scispace - formally typeset
Search or ask a question

Showing papers in "Archiv Der Pharmazie in 1980"


Journal ArticleDOI
TL;DR: In this paper, the authors studied the effect of O 2−•-scavenging properties on the cyclooxygenase reaction during prostaglandin formation in the renal medulla of the rat.
Abstract: Eine Hemmung der Cyclooxygenase-Reaktion bei der Prostaglandinbildung des Rattennierenmarks in vitro ist durch verschiedene Flavonoide mit o-Dihydroxystrukturen moglich. Diese Flavonoide mit einer Brenzcatechin-Anordnung im Molekul besitzen ausgepragte Radikalfangereigenschaften fur Peroxid-Anion-Radikale. Dagegen konnen einige Flavonoide und Phenolderivate, die starke O2−•-Radikalfanger sind, die Prostaglandinsynthetase aber auch aktivieren oder unbeeinflust lassen. Eine Korrelation zwischen den Radikalfangereigenschaften und der Beeinflussung des Cyclooxygenase-Enzyms besteht folglich bei den untersuchten Verbindungen nicht. Prostaglandin Synthetase Inhibition by Flavonoids and Phenolic Compounds in Relation to their O2−•-Scavenging Properties Several flavonoids containing an o-dihydroxy function inhibit the cyclo-oxygenase reaction during prostaglandin formation in the renal medulla of the rat. These flavonoids are strong scavengers for peroxide anion radicals. On the other hand, some flavonoids and phenolic compounds with strong O2−•-scavenging properties either stimulate the prostaglandin synthetase or have no effects. Thus, the radical scavenging properties of the compounds studied do not correlate with their influences on the cyclo-oxygenase activity.

115 citations


Journal ArticleDOI
TL;DR: In this article, 27 derivatives of 4-hydroxy-2H-pyran-2-one were synthesized and tested for their anticoagulant and blood platelet aggregation inhibiting activity.
Abstract: Die Synthese und die gerinnungsphysiologische Prufung von 27 Derivaten des 4-Hydroxy-2-pyranons wird beschrieben. Nach einmaliger oraler Verabreichung von 330 mg/kg an Ratten wurden bei 14 Substanzen Prothrombinspiegel von weniger als 25 % gefunden. Diese Werte werden bereits nach 12 h erreicht und bis zu 48 h nach Applikation aufrecht erhalten. Das Wirkungsmaximum liegt meist zwischen 24 und 36 h. Mit der aktivsten Verbindung 11 werden therapeutische Prothrombinspiegel noch nach einmaliger Gabe von 100 mg/kg erreicht. Der Vergleich des 4-Hydroxy-2-pyranons 1 mit dem entsprechenden 4-Hydroxycumarinderivat 28 zeigt, das die Aktivitaten in der gleichen Grosenordnung liegen. Vier Substanzen waren in Konzentrationen von 5 · 10−4 M schwache Thrombozytenaggregationshemmer. Anticoagulant 4-Hydroxy-2-pyrones Twenty-seven derivatives of 4-hydroxy-2H-pyran-2-one were synthesized and tested for their anticoagulant and blood platelet aggregation inhibiting activity. After oral administration of a single dose of 330 mg/kg to rats, prothrombin levels below 25 % were seen with 14 compounds. These values were reached after almost 12 h and maintained up to 48 h. Maximum activity is observed between 24 and 36 h. The most active compound 11 shows therapeutic prothrombin levels even after administration of 100 mg/kg. The 4-hydroxy-2-pyranone 1 and the corresponding 4-hydroxycumarine 28 show similar activity. Four compounds were weak platelet aggregation inhibitors (5 · 10−4 M).

27 citations




Journal ArticleDOI
TL;DR: Sydnone derivatives with various substituents at C‐4 of the phenyl ring and at C-2 of the thiazolyl ring were synthesised and tested for antiinflammatory activity and five compounds have shown promising results.
Abstract: Sydnone derivatives with various substituents at C-4 of the phenyl ring and at C-2 of the thiazolyl ring were synthesised and tested for antiinflammatory activity. Five compounds have shown promising results. Synthese und entzundungshemmende Wirkung 3-substituierter 4-(4′-Thiazolyl)-Sydnone Sydnonderivate mit verschiedenen Substituenten in 4-Position des Phenyl- und 2-Position des Thiazolylringes wurden synthetisiert und auf entzundungshemmende Wirkung getestet. Funf der untersuchten Verbindungen zeigen vielversprechende Ergebnisse.

23 citations



Journal ArticleDOI
TL;DR: In this article, a mechanism for 2-bromo-1,4-naphthoquinone reaction with ethylenediamine (2e) with 3 realisiert.
Abstract: 1,4-Naphthochinone 2 reagieren mit Ethylendiamin (3) zu 5-substituierten 2,3,4-Trihydro-benzo[f]-chinoxalin-6-onen 7. Die analogen Reaktionen mit N-Acetyl-ethylendiamin (12) zeigen, das die Amino-1,4-naphthochinone 6 und nicht die 1,4-Naphthochinon-imine 4 Zwischenstufen sind. Die Verbindungen 6 entstehen nach einem Additions-Enolisierungs-Oxidations- oder Additions-Eliminierungs-Mechanismus. Beide Mechanismen werden bei der Umsetzung des 2-Brom-1,4-naphthochinons (2e) mit 3 realisiert. Quinone Amine Reactions, IV: 2,3,4-Trihydrobenzo[f]quinoxalin-6-ones 1,4-Naphthoquinones 2 react with ethylenediamine (3) to yield 5-substituted 2,3,4-trihydrobenzo[f]-quinoxalin-6-ones 7. The analogous reactions with N-acetylethylenediamine (12) indicate that amino-1,4-naphthoquinones 6 are intermediates but not 1,4-naphthoquinoneimines 4. Compounds 6 result from addition-enolization-oxidation or addition-elimination mechanism. Both mechanisms are found to occur in the reaction of 2-bromo-1,4-naphthoquinone (2e) with 3.

22 citations


Journal ArticleDOI
TL;DR: In this article, the synthesis of enantiomeric α, Nα-Dimethylhistamines (+−3 and (−−3) was reported, and the determination of the absolute configuration and histamine-like activity of the enantiomers on the guinea-pig ileum (H1) and atrium (H2) were reported.
Abstract: Es werden die Synthesen der enantiomeren α, Nα-Dimethylhistamine (+)—3 und (−)—3, die Ableitung der absoluten Konfiguration sowie die histaminartige Wirksamkeit der Enantiomere am Ileum (H1) und Atrium (H2) des Meerschweinchens beschrieben. Structure-Activity Relationship of Histamine Analogues. XXII: Absolute Configuration and Histamine-like Activity of the Enantiomeric α, Nα-Dimethylhistamines The synthesis of the enantiomeric α, Nα-Dimethylhistamines (+)—3 and (−)—3, the determination of the absolute configuration and the histamine-like activity of the enantiomers on the guinea-pig ileum (H1) and atrium (H2) are reported.

22 citations


Journal ArticleDOI
TL;DR: Aloin was separated into aloin A and aloin B by HPLC as discussed by the authors, and the two aloins differ mostly in optical rotation and circular dichroism, and they were separated into two classes of diastereomers: 1H-NMR and 10 S, 1′-R-compound.
Abstract: Aloin wurde durch Hochdruckflussigkeitschromatographie in Aloin A und Aloin B getrennt. Aloin A last sich aus Aloin auch durch mehrfache Kristallisation aus Methanol rein gewinnen. Die Aloine unterscheiden sich insbesondere durch ihre optischen Drehwerte und circulardichroitischen Effekte. Wie die Partialsynthese aus Anthronen und α-Bromacetoglucose zeigte, ist in beiden Aloinen der Glucosylrest β-standig mit dem Aloeemodinanthron verbunden; C-1′ des Glucosylrestes ist R-konfiguriert. Aloin A und B unterscheiden sich durch die Konfiguration von C-10 des Anthronrestes. Die Auswertung der 1H-NMR-Spektren macht fur Aloin A die 10 R, 1′R-Konfiguration wahrscheinlich, fur das chemisch labilere Aloin B die 10 S,1′R-Konfiguration. Resolution of Aloin into Diastereomers and Their Characterization Aloin was separated into aloin A and aloin B by HPLC. Aloin A may also be obtained by crystallization of aloin from methanol. The two aloins differ mostly in optical rotation and circular dichroism. The synthesis from anthrones and acetobromoglucose shows that in both aloins the anthrone is in the β-position of the D-glucose. C-1′ of the D-glucose has the R-configuration. Aloin A and aloin B have different configurations at C-10 of the anthrone part. 1H-NMR spectra show that aloin A is the 10 R,1′R- compound, whereas the chemically less stable aloin B is the 10S, 1′-R-compound.

22 citations


Journal ArticleDOI
TL;DR: In this article, the 3-pyrazolo-1,2,4-triazino-5,6-b'indole and its derivatives are prepared by the cyclisation of isatin 3-thiosemicarbazone (1) followed by condensation and displacement reactions.
Abstract: 1,2,4-Triazino[5,6-b]indoles and their derivatives are prepared by the cyclisation of isatin 3-thiosemicarbazone (1) followed by condensation and displacement reactions. Condensations of 3-hydrazino-1,2,4-triazino[5,6-b]indole (4) with ethoxymethylenemalononitrile, ethyl ethoxymethylenecyanoacetate, acetylacetone and methyl bis(methylmercapto)methylenecyanoacetate yield the corresponding 3-pyrazolo-1,2,4-triazino[5,6-b]indoles 6–9. The hydrazine 4 is further transformed into the higher heterocycles 10–12 on reaction with formic, acetic or nitrous acids. Uber kondensierte Triazine als chemotherapeutische Wirkstoffe, 2. Mitt.: Synthese von 1,2,4-Triazino‘5,6-b’indol und verwandten Verbindungen 1,2,4-Triazino‘5,6-b’indole und ihre Derivate werden durch Cyclisierung von Isatin-3-thiosemicarbazon (1)gefolgt von Kondensations-und Umlagerungsreaktionen hergestellt. Die Kondensation von 3-Hydrazino 1,2,4-triazino‘5,6-b’indol (4) mit Ethoxymethylenmalononitril, Ethoxymethylencyanessigsaureethylester, Acetylaceton und Bis(methylmercapto)-methylencyanessigsauremethylester ergibt die entsprechenden 3-Pyrazolo-1,2,4-triazino‘5,6-b’indole 6–9. Durch Umsetzung mit Ameisensaure, Essigsaure oder salpetriger Saure kann das Hydrazin 4 in die hoheren Heterocyclen 10–12 umgewandelt werden.

19 citations



Journal ArticleDOI
TL;DR: In this paper, the 1,3-dicarbonyl compounds have been shown to possess antiallergic activity and antiallergisch wirksamen Sauren 8, die sich zu den Pyrono[3,2-b]indolen 9 decarboxylieren lassen.
Abstract: N-Alkyl-anthranilsauren reagieren mit Chloraceton/K2CO3 unter Bildung von 1-Alkyl-2-acetyl-3-hydroxy-indolen 3. Die 1,3-Dicarbonylverbindungen 3 kondensieren mit Oxalsaurediestern zu den 1,3,5,6-Tetracarbonylverbindungen 5, die beim Erhitzen in mit HCl-gesattigten Alkoholen zu den 4-Pyron-2-carbonsaureestern 6 cyclisieren. Aus 6 erhalt man die antiallergisch wirksamen Sauren 8, die sich zu den Pyrono[3,2-b]indolen 9 decarboxylieren lassen. Kondensation von 5 mit Orthoameisensaureestern/Acetanhydrid ergibt die 4-Pyron-3-ketocarbonsaureester 7, 6 und 9 werden in die Thiocarbonylverbindungen 11 und 12 uberfuhrt. Aus 6c und Ammoniak erhalt man das Saureamid 10. 1,3-Dicarbonyl Compounds, XV: 4,5-Dihydro-5-alkyl-4-oxopyrano[3,2-b]indoles N-Alkylanthranilic acids react with chloroacetone/K2CO3 to form the 1-alkyl-2-acetyl-3-hydroxy-indoles 3. The 1,3-dicarbonyl compounds 3 condense with dialkyl oxalates to yield the 1,3,5,6-tetra-carbonyl compounds 5, which cyclize on heating with alcohols, saturated with HCl, to form the alkyl 4-pyrone-2-carboxylates 6. The acids 8, obtained from 6, possess antiallergic activity. Decarboxylation of 8 affords the pyrono[3,2-b]indoles 9. Condensation of 5 with triethyl orthoformate/acetic anhydride yield the alkyl 4-pyrone-3-ketocarboxylates 7. Compounds 6 and 9 are converted to the thiocarbonyl compounds 11 and 12. The amide 10 is obtained from 6c by reaction with ammonia.


Journal ArticleDOI
TL;DR: Ausgehend von den chiralen disubstituierten Cyanessigsauren 1 werden uber die Isocyanate 3 die Racemate and einige Enantiomere der 5,5disubstituerten Hydantoine 6 and der 3-Methylhydantoine 7 synthetisiert.
Abstract: Ausgehend von den chiralen disubstituierten Cyanessigsauren 1 werden uber die Isocyanate 3 die Racemate und einige Enantiomere der 5,5-disubstituierten Hydantoine 6 und der 3-Methylhydantoine 7 synthetisiert. Ihre absolute Konfiguration wird abgeleitet.

Journal ArticleDOI
TL;DR: The trans-3,3′-dihydroxy-α,β-dialkylstilbenes 1, 3-5 are antiestrogens with a marked effect on the DMBA-induced hormone dependent mammary carcinoma of the SD-rat as discussed by the authors.
Abstract: Die trans-3,3′-Dihydroxy-α,β-dialkylstilbene 1,3–5, Antiostrogene mit einer ausgepragten Wirkung am DMBA-induzierten hormonabhangigen Mammaadenocarcinom der SD-Ratte (speziell 3 und 4), sind durch Umsetzung von 3-Methoxyphenyldiazoalkanen c mit SO2 zu 1,1-Dioxo-2,5-dialkyl-2,5-di-(3′-methoxyphenyl)-Δ3-1,3,4-thiadiazolinen d, thermische Zersetzung von d zu 3,3′-Dimethoxy-α,β-dialkylstilbenen e und Etherspaltung von e erhaltlich. Mammary Tumor Inhibiting Antiestrogens of the 3,3′-Dihydroxy-α,β-dialkylstilbene Type. The trans-3,3′-dihydroxy-α,β-dialkylstilbenes 1, 3–5 are antiestrogens with a marked effect on the DMBA-induced hormone dependent mammary carcinoma of the SD-rat (especially 3 and 4). They are synthesized by reaction of (3-methoxyphenyl)diazoalkanes c with SO2 to give 1,1-dioxo-2,5-dialkyl-2,5-bis-(3-methoxyphenyl)-Δ3-1,3,4-thiadiazolines d. Thermal decomposition yields the 3,3′-dimethoxy-α,β-dialkylstilbenes e which are then subjected to ether cleavage.

Journal ArticleDOI
TL;DR: In this paper, the synthesis and pharmacological properties of the title compounds are described, together with their properties and properties in terms of synthesis, synthesis, and pharmacology properties, respectively.
Abstract: Synthese und Pharmakologie der Titelverbindungen 13, 15, 16 und 17 werden beschrieben. Thiophene as a Structural Element of Physiologically Active Compounds, IV: o-Substituted 5-Phenylthieno[2,3-e][1,4]diazepines. Synthesis and pharmacological properties of the title compounds 13, 15, 16, and 17 are described.

Journal ArticleDOI
TL;DR: In this paper, a new anti-plasmodic structure for the title compound was proposed, where neither the quinoline ring nor the sulfonamide group nor type and place of the attachement between them can be changed without a considerable decrease in biological activity.
Abstract: Die Struktur der Titelverbindung 1 ist offenbar ein neues antiplasmodisches Wirkungsprinzip, weil weder die Chinolinkomponente, noch der Sulfonamidanteil, noch die Art der Verknupfung ohne erhebliche Wirkungseinbuse verandert werden durfen. Structure Dependence of Antiplasmodic Activity of 3-[N-(4-Amidosulfonylphenyl)aminomethyl]-quinoline The title compound 1 seems to represent a new antiplasmodic structure. Neither the quinoline ring nor the sulfonamide group nor type and place of the attachement between them can be changed without a considerable decrease in biological activity.

Journal ArticleDOI
TL;DR: In this article, the reaction of N-alkoxy-2-hydroxycarboxamides with 1,1′-carbonyldiimidazole produces 3-benzyloxazolidine-2,4-diones.
Abstract: N-Alkoxy-2-hydroxycarbonsaureamide 3 reagieren mit 1,1′-Carbonyldiimidazol zu N-Alkoxyoxazolidin-2,4-dionen 4. Hydrolyse von N-(Tetrahydro-2H-2-pyranyloxy)-oxazolidin-2,4-dionen ergibt 3-Hydroxyoxazolidin-2,4-dione 5, die mit Phenylisocyanat zu 7 und mit Benzoylchlorid zu 8 umgesetzt werden. Die Benzylaminolyse von 4 liefert 3-Benzyloxazolidin-2,4-dione 10. 3-Alkoxyoxazolidine-2,4-diones from N-Alkoxy-2-hydroxycarboxamides and 1,1′-Carbonyldiimidazole Reaction of N-alkoxy-2-hydroxycarboxamides 3 with 1,1′-carbonyldiimidazole produces N-alkoxy-oxazolidine-2,4-diones 4. Hydrolysis of N-(tetrahydro-2H-2-pyranyloxy)oxazolidine-2,4-diones affords 3-hydroxyoxazolidine-2,4-diones 5 which are converted by the reaction with phenyl isocyanate into 7 and with benzoyl chloride into 8. Benzylaminolysis of 4 gave 3-benzyloxazolidine-2,4-diones 10.

Journal ArticleDOI
TL;DR: The 1,3-dicarbonyl compounds were obtained by reaction from methylthiosalicylate with α-bromoacetophenones 2 or 3 as mentioned in this paper.
Abstract: Die aus Thiosalicylsauremethylester und den α-Bromacetophenonen 2 oder 3 erhaltenen Alkylierungsprodukte 4 geben bei der Dieckmann-Kondensation die 1,3-Dicarbonylverbindungen 5, die mit Polyphosphorsaure (PPS) zu den Chinolonen 6 cyclisieren. 1,3-Dicarbonyl Compounds, XIII; Fused Quinolones, III: 5,11-Dihydrobenzothieno[3,2-b][1]quinolin-11-ones The S-alkylated products 4, obtained by reaction from methylthiosalicylate with α-bromoacetophenones 2 or 3, are converted to the 1,3-dicarbonyl compounds 5. These compounds cyclize to yield the quinolones 6 on heating with polyphosphoric acid (PPA).

Journal ArticleDOI
TL;DR: The 4-oxo-2-thioxotetrahydro-1,3-thiazines 1 and 2 were reacted with acid chlorides in the presence of triethylamine yielding the 3-acyl derivatives 3 and 4.
Abstract: Die 4-Oxo-2-thioxo-tetrahydro-1,3-thiazine 1 und 2 wurden in Gegenwart von Triethylamin mit Saurechloriden zu den 3-Acylderivaten 3 und 4 umgesetzt und deren Eigenschaften als Transacylierungsmittel am Beispiel der Hydrolyse, Alkoholyse und Aminolyse untersucht. 1,3-Thiazines, XI: 3-Acyl-4-oxo-2-thioxotetrahydro-1,3-thiazines, a new Type of Cyclic N,N-Bisacyldithiourethanes The 4-oxo-2-thioxotetrahydro-1,3-thiazines 1 and 2 were reacted with acid chlorides in the presence of triethylamine yielding the 3-acyl derivatives 3 and 4. These compounds were shown by hydrolysis, alcoholysis and aminolysis to be acylating agents.

Journal ArticleDOI
TL;DR: The pyranostilbenes 7a and b, 12, 19 and 28 were synthesized by ring closure reactions of substitute stilbene or through vinylene coupling of chromane as discussed by the authors.
Abstract: Die pyranring-kondensierten Stilbene 7a und b, 12, 19 und 28 wurden durch Ringschlusreaktionen aus substituierten Stilbenen oder durch Vinylen-Verknupfung von Chroman hergestellt. 1,2-Bis(benzopyranyl)ethene The pyranostilbenes 7a and b, 12, 19 and 28 were synthesized by ring closure reactions of substitute stilbenes or through vinylene coupling of chromane.



Journal ArticleDOI
TL;DR: The (methylthio)dithioacetates 2 and 3 have been prepared from the corresponding nitriles as mentioned in this paper, and the chlorination, oxidation, and methylation of the two compounds are described.
Abstract: Die Methylthio-dithioessigsaure-methylester 2 und 3 sind aus den zugehorigen Nitrilen erhaltlich. Ihre Chlorierung, Oxidation und Methylierung werden beschrieben. Thiono and Dithio Esters, XXVI: (Methylthio)dithioacetates The (methylthio)dithioacetates 2 and 3 have been prepared from the corresponding nitriles. Chlorination, oxidation and methylation of 2 and 3 are described.

Journal ArticleDOI
TL;DR: The N-substituierten 4-methylimidazoles 2 and 3 were prepared and tested for their histamine-like activity as discussed by the authors, and they showed no H2-antihistaminic activity.
Abstract: Es wurden die N-substituierten 4-[(2-Amino-ethylmercapto)-methyl]-imidazole 2 und 3 dargestellt und auf histaminartige Wirkung untersucht. Die Thioharnstoff- und Cyanoguanidin-Derivate von 3b zeigten keine H2-antihistaminische Wirksamkeit. H2-Antihistaminics, VI: Synthesis and Activity of N-Substituted 4-[(2-Aminoethylmercapto)methyl]imidazoles The N-substituted 4-[(2-aminoethylmercapto)methyl]imidazoles 2 and 3 were prepared and tested for their histamine-like activity. The thiourea and cyanoguanidine derivatives of 3b showed no H2-antihistaminic activity.

Journal ArticleDOI
TL;DR: The reaction of 4-hydroxy-2-quinolone (1a) with methyl iodide/potassium hydroxide in boiling acetone gave a mixture of 1-methyl-4-methoxy-2-, 1-3-dimethyl-4-, 4-methyl-2,quinoline (1b), and 1,3,3-trimethyl -2,4-dioxo-1,2,3.4-tetrahydroquinoline(2) as discussed by the authors.
Abstract: Bei der Reaktion des 4-Hydroxy-2-chinolons (la) mit Methyliodid/KOH in kochendem Aceton entsteht ein Gemisch aus 1-Methyl-4-methoxy-2-chinolon (1d), 1,3-Dimethyl-4-methoxy-2-chinolon (1e) und 1,3,3-Trimethyl-2,4-dioxo-1,2,3,4-tetrahydrochinolin (2). Als Nebenprodukt tritt 2,4-Dimethoxychinolin auf. Unter den gleichen Reaktionsbedingungen fuhrt 4-Methoxy-2-chinolon (1c) zu 1d, 1e, 2 und 3, wahrend 1-Methyl-4-hydroxy-2-chinolon (1b) 1d, 1e und 2 ergibt. Methylation of 4-Hydroxy-2-quinolone The reaction of 4-hydroxy-2-quinolone (1a) with methyl iodide/potassium hydroxide in boiling acetone gave a mixture of 1-methyl-4-methoxy-2-quinolone (1d), 1,3-dimethyl-4-methoxy-2-quinolone (1e), and 1,3,3-trimethyl-2,4-dioxo-1,2,3,4-tetrahydroquinoline (2). As by-product 2,4-dimethoxyquinoline (3) was identified. Under the same conditions 4-methoxy-2-quinolone (1c) yielded 1d, 1e, 2 and 3, while 1-methyl-4-hydroxy-2-quinolone (1b) gave 1d, 1e and 2.

Journal ArticleDOI
TL;DR: In this paper, the solubility in water, the temperature dependence of Silybin, Silydianin, and Silychristin, as well as the dissolution-pH profile of the title compounds were determined.
Abstract: Die Loslichkeit in Wasser, die Temperaturabhangigkeit der Loslichkeit, die Losungswarme und das Loslichkeits-pH-Profil der Titelsubstanzen wurden bestimmt. Physicochemical Properties of Silymarin, II: Solubility Parameters of Silybin, Silydianin, and Silychristin The solubility in water, the temperature dependence of the solubility, the heat of dissolution, and the dissolution-pH-profile of the title compounds were determined.

Journal ArticleDOI
TL;DR: In this paper, a method is described to determine paracetamol (acetaminophen) in blood samples by HPLC and electrochemical detection, which works well even in long-time experiments.
Abstract: Paracetamol im Serum wird mittels HPLC und elektrochemischer Detektion bestimmt. Zur Chromatographie an reversed phase (Rp8) Fertigsaulen gelangt enteiweistes Serum. Der gesamte Arzneistoff wird erfast, auch das plasmaeiweisgebundene Paracetamol. Die Bestimmungsgrenze liegt bei ca. 10ng/ml (S/N >10). Die relative Standardabweichung im gesamten untersuchten Konzentrationsbereich (50ng/ml - 4,5 ng/ml) betragt ca. 3%. Auch im Langzeitversuch arbeitet die Methode reproduzierbar und zuverlassig, wenn die moglichen Fehlerquellen beachtet werden. HPLC-Determination of Paracetamol in Serum by Electrochemical Detection A method is described to determine paracetamol (acetaminophen) in blood samples by HPLC and electrochemical detection. After precipitation of plasmaproteins the separation is done with manufactured columns containing reversed phase (Rp8) material. The detection limit is about 10 ng/ml (S/N >10) and the reproducibility is satisfactory (RSD <3% between 50 ng/ml and 4.5 μg/ml). The method works well even in long-time experiments.

Journal ArticleDOI
TL;DR: A particulate adenylate cyclase was prepared from cerebral cortex of rats which had been chronically treated with imipramine, indicating the development of adrenoceptor subsensitivity which is functionally retained in the cell‐free enzyme preparation.
Abstract: A particulate adenylate cyclase was prepared from cerebral cortex of rats which had been chronically treated with imipramine. Noradrenaline stimulated adenylate cyclase activity was significantly reduced compared to untreated controls. Neither total phosphodiesterase activity nor basal and maximal adenylate cyclase activity were altered by the imipramine treatment. This indicates the development of adrenoceptor subsensitivity which is functionally retained in the cell-free enzyme preparation. Verminderte adrenerge Sensitivitat einer zellfreien Adenylatcyclase aus Rattenhirn nach chronischer Imipramin-Behandlung. Eine partikulare Adenylatcyclase der Groshirnrinde von chronisch mit Imipramin behandelten Ratten wurde hergestellt. Es wurde gezeigt, das die durch Noradrenalin stimulierte Adenylatcyclaseaktivitat signifikant vermindert ist im Vergleich zu unbehandelten Kontrolltieren. Weder Phosphodiesterase noch basale oder maximale Adenylatcyclaseaktivitat werden durch chronische Imipramin-Behandlung verandert, was auf eine herabgesetzte noradrenerge Empfindlichkeit der Adenylatcyclase hinweist, die in der zellfreien Praparation funktionell erhalten bleibt.

Journal ArticleDOI
TL;DR: In this article, a new synthesis of Rutecarpine was proposed, which reacts with 2-nitrobenzyl chloride to yield the tertiary amine 2, which on reduction of the nitro group and dehydrogenating cyclization yields the pentacyclic amidine 4.
Abstract: 1,2,3,4-Tetrahydro-β-carbolin (1) wird mit 2-Nitrobenzylchlorid zum entsprechenden tertiaren Amin 2 umgesetzt, das nach Reduktion der Nitrofunktion und dehydrierender Cyclisierung zum pentacyclischen Amidin 4 reagiert. Anschliesende Oxidation gibt ein Gemisch aus Rutaecarpin (5) und dem korrespondierenden Dehydroprodukt 6, das chromatographisch getrennt werden kann. A New Synthesis of Rutecarpine 1,2,3,4-Tetrahydro-β-carboline (1) reacts with 2-nitrobenzyl chloride to yield the tertiary amine 2, which on reduction of the nitro group and dehydrogenating cyclization yields the pentacyclic amidine 4. Oxidation of 4 produces a mixture of rutecarpine (5) and the dehydrogenation compound 6, which are separated by chromatography.