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PubMed1975

Determination of bromazepam in plasma with an internal standard by gas-liquid chromatography.

A gaschromatographic assay method is described for the determination of Ro 5-3350 (bromazepam) using Ro 5-4547 (methylbromazepam) as internal standard. After alkaline ether extraction the bromazepam and methylbromazepam obtained from sulfuric acid reextraction are hydrolyzed to ABBP and to MABBP, respectively. After neutralization, the bromo-pyridine-benzophenones are extracted with ether and dissolved in hexane after evaporation of the ether. Under the described gaschromatographic conditions it was found that MABBP and ABBP have retention times of 10.5 and 12.5 min, respectively. The limit of sensitivity is situated at 5 ng/ml of plasma. The specificity is satisfactory since the metabolite which might have interfered (hydroxy-3-bromazepam) appears only at very low concentrations in the blood. The linearity of the calibration curve was confirmed for plasma concentrations up to 100 ng/ml.

Anti-Anxiety Agents↗

PubMed1989

Studies of ligand-induced conformational perturbations in myosin subfragment 1. An examination of the environment about the SH2 and SH1 thiols using a photoprobe.

The effect of ligand binding on the environment near the SH2 and SH1 thiols in myosin subfragment 1 has been investigated by photocross-linking after specific labeling of these thiols individually with 4-(N-maleimido)benzophenone (MBP). On photolysis, cross-linking occurred from SH2-MBP to the middle 50-kDa segment, and subsequent immunopeptide mapping revealed that the cross-link was made to a peptide stretch 31-32 kDa from the N terminus in the absence of MgADP, whereas in its presence the cross-link occurred at about 60-61 kDa from the N terminus. Photolysis of SH1-MBP in the absence of MgADP resulted in a major cross-link to the 27-kDa N-terminal segment and minor cross-links to the 50-kDa middle segment. In the presence of MgADP, no new cross-link occurred but the amount of cross-linking to the 50-kDa segment increased at the expense of the other. Immunopeptide mapping indicated that the regions in the 27- and 50-kDa peptides that were cross-linked to SH1-MBP are at about 14-16 and 55-56 kDa from the N terminus respectively. These results indicate that when nucleotide binds to S1, SH2 is displaced relative to the 50-kDa segment, whereas the local environment around SH1 does not change significantly because photolysis in the presence of MgADP resulted in a change at the site of cross-linking for SH2-MBP but caused only a redistribution of the relative amounts of the cross-links formed from SH1-MBP.

Animals↗

PubMed1989

N-trifluoroacetyl derivatives as pharmacological agents. IV--Antiinflammatory and related properties; antimicrobial activity of some polyaromatic trifluoroacetamides.

Taking into account both the analogy with the antiinflammatory triflamides and our previous observations on a series of trifluoroacetanilides active as acute and chronic antiinflammatory agents, the present series of polyaromatic N-trifluoroacetylderivatives were prepared. Their antiinflammatory and related properties as well as antimicrobial activity were evaluated. Few derivatives were found to display significant analgesic effects (hot plate test) whereas at 50 mg/kg all were devoid of antiinflammatory effects except the benzophenone derivative (III). Instead as regards the antimicrobial screening, a selective antimycoplasmal activity was revealed in six out of ten examined compounds.

Acetamides↗

PubMed1987

Psychopharmacological profile of the new cognition enhancing agent exifone in the mouse.

Hexahydro-2,3,4,3',4',5'-benzophenone (exifone, Adlone), a novel compound proposed for treating cognitive dysfunction in geriatric patients, was tested in a battery of standard psychopharmacological tests in the mouse. The results indicated that the compound was non-toxic and induced no signs of overt stimulation or sedation after acute administration of oral doses up to 1024 mg/kg. The compound was devoid of anxiolytic, anticonvulsant or classical neuroleptic activity and did not antagonize the effects of reserpine or a high dose of apomorphine, two tests indicative of classical antidepressant activity. On the other hand, exifone clearly decreased the duration of immobility in the tail suspension test and antagonized the hypothermia induced by a low dose of apomorphine. The compound shortened the duration of barbital induced sleep without affecting the duration of sleep induced by pentobarbital. The effects observed suggest that exifone is not devoid of psychotropic activity and might possess some properties of an atypical antidepressant.

Animals↗

PubMed1987

[Antifungal phytoiatric activity of various benzophenoximes].

Some derivatives of substituted benzophenone oximes were prepared and tested for phytoiatric antimycotic activity. The substances (I----XXI) (Table I) were subjected to in vitro and in vivo tests (in preventive phase). The compounds tested showed marked activity. The results proved the importance of the hydroximine function for the appearance of biological activity.

Animals↗

PubMed1986

[Mass-spectrometric analysis of 2-aminobenzophenone derivatives and their metabolites].

Mass-spectrometry analysis was carried out for 2-aminobenzophenone, its halogen derivatives and metabolites formed in the rat organism. The characteristic fragmentation patterns were outlined for the products arising on hydroxylation of the above compounds. The structural specificity in the oxidation of 2-aminobenzophenones was found to be different from that predominant in hydroxylation of phenyl (o-chlorophenyl) ring of 1,4-benzodiazepines which give on hydrolysis the respective benzophenones.

Animals↗

PubMed1981

Pharmacological and toxicological studies of a new non-steroidal anti-inflammatory drug: KC-8973.

A benzophenone derivative, 4-butyl-2'-fluorobenzophenone (KC-8973), having anti-inflammatory effects has been studied pharmacologically and toxicologically. On the carrageenin-induced paw edema, KC-8973 had the most potent activity of the tested commercial non-steroidal anti-inflammatory drugs. KC-8973 had a moderate effect on bradykinin-induced capillary permeability and lesser effect on dextran-, egg white- and serotonin-induced paw edemas in rats, respectively. From the detailed studies of prophylactic and therapeutic effects on the adjuvant-induced arthritis in rats, it was demonstrated that KC-8973 has an immuno-suppressive activity in addition to an anti-inflammatory effect. KC-8973 had a local-analgesic and antipyretic effect on the rat paw edema induced by brewer's yeast. KC-8973 caused no undesirable side effect at pharmacologically effective dose in the 1-month sub-acute toxicological study.

Animals↗

PubMed1998

Magnetic field effects on the behavior of radicals in protein and DNA environments.

We have examined the behavior of radical pairs derived by hydrogen abstraction of triplet benzophenone and some of its derivatives from bovine serum albumin, human serum albumin and calf thymus DNA. They have been investigated by means of nanosecond laser flash photolysis techniques. The dynamics of radical pair behavior are shown to be sensitive to external magnetic fields; these effects are interpreted using the established model for the influence of magnetic fields on radical pairs in micellar aggregates, in which intersystem crossing of the radical pair is slowed by the external magnetic field. Our results indicate that proteins and DNA can confine the radicals for a sufficiently long period of time for spin evolution to be affected by external fields. In proteins the radical pair retains its geminate character (i.e. remains confined) for about 0.5-1 microsecond. Interestingly, the magnetic field effects observed in proteins and in DNA seem to occur in distinct timescales; for example, for 2,3,4,5,6-pentafluorobenzophenone bound to DNA, the magnetic field alters the radical reactivity only over times < or = 50 ns, suggesting poor confinement. The timescale for these effects can be increased by promoting Coulombic attraction between DNA and the radical precursor. Electron transfer interactions play a role in the case of DNA.

Animals↗

PubMed1998

[Detection of lorazepam and lormetazepam metabolites in urine using thin-layer chromatography].

The determination of benzodiazepine derivatives lorazepam and lormetazepam in urine is based on detection of their metabolites 2-amino-2',5-dichlorobenzophenone and 2-methylamino-2'5-dichlorbenzophenone in hydrolyzed urine. Both substances are structurally very similar to the metabolites of diazepam 2-amino-5-chlorbenzophenone and 2-methylamino-5-chlorbenzophenone and their mobility on thin layer chromatograms is similar as well. This could cause their confusion and misinterpretation of the results. Therefore suitable combination of mobile phases and thin layer plates was sought in this study for the unambiguous identification of respective benzophenones by thin layer chromatography.

Anti-Anxiety Agents↗

PubMed1997

Significance of porosity and compliance of microporous, polyurethane-based microarterial vessel on neoarterial wall regeneration.

The microporous structure of artificial vascular grafts, which increases compliance and porosity simultaneously, may enhance neoarterial regeneration. In order to differentiate these effects, three models of segmented polyurethane grafts (inner diameter, 1.5 mm; wall thickness, 100 microns) with or without micropores fabricated using an excimer laser ablation technique, were prepared, and their neoarterial regenerative potentials were studied upon implantation: Model I (microporous, permeable, compliant); Model II (smooth-surfaced, impermeable, compliant); and Model III (smooth-surfaced, impermeable, noncompliant). In Models I and II, the pore or groove size (diameter, 100 microns) and pore or groove arrangement were fixed, and consequently their compliances were almost identical. Irrespective of model, the luminal surfaces were coated with benzophenone-derivatized gelatin and subsequently photocured. Twenty grafts (length, 20 mm) of each model were implanted in the aortas of rats. Predetermined implantation periods were 4, 12, and 24 weeks. Total patency rate decreased in the order Model I (100%), II (87%), and III (59%) grafts. All patent grafts were completely endothelialized after 12 weeks of implantation, irrespective of model. After 12- and 24-week implantations, in Model I grafts, the neoarterial wall was thin, and smooth muscle cells (SMCs) were of the contractile phenotype. In Model II grafts, the neoarterial wall exhibited considerable thickening. In Model III grafts, the neoarterial wall exhibited marked thickening, and SMCs were of the synthetic phenotype. The neoarterial wall thickness at the midportion of the grafts after 24 weeks of implantation increased in the order Model I (48 +/- 8 microns), II (146 +/- 87 microns), and III (385 +/- 21 microns) grafts. These results strongly suggest that compliance matching and porosity synergistically resulted in neoarterial wall restoration without appreciable thickening.

Animals↗

PubMed1999

Photocurable surgical tissue adhesive glues composed of photoreactive gelatin and poly(ethylene glycol) diacrylate.

This article presents a novel photochemically driven surgical tissue adhesive technology using photoreactive gelatins and a water-soluble difunctional macromer (poly(ethylene glycol) diacrylate: PEGDA).The gelatins were partially derivatized with photoreactive groups, such as ultraviolet light (UV)-reactive benzophenone and visible light-reactive xanthene dye (e.g., fluorescein sodium salt, eosin Y, and rose bengal). A series of the prepared photocurable tissue adhesive glues, consisting of the photoreactive gelatin, PEGDA, and a saline solution with or without ascorbic acid as a reducing agent, were viscous solutions under warming, and their effectiveness was evaluated as hemostasis- and anastomosis-aid in cardiovascular surgery. Regardless of the type of photoreactive groups, the irradiation of the photocurable tissue adhesive glues by UV or visible light within 1 min produced water-swollen gels, which had a high adhesive strength to wet collagen film. These were due to the synergistic action of photoreactive group-initiated photo-cross-linking and photograft polymerization. An increase in the irradiation time resulted in increased gel yield and reduced water swellability. A decrease in the molecular weight of PEGDA and an increase in concentration of both gelatin and PEGDA resulted in reduced water swellability and increased tensile and burst strengths of the resultant gels. In rats whose livers were injured with a trephine in laparotomy, the bleeding spots were coated with the photocurable adhesive glue and irradiated through an optical fiber. The coated solution was immediately converted to a swollen gel. The gel was tightly adhered to the liver tissue presumably by interpenetration, and concomitantly hemostasis was completed. The anastomosis treatment with the photocurable glue in the canine abdominal or thoracic aortas incised with a knife resulted in little bleeding under pulsatile flow after declamping. Histological examination showed that the glues photocured on rat liver surfaces were gradually degraded with time in vivo with infiltration of inflammatory cells and connective tissues without necrotic sign in surrounding tissue. In addition, in the laparoscopic surgery, percutaneous delivery of the glue and its in situ photogelation on rat liver surfaces were demonstrated using a specially designed fiberscope. These results indicate that the photocurable glues developed here may serve as a biodegradable tissue adhesive glue usable in cardiovascular surgery and endoscopic surgery.

Anastomosis, Surgical↗

PubMed2000

Adsorption of plasminogen from human plasma to lysine-containing surfaces.

The objective of this work is to develop blood-contacting surfaces that will dissolve nascent clots that may begin to form on them. Surfaces were prepared consisting of a polyurethane to which a coating reagent was attached covalently by photochemical methods. The coating reagent was a polyacrylamide with lysine and benzophenone (for photochemical attachment) moieties pendant to the chains. It was hypothesized that via the lysine moieties such surfaces would show specific binding affinity for plasminogen, the principal component of the fibrinolytic system in blood. Surfaces of varying lysine content in which the lysine was bound through the alpha-amino groups, leaving the epsilon-amino groups free, were investigated. A control surface in which the lysine was bound through the epsilon-amino groups was also examined. Advancing water contact angles showed the surfaces to be hydrophilic. Hydrophilicity was found to decrease as the lysine content increased. Adsorption of plasminogen from plasma was studied using radioiodinated plasminogen as a tracer. For the epsilon-lysine surfaces, adsorption increased with increasing lysine content and reached a value of 1.2 microg/cm(2) for the surface with the highest lysine content, that is, in the range expected for a compact monolayer of plasminogen. The control surfaces, which contained either no lysine or lysine in which the epsilon-amino groups were unavailable, adsorbed very small amounts of plasminogen. Immunoblots were obtained for the proteins eluted from the surfaces after incubation with plasma. For the control surfaces, most of the proteins tested for (some 20 in all) were present. However, for the surface containing the highest concentration of epsilon-lysine, only plasminogen was detected in a significant amount. It is concluded that the epsilon-lysine surface adsorbs plasminogen to the exclusion of the other plasma proteins. Studies to examine the fibrinolytic properties of these surfaces will constitute the next phase of this work.

Adsorption↗

PubMedDate not supplied

Some recent developments in the preparation of novel recognition systems: a recognition site for the selective catalysis of an aldol condensation using molecular imprinting and specific affinity motifs for alpha-chymotrypsin using a phage display peptide library.

Molecular imprinting and phage display library technologies are rapidly being accepted as useful techniques for the generation of ligand-selective recognition motifs. The use of molecular imprinting to produce a novel type II aldolase mimic selective for the cobalt(II)-mediated aldol condensation of benzophenone and acetaldehyde is reported here. Furthermore, peptide motifs have been identified which are acting as 'affinity ligands' selective for the recognition of the enzyme alpha-chymotrypsin using phage display techniques.

Acetaldehyde↗

PubMed2000

Integration of Layered Redox Proteins and Conductive Supports for Bioelectronic Applications.

Integration of redox enzymes with an electrode support and formation of an electrical contact between the biocatalysts and the electrode is the fundamental subject of bioelectronics and optobioelectronics. This review addresses the recent advances and the scientific progress in electrically contacted, layered enzyme electrodes, and discusses the future applications of the systems in various bioelectronic devices, for example, amperometric biosensors, sensoric arrays, logic gates, and optical memories. This review presents the methods for the immobilization of redox enzymes on electrodes and discusses the covalent linkage of proteins, the use of supramolecular affinity complexes, and the reconstitution of apo-redox enzymes for the nanoengineering of electrodes with protein monolayers of electrodes with protein monolayers and multilayers. Electrical contact in the layered enzyme electrode is achieved by the application of diffusional electron mediators, such as ferrocene derivatives, ferricyanide, quinones, and bipyridinium salts. Covalent tethering of electron relay units to layered enzyme electrodes, the cross-linking of affinity complexes formed between redox proteins and electrodes functionalized with relay-cofactor units, or surface reconstitution of apo-enzymes on relay-cofactor-functionalized electrodes yield bioelectrocatalytic electrodes. The application of the functionalized electrodes as biosensor devices is addressed and further application of electrically "wired" enzymes as catalytic interfaces in biofuel cells is discussed. The organization of sensor arrays, self-calibrated biosensors, or gated bioelectronic devices requires the microstructuring of biomaterials on solid supports in the form of ordered micro-patterns. For example, light-sensitive layers composed of azides, benzophenone, or diazine derivatives associated with solid supports can be irradiated through masks to enable the patterned covalent linkage of biomaterials to surfaces. Alternatively, patterning of biomaterials can be accomplished by noncovalent interactions (such as in affinity complexes between avidin and a photolabeled biotin, or between an antibody and a photoisomerizable antigen layer) to provide a means of organizing protein microstructures on surfaces. The organization of patterned hydrophilic/hydrophobic domains on surfaces, by using photolithography, stamping, or micromachining methods, allows the selective patterning of surfaces by hydrophobic, noncovalent interactions. Photoactivated layered enzyme electrodes act as light-switchable optobioelectronic systems for the amperometric transduction of recorded photonic information. These systems can act as optical memories, biomolecular amplifiers, or logic gates. The photoswitchable enzyme electrodes are generated by the tethering of photoisomerizable groups to the protein, the reconstitution of apo-enzymes with semisynthetic photoisomerizable cofactor units, or the coupling of photoisomerizable electron relay units.

Journal Article↗

PubMed2000

Bis axial ligation of simple imine and methyleneamido groups by ruthenium porphyrins

Bis(N-ethylideneethanamine)ruthenium(ii) porphyrins, [Ru11(Por)(N(Et)=CHMe)2] (Por=TTP, 4-Cl-TPP), were prepared by the reaction of dioxoruthenium(VI) porphyrins with triethylamine in approximately 85% yields. The reaction between dioxoruthenium(VI) porphyrins and benzophenone imine afforded bis(diphenylmethyleneamido)ruthenium(IV) porphyrins, [Ru(IV)(Por)(N=CPh2)2] (Por=TTP, 3,4,5-MeO-TPP), in approximately 65% yields. These new classes of metalloporphyrins were characterized by 1H NMR, UV/Vis, and IR spectroscopy as well as by mass spectrometry and elemental analysis. The X-ray crystallographic structures of [Ru(II)(TTP)(N(Et)=CHMe)2] and [Ru(IV)(3,4,5-MeO-TPP)(N=CPh2)2] revealed an axial Ru-N bond length of 2.115(6) A for the imine complex and 1.896(8) A for the methyleneamido complex. Each of the N=CPh2 axial groups in [Ru(IV)(3,4,5-MeO-TPP)(N=CPh2)2] adopts a linear coordination mode with a corresponding Ru-N-C angle of 175.9(9)degrees. Spectral and structural studies revealed essentially single bonding character for the bis(imine) complexes but a multiple bonding character for the bis(methyleneamido) complexes with respect to their axial Ru-N bonds.

Journal Article↗

PubMed2001

Diverse heteroleptic ytterbium(III) thiocyanate complexes by oxidation from bis(thiocyanato)ytterbium(II).

The new ytterbium(II) thiocyanate complex [Yb(NCS)2(thf)2] (1), synthesised by redox transmetallation between [Hg(SCN)2] and ytterbium metal in THF at room temperature, gave monomeric, eight coordinate [Yb-(NCS)2(dme)3] (2, dme = 1,2-dimethoxyethane) on crystallisation from DME, and is a powerful, synthetically useful reductant. Thus, oxidation of 1 with Hg(SCN)2, Hg(C6F5)2/HOdpp (HOdpp = 2,6-diphenylphenol), TlCp (Cp = C5H5 or CH3C5H4), Tl(Ph2pz) (Ph2pz = 3,5-diphenylpyrazolate) and CCl3CCl3 in THF yielded the ytterbium(II) complexes [Yb(NCS)3(thf)4] (3), [Yb-(NCS)2(Odpp)(thf)3](4), [Yb(NCS)2Cp-(thf)3] (Cp = C5H5 (5), CH3C5H4 (6)), [Yb(NCS)2(Ph2pz)(thf)4] (7) and [Yb(NCS)2Cl(thf)4] (8). In the solid state, complexes 4, 6 and 7 were shown by X-ray crystallography to be six, eight and eight coordinate monomers, respectively. Exclusively terminal, N-bound transoid thiocyanate bonding is observed with eta1-Odpp (4), eta5/-C5H4Me (6) and eta2-Ph2Pz (7) ligands attached approximately perpendicular to the N...N vector. The chloride complex 8 is not a molecular species, but consists of discrete, seven coordinate [YbCl2(thf)5] cations and [Yb(NCS)4(thf)3] anions. By contrast, oxidation of 1 with TlO2CPh gave a mixture of [[Yb(NCS)-(O2CPh)2(thf)2]2] (9) and 3 through rearrangement of an initially formed [Yb(NCS)2(O2CPh)] species. The X-ray structure of 9 indicates a dimeric complex with a (Yb(mu-O2CPh)4Yb] core that contains both bridging bidentate and bridging tridentate benzoate groups, and with a terminal N-bound thiocyanate and two THF ligands on each ytterbium. Reduction of Ph2CO with 1 in THF yielded the dinuclear complex [[Yb(NCS)2(thf)3]2(mu-OC(Ph)2C(Ph)2O)] (10), in which two octahedral Yb centres are bridged by a 1,1,2,2-tetraphenylethane-1,2-diolate ligand, derived from reductive coupling of the benzophenone reagent.

Journal Article↗

PubMed2004

Synthesis and NMDA-receptor affinity of ring and side chain homologous dexoxadrol derivatives.

The regioselectivity during transacetalization of benzophenone dimethyl acetal (4) with butane-1, 2, 4-triol (5) is controlled by the reaction conditions. Thermo-dynamic control leads predominantly to the 1, 3-dioxolane 6 whereas kinetic control favors the six-membered acetal 7. The amines 2a-e and 3a-e are synthesized from the alcohols 6 and 7 and are investigated in receptor binding studies with radioligands for their affinity to the phencyclidine binding site of the NMDA-receptor. In both series the primary amines 2a and 3a show the highest NMDA-receptor affinity (2a: Ki=3.38 microM; 3a: Ki=1.45 microM). The NMDA receptor slightly prefers the 1, 3-dioxane derivatives 3a and 3b compared to 2a and 2b (factor 2-3). Low interactions of the amines 3a and 3b with various receptor and reuptake systems indicate selectivity for the NMDA receptor. Surprisingly, the piperidine derivative 2e binds with high affinity at sigma1-receptors and, therefore, represents a novel lead compound for high affinity sigma1-receptor ligands.

Analgesics↗

PubMedDate not supplied

Mechanism for the interaction between triazolam and cimetidine.

Four normal volunteers each received three intraduodenal infusions of 0.5 mg triazolam solutions. Three treatments were: a pH 2.3 solution in which 47 per cent of the dose had hydrolysed to form a triazolo-benzophenone (TB); a pH 6.0 solution containing negligible TB; the pH 6.0 solution administered during cimetidine treatment (1200 mg day-1). TB was stable in serum and only very low TB serum concentrations were observed from the pH 2.3 treatment. No difference was observed in any triazolam pharmacokinetic parameter between the pH 6.0 and the pH 2.3 treatments. Cimetidine increased the triazolam AUC infinity and Cmax by 54 and 35 per cent, respectively. These results indicate that TB undergoes extensive presystemic conversion to triazolam and the triazolam-cimetidine interaction occurs primarily through a reduction in triazolam clearance.

Adult↗