Search results for "medicinal"

Azomethin-imine durch Umsetzung von Diphenylketen mit Azodicarbonsäureestern

1981

Die Umsetzung von Diphenylketen mit Azodicarbonsaureester fuhrt zu den Azomethin-iminen 4, die 1,3-dipolare Reaktivitat zeigen: Addition von Diphenylketen liefert das Addukt 8, von Phenylisocyanat ergibt 7 und Dimerisierung fuhrt zu 5. Azomethine Imines by Reaction of Diphenylketene with Azodicarboxylates1) The reaction of diphenylketene with azodicarboxylates yields azomethine imines 4 which show 1,3-dipolaric reactivity: addition of diphenylketene yields the 2:1-adduct 8, addition of phenyl-isocyanate produces 7, and dimerization leads to 5.

Racemattrennung, Kristallstruktur und histaminartige Wirkung von 4-[1-(2-Aminoethylthio)ethyl]-5-methylimidazol

1983

Es wird die Racemattrennung von 4-[1-(2-Aminoethylthio)ethyl]-5-methylimidazol (1) mittels optisch aktiver Di-O-(p-toluoyl)weinsaure sowie die histaminartige Wirksamkeit der Enantiomeren beschrieben. Von (+)-1 · 2HCl · H2O wurde die Kristallstruktur bestimmt und bis zu einem R-Wert von 0.0483 verfeinert. Danach ist (+)-1R-konfiguriert. Von den beiden Enantiomeren besitzt nur (S)-(−)-1 H1-agonistische Aktivitat. Resolution, Crystal Structure, and Histamine-like Activity of 4-[1-(2-Aminoethylthio)ethyl]-5-methylimidazole The resolution of racemic 4-[1-(2-aminoethylthio)ethyl]-5-methylimidazole (1) using optically active Di-O-(P-toluoyl)tartaric acid as well as the histamine-like activity of t…

NMR study of the behaviour of some methoxynitrothiophenes toward sodium methoxide

1970

Influence of Reactant Polarity on the Course of the Inverse-Electron-Demand Diels−Alder Reaction. A DFT Study of Regio- and Stereoselectivity, Presen…

1999

The molecular mechanisms for the inverse-electron-demand Diels−Alder reactions between nitroethene and three substituted ethenes (propene, methyl vinyl ether, and dimethylvinylamine) to give the corresponding nitroso cycloadducts have been characterized with density functional theory methods using the B3LYP/6-31G* calculational level. On the basis of stability arguments and molecular orbital analysis relative rates, regioselectivity, and stereoselectivity, the presence of Lewis acid catalyst modeled by the BH3 system and the inclusion of solvent effects as a function of the nature of substituent in the dienophile fragment are analyzed and discussed. The ortho attack mode presents transition…

Antibakterielle wirkstoffe. VIII . Die aminomethinylierung in der reihe der aminothiazole

1982

Aus der die Umsetzung von 2-Amino-4-antipyrinyl-5-ethylthiazol (1) mit s-Triazin (2) und Pyrrolidin beinhaltenden Dreikomponentenreaktion geht das 4-Antipyrinyl-5-ethyl-2-[(4-pyrrolidinyl)methylenamino]thiazol (5) hervor. Struktur 5 last sich durch 1H- und 13C-NMR-Spektroskopie untermauern. The three-component reaction comprising the interaction of 2-amino-4-antipyrinyl-5-ethylthiazole (1) with s-triazine (2) and pyrrolidine leads to 4-anitpyrinyl-5-ethyl-2-[(4-pyrrolidinyl)methyleneamino]thiazole (5). Structure 5 is supported by 1H- and 13C-NMR spectroscopy.

Indoloquinolines, Indolobenzoxazines and Quinazolophthalazines Prepared from Norbornane/eneamino Acids and Hydrazides

2005

The reactions of di-endo- and di-exo-aminonorbornane/enecarboxylic acids 1–4 with ethyl 2-(2-oxocyclohexyl)acetate afforded methanoindoloquinolines 5, 6, 8, and 9, the oxo ester participating as a two-membered sp2 building block. In the cases of di-exo- and di-endo-aminonorbornenecarboxylic acids 2 and 4, methanoindolobenzoxazinediones 7 and 10 were also formed; compound 7 was also isolated from the mother liquor of 10. The reactions of ethyl 2-(2-oxocyclohexyl)acetate with aminonorbornane/enecarbohydrazides 11–14 result in the methanoquinazolophthalazines 15–18. The structures of the compounds were elucidated by NMR spectroscopy, and for 6, 7, 8, and 10 also by X-ray crystallography. (© Wi…

Partielle spezifische volumina von m.m′-ditolyl und seinen oligomeren

1969

Das partielle spezifische Volumen von m.m′-Ditolyl in Toluol wurde durch Dichtemessungen uber den gesamten Konzentrationsbereich bei 25°C bestimmt. Das hieraus berechnete molare Uberschusvolumen betragt −0,21 cm3/Mol bei einem Volumenbruch von 0,5. Die partiellen spezifischen Volumina von Oligomeren des m.m′-Ditolyls wurden in einem niedrigen Konzentrationsbereich in Toluol, Benzol und Trichlorathylen bei 25°C bestimmt. Sie sind in erster Naherung dem Molekulargewicht umgekehrt proportional. The partial specific volume of m.m′-ditolyl in toluene was determined by means of density measurement over the entire range of concentrations at 25°C. The molar excess volume computed hereof turns out t…

Preparative Polar Organometallic Chemistry. Vol. 1. VonL. Brandsma undH. D. Verkruijsse. Springer, Berlin 1987. 240 S., kartoniert, DM 78.00. – ISBN …

1989

2,2′-Dimethyl-2,2′-(m-phenyl­ene­dimethyl­ene)propane­dinitrile

2009

The title compound, C16H14N4, features an aromatic ring with two 2,2´-dicyanopropyl residues in positions 1 and 3, which are located above and below the ring plane. The two residues differ in their conformation with respect to the aromatic ring: whereas one of the Cmethyl-C-Cmethylene-Caromatic torsion angles is gauche [68.93 (12)°], the other one is fully staggered [177.63 (9)°]. The crystal structure is stabilized by C-H...N hydrogen-bonding interactions. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.037; wR factor = 0.101; data-to-parameter ratio = 15.0.

Crystal Engineering Studies of the Complexes of Ethyl Resorcinarene with Aromatic Nitrogen Heterocycles

2003

Five X-ray structures of complexes of ethyl resorcinarene with aromatic nitrogen heterocycles (imidazole, 1,2,4-triazole, pyridine, pyrazine, 2-pyridylmethanol and quinoline) show that ethyl resorcinarene spontaneously forms molecular inclusion complexes with five- and six-membered aromatic nitrogen heterocycles via π π and CH π interactions. However, with 10-membered quinoline, no molecular inclusion complex is formed. Instead, quinoline manifests crystal lattice inclusion.