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The dihydropyran 3 reacts with sulfonyl azides to give the known (sulfonylimino)-ethers ( = lactone sul-fonylimines) 4 and 18 . Reaction of 4 with NH2NH2 · H2O leads to the aminoiriazole-dibulanol 5 , characterized as its tetraacetate 8 , and not, as previously claimed, to 6 or 7 . Similarly, the dihydrofuran-derived (tosylimino)-ether 10 yields 11 The structure of 5 was established by X-ray analysis, and a mechanism for its formation is proposed. Reaction of 4 with NH2NMe2 afforded the lactone hydrazone 16 and the hydrazidine 17. Catalysis by imidazole suppressed the formation of 17 similarly, the [(trifluoromethyl)sulfonyl]imine 18 yielded 16, and, by reaction with NH2N(Me)Ph or 4-amino-4H-1,2,4-triazole, the lactone hydrazone 19 and the adduct 20 , respectively. The 1,4-lactone hydrazone 21 was obtained from 10 or from 22 . The structure of 20 was established by X-ray analysis. Treatment of 16 with BuLi followed by BnBr yielded the α-alkylated lactone hydrazone 23 . 相似文献
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Studies are described on the metabolism and the toxicological analysis of the amphetamine-derived designer drug 2,5-dimethoxy-4-bromo-amphetamine (DOB) and its corresponding N-methyl analogue 2,5-dimethoxy-4-bromo-methamphetamine (MDOB) in rat urine using gas chromatographic/mass spectrometric techniques. The identified metabolites indicated that DOB was metabolized by O-demethylation followed by oxidative deamination to the corresponding ketone as well as deamination followed by reduction to the corresponding alcohol. Other metabolic pathways were O,O-bisdemethylation or hydroxylation of the side chain followed by O-demethylation and deamination to the corresponding alcohol. The expected oxo compound after deamination could not be detected. All metabolites carrying hydroxy groups were found to be partly excreted in the conjugated form. MDOB underwent O-demethylation, O,O-bisdemethylation, or hydroxylation of the side chain followed by O-demethylation. Additional N-demethylation to DOB occurred, including the above-mentioned metabolites. Again, all metabolites carrying hydroxy groups were found to be partly excreted in the conjugated form. The authors' systematic toxicological analysis (STA) procedure using full-scan GC/MS after acid hydrolysis, liquid-liquid extraction, and microwave-assisted acetylation allowed the detection of an intake of a dose of DOB and MDOB in rat urine that corresponds to a common drug user's dose. Assuming a similar metabolism, the described STA procedure in human urine should be suitable as proof of an intake of DOB and MDOB. 相似文献
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Heliana Cárdenas Fabian Frahsa Sebastian Fritschi Alexandre Nicolas Simon Papenkort Thomas Voigtmann Matthias Fuchs 《The European physical journal. Special topics》2017,226(14):3039-3060
We review recent progress on a microscopic theoretical approach to describe the nonlinear response of glass-forming colloidal dispersions under strong external forcing leading to homogeneous and inhomogeneous flow. Using mode-coupling theory (MCT), constitutive equations for the rheology of viscoelastic shear-thinning fluids are obtained. These are, in suitably simplified form, employed in continuum fluid dynamics, solved by a hybrid-Lattice Boltzmann (LB) algorithm that was developed to deal with long-lasting memory effects. The combined microscopic theoretical and mesoscopic numerical approach captures a number of phenomena far from equilibrium, including the yielding of metastable states, process-dependent mechanical properties, and inhomogeneous pressure-driven channel flow. 相似文献
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Meyer MR Dinger J Schwaninger AE Wissenbach DK Zapp J Fritschi G Maurer HH 《Analytical and bioanalytical chemistry》2012,402(3):1249-1255
The opioid 3-methylfentanyl, a designer drug of the fentanyl type, was scheduled by the Controlled Substance Act due to its
high potency and abuse potential. To overcome this regulation, isofentanyl, another designer fentanyl, was synthesized in
a clandestine laboratory and seized by the German police. The aims of the presented study were to identify the phase I and
phase II metabolites of 3-methylfentanyl and isofentanyl in rat urine, to identify the cytochrome P450 (CYP) isoenzymes involved
in their initial metabolic steps, and, finally, to test their detectability in urine. Using liquid chromatography (LC)–linear
ion trap–mass spectrometry (MSn), nine phase I and five phase II metabolites of 3-methylfentanyl and 11 phase I and four phase II metabolites of isofentanyl
could be identified. The following metabolic steps could be postulated for both drugs: N-dealkylation followed by hydroxylation
of the alkyl and aryl moiety, hydroxylation of the propanamide side chain followed by oxidation to the corresponding carboxylic
acid, and, finally, hydroxylation of the benzyl moiety followed by methylation. In addition, N-oxidation of isofentanyl could
also be observed. All hydroxy metabolites were partly excreted as glucuronides. Using recombinant human isoenzymes, CYP2C19,
CYP2D6, CYP3A4, and CYP3A5 were found to be involved in the initial metabolic steps. Our LC-MSn screening approach allowed the detection of 0.01 mg/L of 3-methylfentanyl and isofentanyl in spiked urine. However, in urine
of rats after the administration of suspected recreational doses, the parent drugs could not be detected, but their common
nor metabolite, which should therefore be the target for urine screening. 相似文献
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Sauer C Peters FT Staack RF Fritschi G Maurer HH 《Journal of mass spectrometry : JMS》2006,41(8):1014-1029
Studies are described on the metabolism and toxicological detection of the phencyclidine-derived designer drug N-(1-phenylcyclohexyl)-3-ethoxypropanamine (PCEPA) in rat urine using gas chromatographic/mass spectrometric techniques. The identified metabolites indicated that PCEPA was metabolized by N-dealkylation, O-deethylation partially followed by oxidation of the resulting alcohol to the corresponding carboxylic acid, hydroxylation of the cyclohexyl ring at different positions of PCEPA, N-dealkyl PCEPA, O-deethyl PCEPA, and of the corresponding carboxylic acids. Finally, aromatic hydroxylation of PCEPA, the corresponding carboxylic acids, and O-deethyl PCEPA, the latter partially followed by oxidation to the corresponding carboxylic acid and hydroxylation of the cyclohexyl ring could be observed. All metabolites were partially excreted in the conjugated form. The authors' systematic toxicological analysis (STA) procedure using full-scan GC/MS after acid hydrolysis, liquid-liquid extraction, and microwave-assisted acetylation allowed the detection in rat urine of an intake of a common drug users' dose of PCEPA. Assuming a similar metabolism in humans, the STA in human urine should be suitable as proof of intake of PCEPA. 相似文献