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

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.     

Characterization of a covalent triazine-humic acid conjugate by gas chromatography

The aim of the described method was the characterization of a “atrazine-mercaptopropionic acid” humic acid conjugate, which was required for the calibration of immunoassays to determine bound residues. In order to estimate the amount of bound triazine, an oxidative nucleophilic substitution reaction of the covalently linked “atrazine-mercaptopropionic acid” to a new triazine derivative “atrazine-methoxyethanol” was performed. This cleavage product was quantified by gas chromatography. The conditions for this cleavage procedure were optimized and applied to the “atrazine-mercaptopropionic acid” humic acid conjugate and to a humic acid blank. The amount of bound “atrazine-mercaptopropionic acid” was calculated to 16.6 ± 2.5 μmol triazine per gram humic acid, which is equivalent to 0.39 ± 0.07% atrazine. Received: 7 August 1997 / Accepted: 12 September 1997     

Tumorhemmende wirkstoffe, XIII [1] aromatisch carbocyclisch und heterocyclisch substituierte 2-perfluoralkylpyrimido[1,2-a]benzimidazole

The interaction of 2-aminobenzimidazole with the appropriate β-diketones carrying fluoroalkyl groupings has led to the 2-perfluoroalkylpyrimido[1,2-a]benzimidazoles as follows: 4-phenyl-, 4-(2'-naphthyl)-, 4-(3'-pyridyl)-, 4-(2'-furyl)-, and 4-(2,-thienyl)-2-trifluoromethylpyrimido[1,2-a]benzimidazole, and 4-(2'-thienyl)-2-(heptafluoropropylpyrimido [1,2-a]benzimidazole.     

Über die Sulfurierung von Thionaphthen und Methylthionaphthenen

Zusammenfassung Die Sulfurierung des Thionaphthens, des 2-Methyl-, 3-Methyl-, 5-Methyl- und des 2,3-Dimethylthionaphthens, die Herstellung der entsprechenden Sulfosäurechloride,-amide und-anilide, die Ermittlung der Stellung des Sulfosäurerestes am Thionaphthenringsystem und die Wiederabspaltung der SO₃H-Gruppe wird beschrieben.     

Dehydro-C-mannich-basen durch aminomethinylierung

By a three-component-reaction comprising the interaction of a CH-acidic compound with s-triazine (1) and a secondary amine, a new way leading to the structural class of dehydro-C-Mannich-bases is described. The dehydro-C-Mannich-bases 6a, 6b, 8a, 8b, 8c and 10 arise from the use of diethyl malonate (2), ethyl cyanoacetate (7a), ethyl acetoacetate (7c), and acetophenone (9) as CH-acidic compounds.     

Structure and Mechanism of an Aspartimide‐Dependent Peptide Ligase in Human Legumain

Peptide ligases expand the repertoire of genetically encoded protein architectures by synthesizing new peptide bonds, energetically driven by ATP or NTPs. Here, we report the discovery of a genuine ligase activity in human legumain (AEP) which has important roles in immunity and tumor progression that were believed to be due to its established cysteine protease activity. Defying dogma, the ligase reaction is independent of the catalytic cysteine but exploits an endogenous energy reservoir that results from the conversion of a conserved aspartate to a metastable aspartimide. Legumain’s dual protease–ligase activities are pH‐ and thus localization controlled, dominating at acidic and neutral pH, respectively. Their relevance includes reversible on–off switching of cystatin inhibitors and enzyme (in)activation, and may affect the generation of three‐dimensional MHC epitopes. The aspartate–aspartimide (succinimide) pair represents a new paradigm of coupling endergonic reactions in ATP‐scarce environments.     

Antidiabetische wirkstoffe. V Lang- und verzweigtkettig substituierte chlor-dihexylamino-1,3,5-triazine

The nucleophilic substitution of one chlorine atom in 2,4-dichloro-6-dihexylamino-1,3,5-triazine ( 1 ) by amines 2a-c leads to the alkylamino-chlorodihexylamino-1,3,5-triazines 3a-c . Typical signals in the ¹H-nmr spectra of structure type 3 are the triplet at 0.9 ppm for the terminal methyl groups and the multiplet at 3.3–3.65 ppm for the methylene groups neighboring the nitrogen atoms. Compound class 3 comprises representatives exhibiting antidiabetic, trichomonacidal, antiviral and anthelminthic activity.