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PubMed1989

[Antitumor effects of 5-fluorouracil-bound organic silicon compound].

5-fluoro-3,4-dihydro-2,4-dioxo-N-[2-2- (dimethylphenylsilyl)ethylthioethyl]-1(2H)-pyrimidinocarb oxamide (SDK-12B-5), a novel antitumor agent, is covalently linked with 5-fluorouracil (5-FU) and 2-[(2-dimethylphenylsilyl)ethylthio] ethylamine(SDK-103) which possesses itself antitumor activity against murine solid tumors. It has a broad antitumor spectrum in experimental tumor systems including murine leukemias. Furthermore, SDK-12B-5 administered p.o. with various treatment schedules inhibited significantly the tumor growth of human breast cancer (MX-1), colon cancer (Co-4) and lung cancer (LX-1 and OAT) cells in BALB/c nu/nu mice and the chemotherapeutic index was about 10 for 4 different human cancer xenografts. In the Lewis lung carcinoma (LLC) metastasis model, SDK-12B-5 in combination with amputation of tumors inhibited significantly both the lymph node metastases and lung metastases of LLC and prolonged the life span (%ILS:91%) of BDF1 mice. We also found that the cell killing effect of SDK-12B-5 was affected by both concentration and exposure time in cultured human lung cancer (OAT) cells using soft-agar colony assay. A significant augmentation of delayed type hypersensitivity (DTH) response induced by SDK-12B-5 in comparison with the mixture of SDK-103 and 5-FU was seen when it was administered p.o. simultaneously with the immunization of sheep red blood cell (SRBC) in retired CD1 mice. From the studies on tissue distribution and pharmaco-kinetics of SDK-12B-5 by HPLC and ICP analysis. the persistence of SDK-12B-5 levels in serum and tumors was correlated with the findings that a maximum chemotherapeutic effect was obtained when SDK-12B-5 was administered p.o. repeatedly with every other day to avoid the cumulative toxicity.

Animals↗
PubMed1985

Kinetic determination of blood coagulation Factor XIII in plasma.

We have designed a new kinetic assay for estimating Factor XIII in plasma. Plasma fibrinogen is removed by treatment with bentonite (colloidal aluminum silicate) before measurement. During the lag phase, Factor XIII is transformed by thrombin and Ca2+ into active transglutaminase (EC 2.3.2.13), which attaches the substrate ethylamine to a glutamine residue in acetylated, dephosphorylated beta-casein. During the reaction, ammonia is released, which can be continuously monitored in an NADPH-dependent indicator reaction catalyzed by glutamate dehydrogenase (EC 1.4.1.4). We determined the optimal concentrations of substrate and activator and found that, to eliminate the clottable fibrinogen from the plasma samples, bentonite treatment was more advantageous than the traditional heat treatment. Results by the method correlate well with those by the most widely used amine incorporation and immunoinhibition assays for Factor XIII. We established a reference interval of 12.1-22.7 U/L; at optimal conditions, the variance of the method was less than 3% within this range. The method has several theoretical and practical advantages over traditional determinations of Factor XIII.

Ammonia↗
PubMed1987

Urinary metabolism of chlorphenoxamine in man.

After an oral dose of 40 mg of 4-chlorophenyl-methylbenzyloxy-N,N-dimethyl-ethylamine(chlorphe noxamine, Systral) urinary metabolism was studied by gas chromatography/mass spectrometry. Besides the unchanged drug, 8 metabolites and 7 artifacts and derivates could be identified. Metabolism is similar to that of the structurally related antihistaminic drugs diphenhydramine and doxylamine. The main metabolic pathways are: 1. N-demethylation, 2. oxidative desamination and formation of an alcohol and a carbonic acid derivative, 3. cleavage of the ether bond, and 4. hydroxylation of the phenyl ring. For determination of chlorphenoxamine in plasma an assay using gas chromatography was developed. Chlorphenoxamine plasma levels were beyond the limit of detection (10 ng/ml) 30, 60, 120, 240, 480, and 1200 min after oral intake.

Ethylamines↗
PubMed1988

Liquid-chromatographic assay of ibuprofen enantiomers in plasma.

This stereospecific "high-performance" liquid-chromatographic (HPLC) assay is suitable for pharmacokinetic studies of ibuprofen (IB). Very efficient extraction of the drug and internal standard, (+/-)-2-(4-benzoylphenyl)butyric acid, from plasma with isooctane/isopropanol (95/5, by vol) is followed by sequential reaction of the enantiomers with ethyl chloroformate and (S)-(-)-1-(1-naphthyl)ethylamine. The reactions take place at ambient temperature in less than 4 min. The naphthylethylamide derivatives of IB enantiomers and internal standard are then extracted into chloroform. After the organic layer is evaporated, the reconstituted residue is chromatographed at ambient temperature on a C18 reversed-phase column with a mobile phase of acetonitrile/water/acetic acid/triethylamine (55/45/0.1/0.02 by vol) at a flow rate of 1 mL/min. The IB diastereoisomers, detected at 232 nm, are free of interfering peaks and have a resolution factor of 2.2. Within the examined enantiomer concentration range of 0.1 to 20 mg/L in plasma, the peak-area ratios varied linearly with the corresponding IB concentrations. We used the assay to study the pharmacokinetics of IB enantiomers in plasma of a subject who took a single 600-mg dose of racemic drug.

Chromatography, High Pressure Liquid↗
PubMed1984

Characterization of the activity of growth factor from AH-130 tumor cells.

The activation of DNA synthesis induced by growth factor from the cytosol of AH-130 tumor cells (AH-130GF) was inhibited by alkylamines (methylamine, ethylamine, and dansylcadaverine), which inhibit the intracellular processing of hormone-receptor complexes. Calmodulin inhibitors (trifluoperazine and W-7) also inhibited the mitogenic action of AH-130GF, suggesting that the Ca-calmodulin system and proteolytic processing in lysosomes are necessary for stimulation of DNA synthesis by AH-130GF after its binding to the cell surface. Membrane phosphorylation induced by AH-130GF or epidermal growth factor (EGF) was investigated by using rat liver plasma membranes and 3T3 cell membranes in vitro. EGF increased the phosphorylation of two protein components with molecular weights of 160K and 130K in rat plasma membranes, but AH-130GF increased the phosphorylation of only the 130K protein. No specific phosphorylation induced by AH-130GF was detected in 3T3 cell membranes, but EGF induced phosphorylation of the 160K receptor protein.

Animals↗
PubMed1980

[On the problems in respect ot the formation of N-nitroso compound precursors when using alkylating agents in the fumigation of foodstuffs. I. Investigations of the formation of secondary amines by the action of ethylene oxide on primary amines and amino acids (author's transl)].

Special attention must be paid to the formation of secondary amines as precursors of nitrosamines as a possible consequence of the fumigation of foodstuffs with ethylene oxide. Investigations carried out in vitro show that secondary amines can result in various ways by reaction of the amine groups with ethylene oxide: 1. directly, by reaction of ethylene oxide with primary amines, 2. by reaction with amino acids followed by decarboxylation. Identification of the secondary amines produced by the reaction of ethylene oxide with primary amines or amino acids was carried out by means of thin layer chromatography. In this manner, the formation of methylamino ethanol, ethylamino ethanol and diethanolamine was demonstrated by the reaction of ethylene oxide with methylamine, ethylamine and ethanolamine. Furthermore, the reaction of ethylene oxide with glycine and serine followed by decarboxylation produced, depending upon the pH value, the compounds methylamino ethanol and diethanolamine.

Amines↗
PubMed1997

Naloxone-sensitive, haloperidol-sensitive, [3H](+)SKF-10047-binding protein partially purified from rat liver and rat brain membranes: an opioid/sigma receptor?

A naloxone-sensitive, haloperidol-sensitive, [3H](+)SKF-10047-binding protein was partially purified from rat liver and rat brain membranes in an affinity chromatography originally designed to purify sigma receptors. Detergent-solubilized extracts from membranes were adsorbed to Sephadex G-25 resin containing an affinity ligand for sigma receptors: N-(2- 3,4-dichlorophenyl]ethyl)-N-(6-aminohexyl)-(2-[1-pyrrolidinyl]) ethylamine (DAPE). After eluting the resin with haloperidol, a protein that bound [3H](+)SKF-10047 was detected in the eluates. However, the protein was not the sigma receptor. [3H](+)SKF-10047 binding to the protein was inhibited by the following compounds in the order of decreasing potency: (+)pentazocine > (-) pentazocine > (+/-)cyclazocine > (-)morphine > (-)naloxone > haloperidol > (+)SKF-10047 > DADLE > (-)SKF-10047. Further, the prototypic sigma receptor ligands, such as 1,3-di-o-tolylguanidine (DTG), (+)3-PPP, and progesterone, bound poorly to the protein. Tryptic digestion and heat treatment of the affinity-purified protein abolished radioligand binding. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE) of the partially-purified protein from the liver revealed a major diffuse band with a molecular mass of 31 kDa, a polypeptide of 65 kDa, and another polypeptide of > 97 kDa. This study demonstrates the existence of a novel protein in the rat liver and rat brain which binds opioids, benzomorphans, and haloperidol with namomolar affinity. The protein resembles the opioid/sigma receptor originally proposed by Martin et al. [(1976): J. Pharmacol. Exp. Ther., 197:517-532.]. A high degree of purification of this protein has been achieved in the present study.

Animals↗
PubMedDate not supplied

Direct enantioselective separation of clenbuterol by chiral HPLC in biological fluids.

An isocratic and simple high-performance liquid chromatographic method was developed for the direct resolution of the clenbuterol enantiomers. The method involved the use of a urea type chiral stationary phase (CSP) made of (S)-indoline-2-carboxylic acid and (R)-1-(alpha-napthyl) ethylamine known as the Chirex 3022 column. The stereochemical separation factor (alpha) obtained was 1.27 and the stereochemical resolution factor (Rs) was 4.2 when using a mobile phase composed of hexane:1,2-dichloroethane:ethanol/trifluoroacetic acid (80:10:10 by vol) at 23 degrees C. The (+)-R enantiomer eluted first, with a capacity factor (k'2) of 2.67 followed by (-)-S enantiomer with a capacity factor (k'1) of 3.38. As standard linear calibration curve was constructed over the range of 10 nmol/mL to 250 nmol/mL with a correlation coefficient of 0.999. The method is specific and sensitive with a lower limit of quantitation of 0.1 nmol. Data demonstrating recovery and precision of the assay are presented and the method has been used to monitor and identify quantitatively the profile of the enantiomers of clenbuterol in biological fluids.

Calibration↗
PubMed2000

Catalytic asymmetric hydroboration/amination and alkylamination with rhodium complexes of 1,1'-(2-diarylphosphino-1-naphthyl)isoquinoline

Catecholboronate esters formed by asymmetric hydroboration of arylalkenes are not directly converted to amines by reaction with hydroxylamine-O-sulfonic acid. Prior conversion to a trialkylborane by reaction with ZnEt2 or MeMgCl permits a subsequent amination reaction to occur with essentially complete retention of configuration, leading to a range of primary alpha-arylalkylamines in up to 97% enantiomeric excess (ee). Secondary, but not tertiary amines may be formed by a related pathway when in situ generated alkylchloramines are employed as the aminating agent. The catalytic asymmetric hydroboration, beta-alkylation and amination steps may be combined in a single stage. Overall, this provides a practical procedure for the synthesis of enantiomerically enriched arylamines, exemplified inter alia by the synthesis of (S)-1,2,3,4-tetrahydro-1-naphthylamine in 95-97% ee and of (R)-N-(cyclohexyl)-1'-(4-methoxyphenyl)ethylamine in 93% ee.

Journal Article↗
PubMed2000

Identification of the nitrogen-based blister agents bis(2-chloroethyl)methylamine (HN-2) and tris(2-chloroethyl)amine (HN-3) and their hydrolysis products on soil using ion trap secondary ion mass spectrometry.

The nitrogen blister agents HN-2 (bis(2-chloroethyl)methylamine) and HN-3 (tris(2-chloroethyl)amine) were directly analyzed on the surface of soil samples using ion trap secondary ion mass spectrometry (SIMS). In the presence of water, HN-1 (bis(2-choroethyl)ethylamine), HN-2 and HN-3 undergo hydrolysis to form N-ethyldiethanolamine, N-methyldiethanolamine and triethanolamine (TEA), respectively; these compounds can be readily detected as adsorbed species on soil particles. When soil samples spiked with HN-3 in alcohol were analyzed, 2-alkoxyethylamine derivatives were observed on the sample surfaces. This result shows that nitrogen blister agents will undergo condensation reactions with nucleophilic compounds and emphasizes the need for an analytical methodology capable of detecting a range of degradation and condensation products on environmental surfaces. The ability of ion trap SIMS to isolate and accumulate ions, and then perform tandem mass spectrometric analysis improves the detection of low-abundance surface contaminants and the selectivity of the technique. Utilizing these techniques, the limits of detection for HN-3 were studied as a function of surface coverage. It was found that HN-3 could be detected at a surface coverage of 0.01 monolayer, which corresponds to 20 ppm (mass/mass) for a soil having a surface area of 2.2 m(2) g(-1). TEA, the exhaustive hydrolysis product of HN-3, was detected at a surface coverage of 0.001 monolayer, which corresponds to 0.86 ppm.

3,4-Methylenedioxyamphetamine↗
PubMed2001

Circular dichroism of host-guest complexes of achiral pyridino- and phenazino-18-crown-6 ligands with the enantiomers of chiral aralkyl ammonium salts.

Circular dichroism (CD) spectroscopy was used for distinguishing different types of chiral interactions in host-guest complexes of achiral pyridino- and phenazino-18-crown-6 ligands with chiral aralkyl ammonium salts. The general feature of the CD spectra of many homochiral (e.g., (R,R)-host and (R)-guest) and heterochiral (e.g., (R,R)-host and (S)-guest) alpha-(1-naphthyl)ethylamine hydrogenperchlorate salt (NEA) complexes with chiral pyridino- and phenazino-18-crown-6 hosts is exciton interaction. The most interesting example is the coupling of the transitions of the chiral guest NEA with the energetically close transitions of the achiral phenazino-18-crown-6 host 6. The CD spectrum of the complex is predominated by exciton coupling between the (1)B(b) transition of the chiral guest and the (1)B(b) transition of the achiral host. The redshifted intense spectra of the complexes of (R)- or (S)-1-phenylethylamine hydrogenperchlorate salt (PEA) with the achiral diester-pyridino-18-crown-6 host 4 are indicative of merging the pi electron systems into one joint charge transfer chromophore. The appearance of weak bands with alternating sign in the spectrum of PEA complexes of the achiral "parent" pyridino-18-crown-6 host (1) indicates the presence of two or more conformers. The CD spectra of the complexes of achiral phenazino-18-crown-6 host 6 with PEA are also determined by pi-pi interaction. In addition to charge transfer bands, CD bands are also induced in the long-wavelength spectral region of the achiral host. The weak pi-pi interaction between the achiral phenazino-18-crown-6 host and methyl phenylglycinate hydrogenperchlorate (PGMA) or methyl phenylalaninate hydrogenperchlorate (PAMA) does not result in a definite spectral effect in the (1)L(a) region of the spectrum of the chiral guest, but its existence is proven by the weak CD bands induced in the long-wavelength spectral region of the achiral host.

Journal Article↗
PubMed1984

Morphologic and cytochemical characteristics of amine-containing globule leukocytes in rat tracheal epithelium.

Amine-containing cells in the tracheal epithelium are typically of the small-granule type (diameter approximately 100 nm). However, in the rat, another amine-containing cell type has been identified that possesses the amine-handling features of the APUD-series of cells (amine precursor uptake and decarboxylation) but not the ultrastructural characteristics. It has been postulated that these cells may be related to cutaneous melanocytes. In this study, fluorescent cells were present in the laryngeal and tracheal epithelial lining of adult Sprague-Dawley rats following freeze-drying and exposure to formaldehyde vapor (FIF or formaldehyde-induced fluorescence). Microspectrofluorimetry revealed an emission maximum at 493 nm. The excitation maximum could not be calculated but appeared to be around or below 350 nm (to record spectra below requires the use of quartz optics). Yellow fluorescence also emanated from serotonin-containing mast cells (excitation and emission maxima: 401/515 nm). Tracheal segments processed according to the aqueous formaldehyde ( AFIF ) technique, for the demonstration of 5- hydroxytryptophan (5-HTP) or serotonin (5-HT), failed to identify fluorescent cells in the epithelial lining even though connective-tissue mast cells were evident. Subsequent treatment of AFIF -fixed sections with formaldehyde and HCl vapors ( AFIF -HCl) resulted in the formation of a fluorogenic compound within numerous cells in the tracheal lining (455/537 nm). This spectral shift and increase in intensity of fluorescence following acidification are characteristic for standards and/or cells that contain tryptamine, tryptophan, or peptides with NH2-terminal tryptophan and are markedly different from microspectrofluorimetric data reported for the phenylethylamines or serotonin. It is therefore postulated that these cells contain a closely related beta-(3-indolyl) ethylamine-like compound, serotonin excluded. The morphology of the fluorescent cells was similar when prepared according to the FIF or AFIF -HCl techniques. Conjunctive staining, the examination of a single section first by fluorescence microscopy and subsequently by other histochemical and cytochemical methods, demonstrated that the fluorescent granules were also methylene blue, alcian blue, periodic-acid Schiff, and ferric- fericyanide positive. Subsequent correlative electron microscopic examination of Epon-embedded AFIF -HCl-treated tracheal sections demonstrated that these amine-containing cells were globule leukocytes.

Animals↗
PubMed1991

Pharmacological characterization of a 5-hydroxytryptamine-sensitive receptor/adenylate cyclase complex in the mandibular closer muscles of the cricket, Gryllus domestica.

The mandibular closer muscles of the cricket, Gryllus domestica, contain a 5-hydroxytryptamine (5-HT)-sensitive receptor that is coupled to adenylate cyclase. A structure-activity study of the 5-HT molecule indicates that the integrity of the ethylamine sidegroup and the presence of a negatively charged moiety at the 5 position (-OH, -OCH3) are essential for activity. A pharmacological profile is presented for this receptor. The receptor differs from any reported mammalian 5-HT receptor in that none of the mammalian agonists tested were effective. However, the mammalian antagonists for 5-HT receptors, spiperone, mianserin, and ketanserin as well as the anti-histaminic cyproheptadine were all effective antagonists in this preparation. Preliminary analysis of antagonism, particularly by spiperone, shows that these antagonists are probably acting non-competitively. On the basis of the pharmacological data, and comparisons with other insect systems, the 5-HT receptor present in the cricket mandibular muscles has been tentatively classified as 5-HT2-like.

Adenylyl Cyclases↗
PubMed1991

Synthesis and hypolipidemic activity of amine-carboxyboranes, and their amides and esters in rodents.

A series of amine carboxyboranes including their amides and esters were synthesized and shown to have potent hypolipidemic activity in rodents at 20 mg/kg/day. Ethylamine carboxyborane, di-n-propylamine-carboxyborane, trimethylamine-carbomethoxyborane, n-butylamine carbomethoxyborane, methylamine-N-ethyl carbamoylborane and trimethylamine-N-n-octyl carbamoylborane were the most potent derivatives demonstrating hypocholesterolemic and hypotriglycemic activities in rats orally at 20 mg/kg/day. These derivatives lowered tissue lipids, e.g. cholesterol, in the rat liver, small intestine and aorta. The fecal lipids were elevated. Furthermore, the agents lowered cholesterol and triglycerides in the serum VLDL and LDL fractions but caused elevations in the HDL fraction after 14 days. The agents inhibited hepatic enzymatic activities of rate limiting steps involved in lipid metabolism, e.g. ATP dependent citrate lyase, sn-glycerol-3-phosphate acyltransferase and phosphatidylate phosphohydrolase.

Amides↗
PubMed1992

Tricyclic azaergoline analogues: synthesis, structural modifications, and pharmacological studies.

As an extension of previous investigations on synthesis and dopamine autoreceptor activity of bicyclic ergoline analogues the tricyclic azaergoline analogues 9a and 9b were synthesized. Furthermore, the geometry of the aromatic beta-ethylamine moiety of 9a,b was modified by stereoselective construction of the cycloheptenyl fused pyrazolopyridine derivative 7 and the aminomethyl substituted tricycle 10. Binding affinity of these compounds at dopamine (DA) receptor sites was investigated employing rat striatum homogenate: The compounds reveal modest to weak, but selective binding to a dopamine D-2 receptor when it is labelled with the DA-autoreceptor agonist [3H]-SND 919. In vivo studies with mice showed that 7, 9a,b, and 10 affect their CNS activity.

Animals↗
PubMed1994

Selectivity of sterically fixed tryptamine and 5-methoxytryptamine derivatives for serotonin receptor subtypes, I: Synthesis of N-alkyl- and N,N-dialkyl-3-indolylbicyclo[2.2.1]heptane-2-amines.

Twenty-six title compounds with the ethylamine part of tryptamine or 5-methoxytryptamine fixed in an anticlinal ecliptic conformation were synthesized for assaying them at the different known serotonin receptors. Several alkylation methods have been improved and adapted for the space consuming norbornane system. The structures were fully elucidated by high-field NMR spectroscopy. All 1H- and 13C-signals could be assigned by means of 1H-1H- and 13C-1H-correlation spectroscopy (COSY).

Bridged Bicyclo Compounds↗
PubMed2004

Synthesis, structure, and cytostatic properties of new olivacine derivatives.

Starting from 2-(6-methoxy-1-methyl-9H-carbazol-2-yl)ethylamine and 6-methylpicolinic acid, 9-methoxy-5-methyl-1-(6-methylpyridin-2-yl)-6H-pyrido[4,3-b]carbazole 10 and its 6-alkylderivatives 12-17 were obtained. The newly obtained compounds showed significant cytostatic activity against cultured L1210 cells and high cytotoxicity towards various human tumor cell lines.

Animals↗
PubMed2005

Synthesis of 5,6-dimethyl-9-methoxy-1-phenyl-6H-pyrido[4,3-b]carbazole derivatives and their cytotoxic activity.

Starting from 2-(6-methoxy-1-methyl-9H-carbazol-2-yl)ethylamine 7 and mixed anhydrides of 4-nitrobenzoic acid or 4-methoxybenzoic acid, the corresponding 5,6-dimethyl-9-methoxy-1-(4-substituted phenyl)-6H-pyrido[4,3-b]carbazoles 11a-b, 5,6-dimethyl-9-hydroxy-1-(4-substituted phenyl)-6H-pyrido[4,3-b]carbazoles 12a, 12c, and their quaternary salts 13a-d were obtained. The four new pyridocarbazole derivatives 12a-c and 13d satisfy the international activity criterion for synthetic compounds, namely an ID(50) value lower then 4 microg/mL in preliminary in vitro cytotoxic activity screening against the A549 cell line (non-small cell lung cancer).

Antineoplastic Agents↗