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Showing papers in "Archiv Der Pharmazie in 1978"


Journal ArticleDOI
TL;DR: In this paper, the cycloadditions of substituted electron rich heteroaromatic compounds like furan, pyrrole, thiophene and N-methylimidazole with the s-cis-fixed azine system in 3,6-bis-(methoxycarbonyl)tetrazine and subsequent reactions are described.
Abstract: Wir beschreiben [4 + 2]-Cycloadditionen substituierter, elektronenreicher Heteroaromaten wie Furan, Pyrrol, Thiophen und N-Methylimidazol an das im 3,6-Dimethoxycarbonyl-tetrazin fixierte s-cis-Azinsystem und deren Folgereaktionen. „Inverse” Diels-Alder Additions, VII: π-Electron Rich Heteroaromatic Compounds as “Inverse” Dienophiles. We describe [4 + 2] cycloadditions of substituted electron rich heteroaromatic compounds like furan, pyrrole, thiophene and N-methylimidazole with the s-cis-fixed azine system in 3,6-bis-(methoxycarbonyl)tetrazine and subsequent reactions.

30 citations


Journal ArticleDOI
TL;DR: In this paper, the Mannich reaction was used to synthesize Pyrido[2,3d]pyrimidine-2,4diones (5-Deazapteridines) by condensation of 4-aminouracils with Mannich bases.
Abstract: 6,7-Substituierte Pyrido[2,3-d]pyrimidin-2,4-dione entstehen durch Kondensation von Aryl-alkanon-Mannichbasen bzw. ihren Hydrochloriden mit 4-Aminouracilen. Als Zwischenstufen werden 5,6-Dihydro-pyrido[2,3-d]pyrimidin-2,4-dione isoliert. Synthesis of Pharmacologically Active Heterocyclic Compounds by Application of the Mannich Reaction, III: Synthesis of Pyrido[2,3-d]pyrimidine-2,4-diones (5-Deazapteridines) Pyrido[2,3-d]pyrimidine-2,4-diones are prepared by condensation of 4-aminouracils with Mannich bases (or their hydrochlorides) of arylalkylketones. 5.6-Dihydropyridopyrimidines were isolated as intermediates.

28 citations


Journal ArticleDOI
TL;DR: The first tetronaure with anticoagulant activity was described in this article, where the activity strongly depends on the nature of the substituents at positions 3 and 5 of the parent molecule.
Abstract: Die ersten Tetronsauren mit blutgerinnungshemmender Wirkung werden beschrieben. Nach einmaliger oraler Verabreichung an Ratten (60-340 mg/kg) sank die Gerinnungsfahigkeit des Blutes (Quick-Zeit) auf weniger als 25% der Norm. Diese Werte wurden bereits nach 8-15 h erreicht. Die Wirksamkeit hangt von der Art der Substituenten in 3- und 5-Position der Tetronsaure ab. Die Beziehungen zwischen chemischer Struktur und biologischer Wirkung werden diskutiert. Anticoagulant Activity of 3,5-Disubstituted Tetronic Acids The first tetronic acids with anticoagulant activity are described. Eight to 15 h after oral administration of a single dose (60-340 mg/kg) to rats prothrombin levels < 25% were observed. The activity strongly depends on the nature of the substituents at positions 3 and 5 of the parent molecule. Structure-activity relationships are discussed.

27 citations


Journal ArticleDOI
TL;DR: In this paper, a method is described for the extraction of the active ingredients of the German Chamomile with supercritical gases, especially carbon dioxide and nitrous oxide, which can be obtained in good yields in the pressure range from 72 to 500 bar and at 31 to 80 °C.
Abstract: Es wird ein Verfahren zur Gewinnung von Kamillenwirkstoffen mit uberkritischen Gasen, insbesondere Kohlendioxid und Distickstoffoxid, beschrieben. Die Wirkstoffe Matricin, (−)-α-Bisabolol, die Bisabololoxide A und B sowie die En-In-Dicycloather lassen sich im Druckbereich von 72-500 bar bei 31 bis 80° unzersetzt und in guten Ausbeuten extrahieren. Die Flavonoide, Schleimstoffe und Ballaststoffe bleiben in der Droge zuruck. Die Wirkstoffgehalte im so gewonnenen Extrakt liegen uber den mit konventionellen Losungsmitteln erhaltenen. Die Zusammensetzung der Extrakte last sich durch stufenweise Extraktion und Abscheidung verandern. Extraction of German Chamomile with Supercritical Gases A method is described for the extraction of the active ingredients of the German Chamomile with supercritical gases, especially carbon dioxide and nitrous oxide. The active ingredients matricin, (−)-α-bisabolol and bisabolol oxides A and B as well as the en-yne-dicycloethers can be extracted undecomposed and in good yields in the pressure range from 72 to 500 bar and at 31 to 80 °C. The flavonoids, the mucous substances and roughage material remain in the drug. The percentage of the active ingredients in extracts thus obtained is higher than that of extracts obtained by conventional solvents. The composition of the extracts can be varied by stepwise extraction and separation.

23 citations


Journal ArticleDOI
TL;DR: In this article, a series of primary even numbered linear saturated alcohols from decanol up to octadecanol were determined with differential scanning calorimetry and were related with data of analogous alkanes.
Abstract: Angaben uber die Schmelzenthalpien und Schmelzentropien von Fettalkoholen fehlen in der Literatur ganz oder differieren sehr stark. Die Werte fur die homologe Reihe der primaren, geradzahligen und geradkettigen, gesattigten Alkohole der Kettenlange C10 bis C18 wurden differentialkalorimetrisch (Differential Scanning Calorimetry) bestimmt und zu den Daten der entsprechenden Alkane in Beziehung gesetzt. The Melting Enthalpy and Entropy of Fatty Alcohols Enthalpies and entropies of fusion of fatty alcohols are either unknown or show great discrepancies. Data for the homologous series of primary even numbered linear saturated alcohols from decanol up to octadecanol were determined with differential scanning calorimetry and were related with data of the analogous alkanes.

20 citations


Journal ArticleDOI
TL;DR: Inverse cycloadditions of various azepines as dienophiles with the s-cisazine system in 3,6-dimethoxycarbonyl-tetrazine were reported in this paper.
Abstract: Wir beschreiben „inverse” [4+2]-Cycloadditionsreaktionen mit verschiedenen Azepinen als Dienophile gegenuber dem in 3,6-Dimethoxycarbonyl-tetrazin fixierten s-cis-Azinsystem. Die Azepine 2, 8 und 15 reagieren mit ihrer π-Bindung in 4,5-Position, am 2-Diathylamino-3H-azepin (11) erfolgt zweifache Cycloaddition. “Inverse” Diels-Alder Additions, VIII: Azepines as “Inverse” Dienophiles. We describe “inverse” [4+2]-cycloadditions of various azepines as dienophiles with the s-cis-azine system in 3,6-bis(methoxycarbonyl)tetrazine. The azepines 2, 8 and 15 react with their 4,5-π-bonds. In the case of 2-diethylamino-3H-azepine (11) twofold cycloaddition was observed.

19 citations


Journal ArticleDOI
TL;DR: In this paper, a new nitrogen-containing substance siamine has been isolated from seeds and leaves of Cassia siamea by means of an independent synthesis, which has been identified as 3methyl-6,8-dihydroxyisoquinol-1-one.
Abstract: Bluten und Blatter von Cassia siamea enthalten Anhydrobarakol-Hydrochlorid (1) und das verwandte 5-Acetonyl-7-hydroxy-2-methylchromon (4). Als neue stickstoffhaltige Substanz wurde aus Samen und Blattern Siamin isoliert und seine Struktur als 3-Methyl-6,8-dihydroxy-isochinolon-(1) (16) durch Synthese bewiesen. Constituents of Cassia Siamea Flowers and Leaves of Cassia siamea contain anhydrobarakol hydrochloride (1) and the related 5-acetonyl-7-hydroxy-2-methylchromone (4). As a new nitrogen-containing substance siamine has been isolated from seeds and leaves. It has been identified as 3-methyl-6,8-dihydroxyisoquinol-1-one (16) by means of an independent synthesis.

19 citations




Journal ArticleDOI
TL;DR: A variety of pilocarpus microphyllus Stapf contains a new isomeric base instead of the usual side alkaloid pilosine in addition to the main one as mentioned in this paper.
Abstract: Von Pilocarpus microphyllus Stapf gibt es eine Varietat, die auser dem Hauptalkaloid Pilocarpin anstelle des ublichen Nebenalkaloides Pilosin eine neue, isomere Base enthalt. Von den vier moglichen Stereoisomeren des Pilosins sind bisher drei bekannt: Pilosin, Isopilosin und Epiisopilosin. Bei dem neuen Alkaloid handelt es sich nicht um das in dieser Reihe noch fehlende Epipilosin. Durch 13C-NMR-Spektroskopie wurde nachgewiesen, das die Verknupfung des Benzylhydroxylactonringes mit dem Imidazolring uber die CH2-Gruppe nicht wie bei den Pilosinen an C-5 erfolgt, sondern an C-4. Epiisopiloturine, A New Pilocarpus Alkaloid A variety of pilocarpus microphyllus Stapf contains a new isomeric base instead of the usual side alkaloid pilosine in addition to the main alkaloid pilocarpine. Of the four possible stereoisomers of pilosine three are known so far: pilosine, isopilosine and epiisopilosine. The new alkaloid is not the still unknown fourth alkaloid of this series (epipilosine). It was shown by 13C-nmr spectroscopy that the benzyloxylactone ring is not linked with the imidazole ring by the CH2-group at C-5 - as is the case with the pilosines - but rather at C-4.

17 citations


Journal ArticleDOI
TL;DR: Structural-activity relationships of six new 1,2,3,4-tetrahydro-β-carbolines were investigated and the most active compound 4b has a profile similar to that of Chloropromazine.
Abstract: Die Beziehungen zwischen Struktur und neuropsychotroper Wirkung bei 6 neuen 1,2,3,4-Tetrahydro-β-carbolinen werden untersucht. Die aktivste Verbindung 4b hat ein pharmakologisches Profil, das dem Chlorpromazin ahnelt. Keine der Substanzen hat dopaminerge Eigenschaften. Dopamine Analogous 1,2,3,4-Tetrahydro-β-carbolines Structure-activity relationships of six new 1,2,3,4-tetrahydro-β-carbolines were investigated. The most active compound 4b has a profile similar to that of Chloropromazine. None of the compounds exhibit dopaminergic activities.

Journal ArticleDOI
TL;DR: The synthesis of o-tert is described in this article, where aminobenzamides and quinazolinones are derived from aminophenylharnstoffen.
Abstract: Es wird die Synthese beschrieben von o-tert. Aminobenzamiden, die bei der Quecksilber(II)-AeDTA-Dehydrierung kondensierte Chinazolinone liefern. Die entsprechende Umsetzung von o-tert. Aminophenylharnstoffen verlauft unter Spaltung der Nachbargruppe zu kondensierten Benzimidazolen. Cyclodehydrogenation of Aniline Derivatives Carrying Carboxamide or Urea Functions The synthesis of o-tert. aminobenzamides is described. Dehydrogenation of these compounds with mercury(II)-EDTA yields condensed quinazolinones. The analogous reaction of o-tert. aminophenylureas leads to condensed benzimidazoles with simultaneous removal of the aminocarbonyl group.

Journal ArticleDOI
TL;DR: The synthesis of α-substituted 5-methyl-4- {2-[3-(methyl)thioureido]ethylthiomethyl}-1H-imidazoles 4 from α substitituted 4-methoxymethyl-5methyl-5-methyl 1H-IMIDazoles 2 is described in this article.
Abstract: Es wird die Synthese α-substituierter 5(4)-Methyl-4(5)-[[2-(N′-methyl-thioureido)-athylmercapto]-methyl]-imidazole4 aus α-substituierten 4(5)-Methoxymethyl-5(4)-methyl-imidazolen 2 sowie die H2-antihistaminische Wirksamkeit der dargestellten 4 beschrieben. H2-Antihistaminics, II: Synthesis and Pharmacology of α-Substituted Metiamide Analogues The synthesis of α-substituted 5-methyl-4- {2-[3-(methyl)thioureido]ethylthiomethyl}-1H-imidazoles 4 from α-substituted 4-methoxymethyl-5-methyl-1H-imidazoles 2 is described. The H2-antihistaminic activity of the products is reported.


Journal ArticleDOI
TL;DR: The phlorotannins of Cystoseira baccata (Gmelin) Silva, a brown alga belonging to the fucales, have been isolated by means of their acetyl derivatives as mentioned in this paper.
Abstract: Die Phlorotannine der zu den Fucalen gehorenden Braunalge Cystoseira baccata (Gmelin) Silva wurden uber ihre Acetylderivate isoliert. Folgende Verbindungen wurden eindeutig identifiziert: Phloroglucintriacetat (1), Bifuhalolhexaacetat (3), Difucolhexaacetat (4), Fucophlorethol-Boctaacetat (6) und Fucodiphlorethol-B-dekaacetat (8). Das Vorkommen von Trifuhaloloctaacetat (5) und einem Tetraphloretholnonaacetat (7) konnte wahrscheinlich gemacht werden. Antibiotics from Algae, XX: Low-Molecular Phlorotannins from Cystoseira Baccata. The phlorotannins of Cystoseira baccata (Gmelin) Silva, a brown alga belonging to the fucales, have been isolated by means of their acetyl derivatives. The following compounds were identified: Phloroglucinol triacetate (1), bifuhalol hexaacetate (3), difucol hexaacetate (4), fucophlorethol-B octaacetate (6) and fucodiphlorethol-B decaacetate (8). The presence of trifuhalol octaacetate (5) and of a tetraphlorethol nonaacetate (7) seems probable.

Journal ArticleDOI
TL;DR: Pyridine analogues of Fentanyl were synthesized and tested for analgesic activity according to the hot-plate procedure with mice and for respiratory depressive action in the rabbit in this article.
Abstract: Es wurden Pyridin-Analoga vom Fentanyl-Typ synthetisiert und im hot-plate-Test auf analgetische und am Kaninchen auf atemdepressive Wirkung gepruft. Synthesis and Pharmacological Screening of Fentanyl Analogues Pyridine analogues of Fentanyl were synthesized and tested for analgesic activity according to the hot-plate procedure with mice and for respiratory depressive action in the rabbit.

Journal ArticleDOI
TL;DR: In this paper, the enaminoketones 3 and 6 with the CH-acidic compounds 7 and 16 lead to polymethine derivatives 8 and 18, which react with alkylating agents, such as the aminalester 2, the amide acetal 13 and with CH acidic compounds.
Abstract: Reaktionen der Enaminoketone 3 und 6 mit den CH aciden Verbindungen 7 und 16 fuhren zu den Polymethin-Derivaten 8 und 18, die mit Alkylierungsmitteln, mit dem Aminalester 2, dem Amidacetal 13 sowie CH-aciden Verbindungen umgesetzt werden. Reactions of Enaminoketones with CH-acidic Compounds Reactions of the enaminoketones 3 and 6 with the CH-acidic compounds 7 and 16 lead to the polymethine derivatives 8 and 18, which react with alkylating agents, the aminalester 2, the amide acetal 13 and with CH-acidic compounds.


Journal ArticleDOI
TL;DR: In this paper, a suser Geschmack is vorhanden, sobald der Zucker selber sus schmeckt und sich am Aglykon in entgegengesetzter Stellung zur Glykosidbindung eine hydrophile Gruppe befindet.
Abstract: Zum Verstandnis des susen Geschmacks des Glycyrrhizins werden von 18β-Glycyrrhetinsaure und einigen ihrer Derivate Glykoside der Glucose, der Glucuronsaure und der Lactose hergestellt. Ein suser Geschmack ist vorhanden, sobald der Zucker selber sus schmeckt und sich am Aglykon in entgegengesetzter Stellung zur Glykosidbindung eine hydrophile Gruppe befindet.

Journal ArticleDOI
TL;DR: A number of unknown disubstituted 3‐phenylsydnones are synthesized and subjected for preliminary screening and methyl, bromo and chloro groups in the phenyl ring of 3‐tolylsydnone enhance the CNS depression action while the methyl group in the 4‐position of the sydnone ring does not add to the CNS depressed action shown by the original syd none.
Abstract: A number of unknown disubstituted 3-phenylsydnones are synthesized and subjected for preliminary screening. Methyl, bromo and chloro groups in the phenyl ring of 3-tolylsydnones enhance the CNS depression action while the methyl group in the 4-position of the sydnone ring does not add to the CNS depression action shown by the original sydnone. Synthese und zentraldepressive Eigenschaften disubstituierter Sydnone Eine Anzahl noch nicht bekannter disubstituierter 3-Phenylsydnone wird synthetisiert und einem vorlaufigen Screening unterworfen. Methyl-, Brom- und Chlorsubstitution im Phenylring von 3-Tolyl-sydnonen verstarken die zentraldepressive Wirkung, wahrend eine Methylgruppe in 4-Stellung des Sydnonringes die zentraldepressive Wirkung im Vergleich zum Ausgangssydnon verringert.



Journal ArticleDOI
TL;DR: Fomocaine is well absorbed by the buccal mucosa from an aqueous solution at pH 8, but only poorly absorbed at pH 4.5, which partially explains the prolonged topical anesthetic effect of fomocane.
Abstract: Fomocaine is well absorbed by the buccal mucosa (about 70 % in 5 minutes) from an aqueous solution at pH 8, but only poorly absorbed at pH 4. However, it does not pass directly through the membrane into the blood stream, but is bound to the membrane for a prolonged period. About 30 % of the absorbed dose may be recovered from the mucosa one hour after the initial buccal test, which partially explains the prolonged topical anesthetic effect of fomocaine. Das Resorptionsverhalten von Fomocain bei bukkaler Applikation Fomocain wird von der Mundschleimhaut aus wassriger Losung bei pH 8 gut (etwa 70 % in 5 min), aber bei pH 4 nur noch schwach absorbiert. Die Substanz gelangt jedoch nicht direkt durch die Membran in den Blutkreislauf, sondern wird von der Membran fur langere Zeit gebunden. Etwa 30 % der absorbierten Dosis kann 1 Std. nach dem ersten Resorptionsversuch von der Schleimhaut zuruckgewonnen werden. Dies erklart teilweise den langdauernden oberflachenanasthetischen Effekt von Fomocain.

Journal ArticleDOI
TL;DR: The mustard compounds 8 and 15 are synthesized as potential mammatropic antineoplastics starting from diethylstilbestrol and hexestrol, respectively, and both compounds are irreversibly bound to the cytoplasmic estrogen receptor as discussed by the authors.
Abstract: Ausgehend von Diathylstilbostrol bzw. Hexostrol werden die Lostverbindungen 8 und 15 als potentielle mammatrope Antineoplastica synthetisiert. Beide Verbindungen werden irreversibel an den cytoplasmatischen Ostrogenrezeptor gebunden. Die Rezeptoraffinitat ist um den Faktor 104 niedriger als die des Ostradiols. Potential Antineoplastics, III: N-Mustard Derivatives of Diethylstilbestrol and Hexestrol with Free Phenolic Hydroxy Groups The mustard compounds 8 and 15 are synthesized as potential mammatropic antineoplastics starting from diethylstilbestrol and hexestrol, respectively. Both compounds are irreversibly bound to the cytoplasmic estrogen receptor. The binding affinitiy is 104 times lower than that of 17β-estradiol.

Journal ArticleDOI
TL;DR: The synthesis and pharmacological properties of several polymethylated bicyclic alcohols with choleretic activity is reported in this paper, where the synthesis of potential cholagogues is discussed.
Abstract: Es wird uber die Synthese und die pharmakologischen Eigenschaften einer Reihe von mehrfach methylierten bicyclischen Alkoholen mit choleretischer Aktivitat berichtet. Synthesis of Potential Cholagogues. Structure-Activity Relationships of Bicyclo[2.2.1]heptyl Alkyl Carbinols The synthesis and pharmacological properties of several polymethylated bicyclic alcohols with choleretic activity is reported.


Journal ArticleDOI
TL;DR: The alkaloids Catuabine A, B and C are the hitherto unknown diesters of tropane-3,7-diol, as shown by 1H-NMR spectroscopy, all three esters have α-configuration at C-3.
Abstract: Die Alkaloide Catuabin A (1) (0,01%) Catuabin B (2) (0,0005%) und Catuabin C (3) (0,00064%) werden anhand der spektroskopischen Daten, Elementaranalysen und Molekularmassen sowie durch Vergleich mit bekannten Strukturen als bisher unbekannte Diester des Tropan-3,7-diols identifiziert. Laut 1H-NMR-Spektroskopie haben alle drei Ester an C-3 α-Konfiguration, laut 13C-NMR-Spektroskopie an C-7 β-Konfiguration. Die Sauren sind: am C-3 3,4,5-Trimethoxybenzoesaure (A und B) resp. Pyrrol-2-carbonsaure (C), an C-7 N-Methyl-pyrrol-2-carbonsaure (A und C) resp. Benzoesaure (B). Fur Catuabin A wird eine vollstandige 13C-NMR-Signalzuordnung angegeben. Alkaloids from Erythroxylum Vacciniifolium Martius, II: The Structures of Catuabine A, B, and C The alkaloids Catuabine A (1), B (2) and C (3) are the hitherto unknown diesters of tropane-3,7-diol. As shown by 1H-NMR spectroscopy, all three esters have α-configuration at C-3. The configurations at C-7 are β, according to the 13C-NMR spectra. 3,4,5-Trimethoxybenzoic acid (A and B) and pyrrole-2-carboxylic acid (C) are bound at C-3. N-Methylpyrrole-2-carboxylic acid (A and C) and benzoic acid (B) are bound at C-7. A complete interpretation of the 13C-NMR-spectrum of Catuabine A is given.

Journal ArticleDOI
TL;DR: In this paper, 2-trichloromethyl-1,2-ethanesultone reacts with nitrogen compounds of suitable basicity to derivatives of DL-2-hydroxy-3, 3,3,3 trichloropropanesulfonic acid.
Abstract: 2-Trichlormethyl-1,2-athansulton (1) reagiert mit Stickstoffbasen ausreichender Basizitat zu DL-2-Hydroxy-3,3,3-trichlor-propansulfonsaure-derivaten. Investigations on β-Sultones, I: Reactions of 2-Trichloromethyl-1,2-ethanesultone with Nitrogen Bases. 2-Trichloromethyl-1,2-ethanesultone (1) reacts with nitrogen compounds of suitable basicity to derivatives of DL-2-hydroxy-3,3,3-trichloropropanesulfonic acid.

Journal ArticleDOI
TL;DR: In this article, a Mannich condensation of several nitroalkanes with formaldehyde and amino acids at room temperature and with catalysis by alkali or mineral acid leads to 5-nitrohexahydropyrimidine-1,3-dicarboxylic acids.
Abstract: Die Mannichkondensation verschiedener Nitroalkane mit Formaldehyd und Aminosauren fuhrt bei Raumtemperatur in Gegenwart von sauren oder basischen Katalysatoren zu den entsprechender 5-Nitro-hexahydropyrimidin-1,3-dicarbonsauren. Mit Athylendiamin-N, N-diessigsaure werden 6-Nitro-1,4-diazacycloheptan-1,4-dicarbonsauren erhalten. Synthesis of Polyfunctional Heterocyclic Compounds by Aminoalkylation of Nitroalkanes Mannich condensation of several nitroalkanes with formaldehyde and amino acids at room temperature and with catalysis by alkali or mineral acid leads to 5-nitrohexahydropyrimidine-1,3-dicarboxylic acids. With ethylenediamine-N,N-diacetic acid, 6-nitro-1,4-diazacycloheptane-1,4-dicarboxylic acids are obtained.

Journal ArticleDOI
TL;DR: In this article, secondary metabolites from aqueous extracts of Ononis spinosa L. (Papilionaceae) were isolated beside the known apolar components (derivatives of sterols, triterpenes, isoflavonoids and pterocarpane).
Abstract: Aus dem wasrigen Extrakt der Ononis spinosa L. (Papilionaceae) konnten neben den bereits bekannten apolaren Sterol-, Triterpen-, iso-Flavonoid- und Pterocarpanderivaten 7-Demethoxy-7-β-D-glucosyloxy-Homopterocarpin, 7-β-D-glucosyloxy-ϕ-Baptigenin und 2,3-Dihydro-Ononin isoliert werden. Nach Ansicht der Verfasser handelt es sich bei den isolierten Verbindungen um neue naturliche Substanzen. Secondary Metabolites from Aqueous Extracts of Ononis Spinosa L. 7-Demethoxy-7-(β-D-glucosyloxy) homopterocarpine, 7-β-D-glucosyloxy-ϕ-baptigenine and 2,3-dihydro-ononine were isolated beside the known apolar components (derivatives of sterols, triterpenes, isoflavonoids and pterocarpane) from aqueous extracts of Ononis spinosa L. (Papilionaceae). The isolated compounds are new natural products.