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Da die Frage die wertvollste Sprachleistung des Menschen ist, die entweder ein Gesprach nach sich zieht, eine Erlauterung verlangt oder zum Nachdenken herausfordert, sollen die zum Thema Vitamine gehorenden Begriffe, Definitionen, Anschauungen, Fakten und Vorstellungen interrogativ behandelt werden.

Als Kulturlandschaft von hoher okologischer Bedeutung ist die Westerwalder Seenplatte einmalig fur Rheinland-Pfalz und das Rheinische Schiefergebirge. Als Brut- und Rastgebiet bestandsbedrohter Arten, Lebensraum von Reptilien und Amphibien sowie aufgrund seiner seltenen Verlandungs- und Teichbodengesellschaften steht ein Teil des innerhalb von 300 Jahren entstandenen Areals unter Naturschutz.

Despite the very close structural relationship between dapsone (4,4′-diaminodiphenyl sulfone, 4,4′ sulphonyldianiline, diaphenyl sulphone, DDS) and sulfanilamide (p-aminobenzene sulfonamide), being the prototype of all other sulfonamides, only dapsone shows remarkable efficient pharmacological activity against Mycobacterium leprae. Cells of certain micro-organism need para-aminobenzoic acid (PABA), the latter playing the role of natural substrate to biosynthesis of folic acid. Sufones and sulfonamides show competitive antagonism as chemical analogs of PABA. It is most surprising that, despite of sharing this molecular mechanism, only dapsone shows anti-leprosy activity in vivo. The study was accomplished using molecular mechanics (SYBYL) and semiempirical methods (MOPAC). The calculations of aromaticity, charges, protonation by MOPAC, and of lipophilicity by our empirical program LIPOP(hilicity) give evidence that dapsone is more lipophilic (log P values 0.97) than sulfanilamide (-0.67). The extremely lipophilic cell wall of Mycobacterium leprae contributes to the surprising difference in anti-leprosy activity. Sulfonamides are more or less deprotonated (45 to 99 %) at physiological pH units, whereas dapsone is totally undissociated. This results in different permeability rates into the bacterial cells in vivo. Compared to other sulfones and sulfonamides, the unique combination of high lipophilicity and low ionic dissociation favors anti-leprotic potency in dapsone. On principle, amide groups do not hinder activity, but cause acidity and subsequently dissociation.

The inclusion of organic molecules to different calixarenes was investigated both experimentally and theoretically. Experimental data were obtained for various calixarenes of different thicknesses interacting with perchloroethylene, chloroform, benzene and toluene at different partial pressures and temperatures. The amount of included molecules was monitored by frequency responses of mass-sensitive bulk acoustic wave devices. To estimate ‘key-lock’ binding energies, the activation energy of desorption was determined experimentally from thermodesorption spectroscopy. The host/guest interaction energies were calculated theoretically with the TRIPOS force field approach which, in contrast to current quantum chemical approaches (MOPAC/AM1, MOPAC/PM3), gave satisfactory distance-dependent energy minima. Experimentally observed changes in the binding energies for the inclusion of C 2 Cl 4 , CHCl 3 , CH 3 C 5 H 6 and C 6 H 6 molecules in calixarenes agree surprisingly well with results with theoretical calculations.

Modified calixarenes can be used as model compounds to study molecular recognition since their molecular cavities reversibly incorporate small organic molecules. This effect has been used in chemical sensors with bulk and surface acoustic wave devices, coated with thin calixarene layers. These devices sensitively convert the mass changes during molecule/calixarene interactions into electronic signals. Thin films of modified calixarenes were prepared with various side groups and various sizes by Knudsen sublimation under well-defined, ultra-high-vacuum conditions. The interaction with perchloroethylene, chloroform, benzene, and toluene at constant temperatures, T, and partial pressures, pi, was studied systematically for different film thicknesses, d, by means of mass changes Δm=f(T,p i,d). From the thickness dependence of values, Δmeq, obtained under thermodynamic equilibrium conditions, surface and bulk effects during molecule calixarene interactions were separated. Pronounced excesses of surface concentrations of organic molecules have been found. Activation energies for molecular desorption from surface sites and for diffusion to subsurface sites were determined from mass spectroscopic results of thermal desorption behaviour. Experimental data of adsorption and desorption energies were confirmed by theoretical force field calculations.

Transient membrane holes induced by sodium cholate (Schubert et al., 1986, Biochemistry 25, 5263–5269) were used to encapsulate molecules at least up to M r = 70,000 into preformed liposomes. High trapping efficiencies (TE) close to 50% were achieved with concentrated suspensions of liposomes independent of their lamellarity, which was evaluated by cryomicroscopy of cryofixated suspensions. Another suitable hole-forming detergent is n -octyl β- d -glucopyranoside. Maximum trapping efficiency was measured within a narrow concentration range of added detergent below the onset of membrane solubilization. Using pure egg yolk lecithin (egg PC) or egg PC/bovine brain phosphatidylserine (7:3 mol/mol), trapping efficiency compared with the ratio of the volume inside the liposomes to the total aqueous volume in the samples. Therefore, it is probable that solutes that have been added to the external liposomal space diffuse into the liposomes, when the membranes are opened for several minutes. TE is slightly reduced by 30 mol% cholesterol in the membrane or if highly concentrated protein solutions (insulin or hemoglobin) or molecules with elongated form (polyuridylic acid) are to be encapsulated. An especially low TE into DPPC liposomes at 25°C is indicative of suppressed hole formation in the gel phase of the membrane. The residual amount of detergent after rechromatography of the loaded liposomes and liposome alterations are negligible. Detergent-induced liposome loading (DILL) is a convenient method for entrapping small molecules, larger carbohydrates, proteins, and nucleic acids into preformed liposomes with membranes in the liquid crystal phase. In addition, the ratio of calculated to found trapping efficiency of inulin is a suitable value for the mean lamellarity of vesicles up to a diameter of 200 nm.

The synthesis of azathia-analogues of the platelet activating factor containing a methioninol backbone is reported. The preparation starts with a cylating methionine ethyl ester-HCl with palmitoyl chloride to form the amide linkage. Following ester reduction the phosphocholine part is introduced via 2-chloro-2-oxo-1,3,2-dioxaphospholane and subsequent ring opening with trimethylamine under pressure. Two related compounds, the sulfoxide and the sulfone, are obtained by oxidation with 3-chloroperbencoic acid. In addition the sulfoxide derivative is prepared starting with d - and l -methionine ethyl ester-HCl.

16 Knochen wurden im Jahr 1856 aus einem Steinbruch im Neandertal geborgen. Um ein Haar ware der Neandertalfund – dessen 150. Jahrestag in diesem Jahr ausgiebig gefeiert wird – im Schutt gelandet. Nur weil ein Steinbruchbesitzer “Sauerier” witterte, stoppte er seine Arbeiter, lies im “Lehm” nachsuchen und den als Steinsammler bekannten Lehrer Fuhlrott benachrichtigen. Und der tippte richtig auf Knochen eines fossilen Menschen.

A method for the sensitive determination of the sulphopeptide lipoxins (LXs) C4, D4 and E4 by high-performance liquid chromatography with subsequent electrochemical detection is described. The best results were obtained when the analysis was carried out with the solvent system methanol-water-trifluoroacetic acid (66:34:0.008, v/v/v). The acquired half-wave potentials were different for all investigated compounds: +1.18 V for LXC4 +1.3 V for LXD4 and +1.25 V for LXE4. The detection limits of LXC4, LXD4 and LXE4, based on a signal-to-noise ratio of 3:1, were found to be 200-700 fmol. Although sulphopeptide lipoxins possess a high molar absorptivity, electrochemical detection still is three times more sensitive than ultraviolet detection.

Various S-substituted thiosuccinimides 1a-d and thiophthalimides 2a-d were found to react with trialkylphosphites according to a Michaelis-Arbuzov type mechanism. This provides an efficient way to prepare thiophosphoric acid esters, particularly thiophospholipids, with a C-S-P bond.

Es werden homologe Liposomenbausteine 3 mit L-Cystein als chirale hydrophile Kopfgruppe synthetisiert. Als Verknupfungseinheit zwischen Cystein und den lipophilen Alkylketten dient s-Triazin. Mittels DSC- und Fluoreszenz-Anisotropie-Messungen lassen sich die Phasenubergangstemperaturen der Lipide bestimmen. Es kann gezeigt werden, das eine den Phospholipiden analoge Relation zwischen Art und Lange der Ketten und der Phasenubergangstemperatur besteht. Einschlusversuche mit ionischen wasserloslichen Farbstoffen ergeben Hinweise auf eine Interaktion der in Phosphatpuffer (pH = 7.0), gebildeten Vesikel mit kationischen, nicht jedoch mit anionischen hydrophilen Substanzen. Synthesis and Aggregation Behaviour of Chiral Cysteine Amphiphiles with s-Triazine as Connecting Unit Several homologous liposome building blocks 3 with L-cysteine as chiral hydrophilic head group are synthesized. s-Triazine serves as connecting unit between cysteine and the lipophilic alkyl chains. The phase transition temperatures of the lipids are determined by DSC or fluorescence anisotropy. It can be shown, that the relationship between nature and length of the chains and the phase transition temperature corresponds to that of phospholipids. Encapsulation experiments with ionic water-soluble dyes give some hints that the vesicles prepared in phosphate buffer (pH = 7.0) interact with cationic but not with anionic hydrophilic substances.

Es wird uber eine einfache, vom 5-Chlormethyl-8-hydroxychinolin ausgehende Synthese von N,N′-Tetra-(8-hydroxychinolylmethyl)-α,ω-diaminoalkanen und deren komplexierende Eigenschaften berichtet. Synthesis and Complexing Properties of N,N,N′,N′-Tetrakis-(8-hydroxy-5-quinolylmethyl)-α,ω-diaminoalkanes A simple synthesis of N,N,N′,N′-tetrakis-(8-hydroxy-5-quinolylmethyl)-α,ω-diaminoalkanes, starting from 5-chloromethyl-8-hydroxyquinoline (basic material), and the complexing properties of these compounds are described.

Die Reaktion des Antihistaminicums Promethazin mit Nitrit bei 37° wurde untersucht. Ein Verfahren zur DP-polarographischen Bestimmung des entwickelten NDMA in Konzentrationen bis zu 5 × 10−6 mol/l wird beschrieben. Storende Depolarisatoren wurden durch Destillation im Vakuum unterhalb 60° abgetrennt. The Formation of Nitrosamine from Drugs, III: Quantitative Determination of N-Nitrosodimethylamine Formed from Promethazine and Nitrite The reaction of nitrite with the antihistaminic promethazine at 37°C was studied. A procedure for the polarographic determination of N-nitrosodimethylamine at concentrations of about 5 × 10−6 M is proposed. Separation from interfering depolarisators was achieved by distillation in vacuum below 60°C.

Benzoylacetimidsaure-ethylester (1a) und seine Derivate 1b, 1c sowie Benzoylacetamidin (2a) liegen in Losung in der Enolform vor. Mit Keton-Mannichbasen setzen sie sich zu 2-Amino-3-pyridyl-phenylketonen um. Heterocycles via Mannich Condensation, VI: Syntheses of 2-Amino-3-pyridylphenyl Ketones The ethyl 2-benzoylacetimidates 1a-c and 2-benzoylacetamidine (2a) exist in solution as enols. Ketonic Mannich bases condense with 1a-c and 2a to yield 2-amino-3-pyridylphenyl ketones.

Chinaalkaloide zeigen bei Einschlusuntersuchungen in Liposomen mit negativem Oberflachenpotential hohe Membranbindungsraten. Die Interaktion beruht auf elektrostatischen Wechselwirkungen zwischen negativ geladenen Lipidkopfgruppen und den Chinaalkaloiden, welche kationischen Charakter besitzen. Neutrale und positiv geladene Membranen aus ungesattigten Lipiden stellen praktisch keine Diffusionsbarriere dar. Bindungsstudien von Chinin an Erythrocyten zeigen, das der asymmetrische Membranaufbau der Zellen eine wichtige Rolle fur die Aufnahme der Blutschizontenmittel in ihren Wirkort spielt. Liposomes as Drug Carrier for Cinchona Alkaloids and as a Model for the Interaction of Cinchona Alkaloids with the Red Blood Cell Encapsulation studies in negatively charged liposomes reveal high membrane binding rates for the cinchona alcaloids. The binding is based on electrostatic interactions between the negatively charged lipid headgroups and the cinchona alcaloid molecules, which have cationic character. Neutral and positively charged membranes composed of unsaturated lipids virtually appear to be no barriers for the diffusion of these substances. Binding studies of quinine to Red Blood Cells (RBC) reveal, that the asymmetric structural principle of the RBC-membrane plays an important role for the uptake of the blood schizontoidal drugs into their domains.

Enaminonitrile der Furan- bzw. Thiophenreihe werden auf ihr Verhalten gegenuber Licht und Sauerstoff untersucht. Es werden Verbindungen erhalten, die bisher nicht auf photochemischem Weg zuganglich waren. The Stability of Heterocyclic α-Enaminonitriles Enaminonitriles of the furane and thiophene series were investigated with regard to their reactions with light and oxygen. The compounds obtained were previously not accessible by photochemical processes.

N-sekundare 3-Aminopropiophenone, die in Position 2 eine Phenyl- oder Methylgruppe tragen, erleiden bei der UV-Bestrahlung hauptsachlich eine Photodehydrierung. Research in Photochemical Synthesis of Ephedrine-like Compounds, II. Photodehydration of 3-Amino-propiophenones UV-Irradiation of N-secondary 3-amino-propiophenones, which have a phenyl or methyl group in position 2, yields mainly the photodehydration compounds.

The synthesis of the difficult to obtain pyrrolo[2,3-d]pyrimidine-2,4-diamine (4) is reported. Furthermore, some unexpected reactions on the 2-aminopyrrole-3-carbonitrile system are described 15-17.

Die Bestrahlung von Phthalimid in einem, Gemisch von Dioxan und Aceton fuhrt zu den Photoprodukten 1 bis 4; in Isopropanol entstehen 2 bis 4; in Athanol 2, 3 und 5; in Methanol 2 und 3. Photoreactions of Phthalimide Irradiation of phthalimide in a mixture of dioxane and acetone leads to the photo compounds 1, 2, 3 and 4; in isopropanol 2, 3 and 4, in ethanol 2, 3 and 5, in methanol 2 and 3 are produced.

Synthesis of 2-Amino-3-nitropyridines and -1,4-dihydropyridines The title compounds 4 and 5 can be synthesized from the primary nitroketene animal 2 and 1,3-biselectrophiles like β-aminoketones (ketonic Mannich bases) or enaminoketones.

Die Titelverbindungen 3 und 4 lassen sich sowohl aus dem Nitroketen-O,N-acetal 1 und prim. bzw. sekund. Aminen als auch durch sukzessive Amino- und Ammonolyse des Nitroketen-S,S-acetals 2 gewinnen. Die Reaktion von 2 mit wasrigem Ammoniak fuhrt zum dimeren Nitroacetonitril 9. Syntheses of Primary Nitroketene Aminals The title compounds 3 and 4 were obtained from the nitroketene O,N-acetal 1 and primary or secondary amines, as well as by successive amino- and ammonolysis of the nitroketene S,S-acetal 2. The reaction of 2 with aquous ammonia leads to the dimeric nitroacetonitrile 9.

Die Titelverbindungen 4 werden durch N-7-Dealkylierung der 2-Furanylmethyl-, 2-Thiophenylmethyl-, oder 1-Phenylethyl-Gruppe aus den Derivaten 2a – g und 10a – j mit Polyphosphoraure erhalten. Im Gegensatz zur 2-Furanylmethyl-Gruppe lassen sich die 2-Thiophenylmethyl- und 1-Phenylethyl-Gruppen unabhangig von der Substitution am Heterobicyclus entfernen. Synthesis of 7-Unsubstituted 7H-Pyrrolo[2,3-d]pyrimidines The title compounds 4 are obtained by N-7 dealkylation of the 2-furanylmethyl, 2-thio-phenylmethyl, or 1-phenylethyl group from 2a – g and 10 – j with polyphosphoric acid. In contrast to the 2-furanylmethyl group the 2-thiophenylmethyl and 1-phenylethyl group can be removed independently of the substitution of the heterobicycle.

Es wird ein Syntheseweg zur Darstellung von 10-Alkylthio-5H-dibenzo-[b,f]azepin-5-carboxamid-bzw. 10-Alkylthio-10,11-dihydro-5H-dibenzo [b,f]azepin-5-carboxamid-Derivaten vorgestellt. Synthesis of Sulfur-Containing Carbamazepine Derivatives Syntheses of derivatives of 10-alkylthio-5H-dibenzo[b,f]azepine-5-carboxamide and 10-alkylthio-10,11-dihydro-5H-dibenzo[b,f]azepine-5-carboxamide are described.

Die Bildung von Diathylnitrosamin durch Einwirkung von Nitrit auf Amfepramon unter magenahnlichen Bedingungen wird gc und dc verfolgt. Formation of Nitrosamines from Drugs, II: Reaction of Nitrite with Amfepramone Formation of diethylnitrosamine by the reaction of nitrite with amfepramone under conditions, as they normally prevail in the stomach, is observed by GC and TLC.

Die Titelverbindungen 4 lassen sich aus 5-Amino-3-methylpyrazolo[1,5-a]pyrid-7(4H)-on (2) und Keton-Mannichbasen oder Dehydro-Keton-Mannichbasen darstellen. Heterocycles via Mannich Bases, VII: Synthesis of Pyrazolo[1,5-a]pyrido[2,3-d]pyrimidin-9(4H)-ones The title compounds 4 are synthesised from 5-amino-3-methylpyrazolo[1,5-a]pyrimidin-7(4H)-one (2) and ketone Mannich bases or dehydro Mannich bases.

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.

Es werden zwei Verfahren zur Umlagerung von Epoxycarbamazepin (1) zu den 9,10-Dihydroacridinthioacetalen 3 und 4 bzw. ein Verfahren zur Darstellung eines O,S-Acetals 5 beschrieben. Anschliesend wird uber die Oxidation zu den Sulfoxiden 8 und 9 und den Sulfonen 10 und 11 berichtet. Rearrangement of 10,11-Epoxycarbamazepine to Sulfur-Containing Acridine Derivatives Two procedures are described for the rearrangement of epoxycarbamazepine (1) to the 9,10-dihydroacridinethioacetals 3 and 4. Furthermore a procedure is reported that leads to the O,S-acetal 5. Syntheses of the sulfoxides 8, 9 and of the sulfones 10, 11 are described.

Durch Kondensation von Aryl-alkyl-keton-Mannichbasen mit dem primaren Enamin des Acetylacetons entstehen 3-Acetylpyridine. Die Kondensation mit den Enaminen des Dihydroresorcins und des Dimedons fuhrt zu 1,4,5,6,7,8-Hexahydrochinolin-5-onen, die leicht zu 5,6,7,8-Tetrahydrochinolin-5-onen dehydriert werden. Synthesis of Pharmacologically Active Heterocyclic Compounds via Mannich Reaction, I. 3-Acetylpyridines and Hydroquinolines 3-Acetylpyridines are obtained by condensation of ketone Mannich bases with the enamine of acetylacetone. 1.4.5.6.7.8-Hexahydroquinolin-5-ones and 5.6.7.8-tetrahydroquinolin-5-ones are obtained by condensation of ketone Mannich bases with the enamines of dihydroresorcinol or dimedone and subsequent dehydrogenation.

The effect of several series of compounds on the biosynthesis of leukotriene B4 in human polymorphonuclear granulocytes (PMNL) was measured after stimulation of the cells by the Ca2+ ionophore A23187. Phenylhydrazone derivatives and some pyrrole derivatives strongly inhibited 5-lipoxygenase activity at 10 µM. In contrast, 4-aminopyrrolopyrimidines and 4-oxopyrrolopyrimidmes did not exhibit any effect. The compounds examined for inhibition of 5-lipoxygenase were also tested in a chemiluminescence assay for potential effects on the emission of photons as a measure of activated oxygen species generated by the stimulated granulocytes. There was a good correlation between lipoxygenase inhibition and suppression of chemiluminescence; however, some derivatives with no inhibitory activity against lipoxygenase still reduced chemiluminescence, which suggests that an alternative inhibitory mechanism of chemiluminescence must be present. Cyclooxygenase inhibitors such as aspirin did not suppress chemiluminescence of granulocytes. It is, therefore, unlikely that cyclooxygenase is required in the chemiluminescence reaction. In contrast, LTB4 seems to play an important role in the zymosan-induced chemiluminescence of PMNL.

Das bei der Umsetzung von 2-Methoxyanilin mit Ninhydrin entstehende, farbige Ketimin 1 wird durch NaBH4-Reduktion in die 3 moglichen, stereomeren 2-Amino-indan-1,3-diole uberfuhrt, womit seine Struktur bewiesen ist. Investigation of the Ninhydrin-Reaction The structure of the coloured ketimine 1, obtained by reaction of 2-methoxyaniline with ninhydrin, is determined by NaBH4-reduction to the three stereoisomeric 2-aminoindan-1,3-diols.

Die Kondensation von 5-Chlor-2-amino-benzhydrylamin mit o-Ameisensaure- oder o-Essigsaureestern fuhrt zu 3,4-Dihydrochinazolinen. Mit Oxalylchlorid entsteht ein Tetraaza-cyclo-tetradecan, mit Quadratsaureester ein tricyclisches Benzo-1,4-diazepin-Derivat. Synthesis of Heterocyclic Compounds by Condensation of 5-Chloro-2-amino-benzhydrylamine with C1 – C2 – Reagents. Condensation of 5-chloro-2-amino-benzhydrylamine with o-formic acid esters or o-acetic acid esters leads to 3,4-dihydroquinazolines; with oxalic acid chloride a tetraaza-cyclo-tetradecane, with squaric ester a tricyclic benzo-1,4-diazepin compound are obtained.

Es wird uber eine einfache Synthese fur Pyrrolo[2,3-d]pyrimidine berichtet, die von 2-Amino-3-cyanopyrrolen ausgeht und in guten bis sehr guten Ausbeuten zum Ziel fuhrt. Synthesis of Pyrrolo[2,3-d]pyrimidines A simple synthesis of pyrrolo[2,3-d]pyrimidines is described. Basic materials are 2-amino-3-cyano-pyrroles. The yields are good or excellent.

Es wird untersucht, wie weit das Prinzip der erstmals 1970 beobachteten Photocyclisierung von 3-Aminopropiophenonen zu 2-Aminocyclopropanolen1,2) auch auf die Bildung von Vierring-systemen ubertragbar ist. Es wird gezeigt, das die Cyclisierungsrate von 4-Aminobutyrophenonen zu 2-Aminocyclobutanolen in erster Linie von der Substitution der Seitenkette und der Art des eingesetzten Amins abhangig ist. Photocyclisation of 4-Aminobutyrophenones to 2-Aminocyclobutanols The photocyclisation of 3-aminopropiophenones leads to 2-aminocyclopropanols1,2). The application of this reaction to 4-aminobutyrophenones was investigated. It is shown that the formation of 2-aminocyclobutanols depends on the substituents on the aliphatic chain and on the nature of the amine used as starting material.

3(5)-Aminopyrazol und Derivate reagieren mit dem bifunktionellen Imidsaureester 2 zu 5-Amino-pyrazolo[1,5-a]pyrimidin-7(4H)-onen 7. 13C-Daten der Titelverbindungen werden angegeben. Synthesis of 5-Aminopyrazolo[1,5-a]pyrimidine-7(4H)-ones 3(5)-Aminopyrazole and derivatives are reacted with the bifunctional imidate 2 to yield 5-aminopyrazolo[1,5-a]pyrimidine-7(4H)-ones 7. 13C NMR data of the title compounds are reported.

Verschiedene Synthesewege zu substituierten 4-Aminobutyrophenonen werden untersucht und diskutiert. Bei der Alkylierung enolisierbarer Phenylketone mit β-tert.-Aminoalkylhalogeniden entstehen O- und C-Alkylgemische, deren prozentuale Zusammensetzung mit Hilfe der 1H-NMR-Spektren ermittelt wird. Synthesis of Highly Substituted 4-Aminobutyrophenones A number of synthetic routes to substituted 4-aminobutyrophenones are discussed. Alkylation of enolising phenylketones with β-tert.-aminoalkylhalides leads to mixtures of O- and C-alkyl derivates. The composition of these mixtures was derived from their 1H-nmr spectra.

A new method for the determination of lipoxins with electrochemical detection after high-performance liquid chromatography is described. The half-wave potentials of lipoxin A 4 and lipoxin B 4 at a glassy carbon electrode and a mobile phase of methanol—water (65:35, v/v) and 1 m M trifluoroacetic acid was found to be +1.14 V versus an Ag/AgCl reference electrode. The use of trifluoroacetic acid instead of sulphuric acid and lithium perchlorate led to a background current of 6–8 nA at +1.20 V. The detection limits for both lipoxins, based on a signal-to-noise ratio of 3:1, were found to be 5–10 pg (15–30 fmol). The new method was applied to an extract of human polymorphonuclear granulocytes, preincubated with 15-hydroxyeicosatetraenoic acid and stimulated with Ca 2+ ionophore A23187.

In vorangegangenen Mitt. beschrieben wir Verfahren zur Darstellung von Phosphorsaure-phenylester- und Phosphorsaure-4-nitro-phenylester-N,N′-diamiden. In der vorliegenden Veroffentlichung wird die Synthese von Phosphorsaurealkylester-N,N'-diamiden aus Phosphorsaurealkylesterdichloriden und primaren Aminen geschildert. Phosphorodiamidates, III: Synthesis of Alkyl Phosphorodiamidates In previous papers we described procedures to synthesize phenyl and 4-nitrophenyl phosphorodiamidates. In this paper a procedure is described to synthesize N, N′ -disubstituted alkyl phosphorodiamidates from alkyl phosphorodichloridates and primary amines.

Es wird eine reproduzierbare Darstellungsmethode fur “Nitroacetamidin (2A)” beschrieben. Nach den spektroskopischen Daten liegt es in der Enaminform 2B vor und stellt das 2-Nitroethen-1,1-diamin dar. The Structure of Nitroacetamidine. A reproducible method for the synthesis of “nitroacetamidine (2A)” is described. According to spectral data, it exists in the enaminic form 2B and represents 2-nitroethene-1,1-diamine.