844658-92-0Relevant academic research and scientific papers
Chiral, bridged bis(imidazolin-2-ylidene) complexes of palladium
Schneider, Sabine K.,Schwarz, Jürgen,Frey, Guido D.,Herdtweck, Eberhardt,Herrmann, Wolfgang A.
, p. 4560 - 4568 (2007)
Varieties of chiral, bridged bisimidazolium salts as well as the synthesis of palladium complexes of general formula [bridge {over(NC(H) {double bond, long} C(H)N (R*) C, -)}2 PdBr2] with the corresponding chelating N-heterocyclic carbene ligands is reported. This is the first systematic study of chiral bis(imidazolin-2-ylidene)palladium(II) complexes bearing chiral groups on the endocyclic nitrogens. Structural proof of such a chiral palladium(II) complex is presented by way of an X-ray diffraction study of complex 3a.
[3H metyrapol and 4-[131I]iodometomidate label overlapping, but not identical, binding sites on rat adrenal membranes
Berger, Michael L.,Hammerschmidt, Friedrich,Qian, Renzhe,Hahner, Stefanie,Schirbel, Andreas,Stichelberger, Martina,Schibli, Roger,Yu, Jie,Arion, Vladimir B.,Woschek, Anna,?hler, Elisabeth,Zolle, Ilse M.
, p. 1119 - 1130 (2013/08/25)
Metyrapone, metyrapol, and etomidate are competitive inhibitors of 11-deoxycorticosterone hydroxylation by 11β-hydroxylase. [ 3H]Metyrapol and 4-[131I]iodometomidate bind with high affinity to membranes prepared from bovine and rat adrenals. Here we report inhibitory potencies of several compounds structurally related to one or both of these adrenostatic drugs, against the binding of both radioligands to rat adrenal membranes. While derivatives of etomidate inhibited the binding of both radioligands with similar potencies, derivatives of metyrapone inhibited the binding of 4-[131I]iodometomidate about 10 times weaker than the binding of [3H]metyrapol. By X-ray structure analysis the absolute configuration of (+)-1-(2-fluorophenyl)-2-methyl-2-(pyridin-3-yl)-1-propanol [(+)-11, a derivative of metyrapol] was established as (R). We introduce 1-(2-fluorophenyl)-2-methyl-2-(pyridin-3-yl)-1-propanone (9; Ki = 6 nM), 2-(1-imidazolyl)-2-methyl-1-phenyl-1-propanone (13; 2 nM), and (R)-(+)-[1-(4-iodophenyl)ethyl]-1H-imidazole (34; 4 nM) as new high affinity ligands for the metyrapol binding site on 11β-hydroxylase and discuss our results in relation to a proposed active site model of 11β-hydroxylase.
Imidazolium-based chiral ionic liquids: Synthesis and application
Suzuki, Yumiko,Wakatsuki, Junichiro,Tsubaki, Mariko,Sato, Masayuki
, p. 9690 - 9700 (2013/10/22)
Synthesis of chiral ionic liquids containing an imidazole nucleus and chiral centers on N-substituents is reported. [(2S,3S)-2,3-Dihydroxybutane-1,4- bis(3-butylimidazolium)]-[bis(trifluoromethanesulfonyl)amide]2 and [(4S,5S)-2-phenyl-1,3-dioxo
Isoprene-mediated lithiation of 1-alkylimidazoles: Chiral induction of the alkyl substituent
Pastor, Isidro M.,Torregrosa, Rosario,Yus, Miguel
experimental part, p. 373 - 376 (2011/04/12)
The isoprene-mediated lithiation of imidazoles bearing a secondary alkyl substituent at the nitrogen (7, 8 and 13) and the subsequent nucleophilic addition to different electrophiles allows the preparation of the corresponding 2-functionalized imidazoles
Bridged imidazolium salts used as precursors for chelating carbene complexes of palladium in the Mizoroki-Heck reaction
Scherg, Tobias,Schneider, Sabine K.,Frey, Guido D.,Schwarz, Jürgen,Herdtweck, Eberhardt,Herrmann, Wolfgang A.
, p. 2894 - 2907 (2008/03/13)
A variety of chiral and achiral imidazolium salts is synthesized. Methylene-, ethylene-, propylene- and pyridinyl-bridged bis(imidazolium) halides are used to generate the respective free chelating carbenes. The synthesis of palladium complexes of general formula [cis-CH2{NC(H)=C(H)N(R)C} 2PdX2] with these chelating N-heterocyclic carbene ligands is reported. Structural proofs of complexes 28 and 46 are represented by X-ray diffraction studies. Catalytic applications in the Mizoroki-Heck reaction are presented. Georg Thieme Verlag Stuttgart.
Mitsunobu alkylation of imidazole: A convenient route to chiral ionic liquids
Kim, Eun Jin,Ko, Soo Y.,Dziadulewicz, Edward K.
, p. 631 - 633 (2007/10/03)
The Mitsunobu protocol offers a convenient route from imidazole to N-alkyl-substituted imidazoles, precursors to imidazolium-based ionic liquids, and is particularly useful for preparing chiral ionic liquids.
