV (λ ≥ 300 nm) photolysis of mixtures containing Cl₂ and the entire series of the selected alkanes in the mtorr range in 750 torr of N₂. The following absolute rate constants (in units of 10^?10 cm³ molecule^?1 s^?1) have been derived from the relative rate constants combined with the value of 1.94 × 10^?10 cm³ molecule^?1 s^?1 for the Cl + n-butane reaction: ethane (0.57 ± 0.05); propane (1.27 ± 0.02); 2-methyl propane (1.30 ± 0.01), 2-methyl butane ((1.96 ± 0.02)), n-pentane (2.50 ± 0.02); 2,3-dimethyl butane (2.00 ± 0.06); 2-methyl pentane (2.58 ± 0.08); n-hexane (3.05 ± 0.04); 2-methyl hexane (3.12 ± 0.04); n-heptane (3.65 ± 0.06); 2,2,4-trimethyl pentane (2.25 ± 0.08); and n-octane (4.09 ± 0.12). The uncertainties indicated are two least-squares standard deviations (2σ). These rate constants are compared with literature values and their applicability to Arctic tropospheric conditions is discussed. © 1995 John Wiley & Sons, Inc.     

Novel silver(I)N-heterocyclic carbene complexes bearing 2-(4-hydroxyphenyl)ethyl group: Synthesis,characterization, and enzyme inhibition properties

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 (K_i : 9.54 ± 0.98 μM and IC₅₀ : 17.40), and against α-Gly, 1c showed the highest effect (K_i 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 K_i values were measured as 5.45 ± 2.02 and 8.99 ± 2.02 μM, respectively.     

Spectrophotometric Determination of Steroid Oximes

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.     

Trans ligand influence in cobalt(III) Schiff base complexes: Electronic and steric effects on the kinetics of hydrolysis

Rate constants for the hydrolysis (k_h) of six different amines in trans‐[Co((BA)₂en)(amine)₂]ClO₄ complexes (amine = aniline 1a , para‐toluidine 1b , benzylamine 1c (primary amines), pyrrolidine 2a , piperidine 2b , morpholine 2c (secondary amines), and (BA)₂en = Bisbenzoylacetoneethylenediiminato) in mixed methanol/water (1:1) solvent have been determined between 30 and 55°C. The hydrolysis product of 2c , trans‐[Co((BA)₂en)(morpholine)(H₂O)]ClO₄, has been separately prepared and characterized by UV–vis and ¹H NMR spectroscopy. Depending on the nature of the axial amine ligand the limiting first‐order rate constants for the amine hydrolysis at 40°C range from (3.42 ± 0.10) × 10^?5 to (5.32 ± 0.13) × 10^?5 s^?1. At the first glance, a reasonable trend cannot be established between k_h and the basicity or the inductive trans effect of the amine ligands. However, when the complexes are classified into two groups, based on the type of the amine (primary and secondary), the values of k_h correlate well with the basicity or inductive effect of the amine in each group. The observed trend in k_h values for the complexes with primary amines is 1a (5.32 ± 0.13) × 10^?5 s^?1 > 1b (3.51 ± 0.14) × 10^?5 > 1c (1.72 ± 0.03) × 10^?5 (40°C), which is opposite to the amine basicity strength. In the case of the complexes with secondary amines, the observed trend in k_h values is in accord with amine basicity (or inductive trans effect), i.e. 2a (5.02 ± 0.22) × 10^?5 > 2b (4.18 ± 0.10) × 10^?5 > 2c (3.42 ± 0.10) × 10^?5 s^?1 (40°C). © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 387–393, 2002     

The crystals and molecular structure of 1,1,4,4-Tetraphenyl-2,5-di-(t-butyl)-1,4-diphosphoniacyclohexadiene-2,5-dichloride

The crystal and molecular structure of the title compound has been determined by single crystal, x-ray diffraction techniques. The compound crystallizes in a monoclinic space group of C2/c symmetry with four molecules in a unit cell of dimensions a = 24.578(1), b = 10.503(1), c = 17.579(1) Å and (3 = 1.30.93 ± .01°. The unit cell also contains two waters of crystallization which are involved in hydrogen bonds to the chloride ions. The central ring has been shown to be a diene which resides in a boat conformation defined by dihedral angles of 157°. The structure has been refined to a value of R = 0.08 using the 1535 statistically significant reflections measured out ot a 2θ value of 140°.     

Novel,racemic or nearly-racemic antibacterial bromo- and chloroquinols and γ-lactams of the verongiaquinol and the cavernicolin type from the marine sponge Aplysina (= Verongia) cavernicola

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.     

Thermodynamique de composes azotes. VII. Etude thermochimique du pyrazole et de l'imidazole

Enthalpies of sublimation for pyrazole and imidazole have been obtained by calorimetry at 298.15K. The ΔH⁰_sub (298.15 K) values for these two compounds are, respectively, 69.16 ± 0.32 and 74.50 ± 0.40 kJ mole^?1. From literature data obtained by combustion calorimetry for ΔH⁰_f (c, 298.15 K), the enthalpies of formation of these compounds in the gaseous state (pyrazole: 185.1 ± 2.3 kJ mole^?, imidazole: 133.0 ± 1.7 kJ mole^?1) have been derived. Several energy values related to the molecular structure of these two compounds (as resonance energy, enthalpy of isomerization, …) have been determined. The study of pyrazole has enabled us to contribute to the evaluation of some characteristics of the NN bond.     

Kinetics and mechanisms of the reactions of OH with some oxygenated compounds of importance in tropospheric chemistry

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.     

Dry state preparation of radioiodine labeled meta-iodobenzylguanidine

Radioiodination of meta-iodobenzylguanidine (MIBG) by the isotopic exchange technique in the dry state has been performed. Benzoic acid, pivalic acid and acetamide have been used as molten protic media to promote isotopic exchange reactions. Ammonium sulphate, diammonium hydrogen ortho-phosphate and ammonium chloride were used as catalysts which provide acidic media to facilitate exchange reactions. Maximum radiochemical yields of 97.1±1.3% and 84.3±1.6% [¹³¹I] MIBG were obtained when ammonium sulphate and benzoic acid were used. High radiochemical yields of 88.3±1.1% and 74.4±1.5% [¹³¹I] MIBG were also obtained in case of diammonium hydrogen orthophosphate and pivalic acid which suggests their successful use as reaction media in the radioiodination of MIBG. The activation energy for the exchange reaction in ammonium sulphate was calculated to be 10.8 kcal/mole.