- Microwave alkylation of lithium tetrazolate
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Abstract: N1-substituted tetrazoles are interesting ligands in transition metal coordination chemistry, especially in the field of spin crossover. Their synthesis is performed in most cases according to the Franke-synthesis, using a primary amine as reagent introducing the substitution pattern. To enhance flexibility in means of substrate scope, we developed a new protocol based on alkylation of lithium tetrazolate with alkyl bromides. The N1–N2 isomerism of the tetrazole during the alkylation was successfully suppressed by use of highly pure lithium tetrazolate and 30?vol.% aqueous ethanol as solvent, leading to pure N1-substituted products. The feasibility of this reaction was demonstrated by a selection of different substrates. Graphical abstract: [Figure not available: see fulltext.]
- Müller, Danny,Knoll, Christian,Weinberger, Peter
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- Spectroscopic, structural and magnetic investigations of iron(II) complexes based on 1-isopropyl- and 1-isobutyl-substituted tetrazole ligands
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Two partly new [Fe(intz)6](BF4)2 complexes with n = 3 and 4 (i3tz = 1-isopropyl-1H-tetrazole, i4tz = 1-isobutyl-1H- tetrazole) were synthesized and characterised by X-ray powder diffraction, magnetic susceptibility measurements, vibrational, electronic and 57Fe-M??bauer spectroscopy as well as DSC. The [Fe(i3tz)6](BF4)2 complex was re-investigated and shows an incomplete spin transition at Tc ~ 109 K, while the [Fe(i4tz)6](BF4)2 features a complete but rather gradual spin transition with T1/2 = 223 K. In the lack of suitable crystals of [Fe(intz)6](BF4)2 with n = 3 and 4, we synthesized crystals of [Ni(intz)6](BF4) 2 with n = 3 and 4, determined their X-ray crystal structures, and proved them to be homeotypic with the respective Fe-complexes by X-ray powder diffraction. DSC measurements showed an endothermic peak for the [Fe(i3tz) 6](BF4)2 around T = 260 K not corresponding to a spin transition and suggesting a structural phase transition at this temperature. A well-developed peak at Tp = 225 K matches the spin-transition temperature T1/2 = 223 K for [Fe(i4tz) 6](BF4)2.
- Hassan, Nader,Stelzl, Julia,Weinberger, Peter,Molnar, Gabor,Bousseksou, Azzedine,Kubel, Frank,Mereiter, Kurt,Boca, Roman,Linert, Wolfgang
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- APOPTOSIS SIGNAL-REGULATING KINASE 1 INHIBITORS AND METHODS OF USE THEREOF
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The present invention discloses compounds of Formula (I), or pharmaceutically acceptable salts, ester, stereoisomer, tautomer, solvate, hydrate, or combination thereof: which inhibit the Apoptosis signal-regulating kinase 1 (ASK-1), which associated with autoimmune disorders, neurodegenerative disorders, inflammatory diseases, chronic kidney disease, cardiovascular disease. The present invention further relates to pharmaceutical compositions comprising the aforementioned compounds for administration to a subject suffering from ASK-1 related disease. The invention also relates to methods of treating an ASK-1 related disease in a subject by administering a pharmaceutical composition comprising the compounds of the present invention. The present invention specifically relates to methods of treating ASK-1 associated with hepatic steatosis, including non-alcoholic fatty liver disease (NAFLD) and non-alcohol steatohepatitis disease (NASH).
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Page/Page column 48
(2018/12/02)
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- REACTIONS OF TRIMETHYLSILYL AZIDE WITH ALDEHYDES: FACILE AND CONVENIENT SYNTHESES OF DIAZIDES, TETRAZOLES, AND NITRILES
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The reactions of trimethylsilyl azide (TMSA) with various aldehydes were found to be versatile procedures for the synthesis of gem- and 1,3-diazides, tetrazoles, and nitriles, whose formation was varied by controlling the quantities of TMSA, catalyst, and the reaction conditions.
- Nishiyama, Kozaburo,Oba, Makoto,Watanabe, Akio
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p. 693 - 700
(2007/10/02)
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