70677-94-0Relevant academic research and scientific papers
Design, synthesis and X-ray crystallographic study of new nonsecosteroidal vitamin D receptor ligands
Demizu, Yosuke,Takahashi, Takeo,Kaneko, Fumiya,Sato, Yukiko,Okuda, Haruhiro,Ochiai, Eiji,Horie, Kyohei,Takagi, Ken-Ichiro,Kakuda, Shinji,Takimoto-Kamimura, Midori,Kurihara, Masaaki
scheme or table, p. 6104 - 6107 (2011/11/06)
We designed and synthesized nonsecosteroidal vitamin D receptor (VDR) ligands that formed H-bonds with six amino acid residues (Tyr143, Ser233, Arg270, Ser274, His301 and His393) of the VDR ligand-binding domain. The ligand YR335 exhibited potent transcriptional activity, which was comparable to those of 1α,25-dihydroxyvitamin D3 and YR301. The crystal structure of the complex formed between YR335 and the VDR ligand-binding domain was solved, which revealed that YR335 formed H-bonds with the six amino acid residues mentioned above.
Allyl sulfides are privileged substrates in aqueous cross-metathesis: Application to site-selective protein modification
Lin, Yuya A.,Chalker, Justin M.,Floyd, Nicola,Bernardes, Goncalo J. L.,Davis, Benjamin G.
supporting information; experimental part, p. 9642 - 9643 (2009/02/04)
Allyl sulfides undergo efficient cross-metathesis in aqueous media with Hoveyda-Grubbs second generation catalyst 1. The high reactivity of allyl sulfides in cross-metathesis was exploited in the first examples of cross-metathesis on a protein surface. S-Allylcysteine was incorporated chemically into the protein, providing the requisite allyl sulfide handle. Preliminary efforts to genetically incorporate S-allylcysteine into proteins are also reported. Copyright
Intramolecular Kulinkovich-de Meijere reactions of various disubstituted alkenes bearing amide groups
Madelaine, Claire,Ouhamou, Nouara,Chiaroni, Angèle,Vedrenne, Emeline,Grimaud, Laurence,Six, Yvan
, p. 8878 - 8898 (2008/12/21)
A range of amides fitted with (E) or (Z) disubstituted alkene groups were prepared and evaluated in intramolecular Kulinkovich-de Meijere reactions. The corresponding aminocyclopropanes were obtained with high diastereoselectivity. Good yields could be achieved with substrates bearing suitable substitutions at the olefin moieties.
Aza-cope rearrangement-Mannich cyclizations for the formation of complex tricyclic amines: Stereocontrolled total synthesis of (±)-gelsemine
Earley, William G.,Jacobsen, Jon E.,Madin, Andrew,Meier, G. Patrick,O'Donnell, Christopher J.,Oh, Taeboem,Old, David W.,Overman, Larry E.,Sharp, Matthew J.
, p. 18046 - 18053 (2007/10/03)
A detailed examination of the use of aza-Cope rearrangement-Mannich cyclization sequences for assembling the azatricyclo[4.4.0.02,8] decane core of gelsemine is described. Iminium ions and N-acyloxyiminium ions derived from endo-oriented 1-methoxy- or 1-hydroxybicyclo[2.2.2]oct-5-enylamines do not undergo the first step of this sequence, cationic aza-Cope rearrangement, to form cis-hydroisoquinolinium ions. However, the analogous base-promoted oxy-aza-Cope rearrangement does take place to form cis-hydroisoquinolones containing functionality that allows iminium ions or N-acyloxyiminium ions to be generated regioselectively in a subsequent step. Mannich cyclization of cis-hydroisoquinolones prepared in this way efficiently assembles the azatricyclo[4.4.0.02,8]decane unit of gelsemine. Using a sequential base-promoted oxy-aza-Cope rearrangement/Mannich cyclization sequence, gram quantities of azatricyclo[4.4.0.02,8]decanone 18, a central intermediate in our total of (±)-gelsemine, were prepared from 3-methylanisole in 12 steps and 16% overall yield.
An expeditious synthesis of pentosidine, an advanced glycation end product
Yokokawa, Fumiaki,Sugiyama, Hideyuki,Shioiri, Takayuki,Katagiri, Noriko,Oda, Osamu,Ogawa, Hiroshi
, p. 4759 - 4766 (2007/10/03)
The chemical synthesis of pentosidine (1), an advanced glycation end product, was achieved via the asymmetric alkylation of the chiral schiff base derived from (+)-2-hydroxy-3-pinanone ((+)-HyPN) and glycine tert-butyl ester, the mercury salt mediated intramolecular guanylation, and the regioselective alkylation of imidazo[4,5-b]pyridine ring. This reliable synthetic achievement will promise availability of pentosidine (1) in quantities.
Pentacoordinate organoaluminum chemistry: Catalytic efficiency of Me3Al in the epoxide cleavage with alkynyllithiums
Ooi,Kagoshima,Ichikawa,Maruoka
, p. 3328 - 3333 (2007/10/03)
A new and highly effective catalytic method for epoxide alkynylations has been developed that involves the chelation-controlled alkylation of heterosubstituted epoxides with Me3Al via pentacoordinate organoaluminum complexes by taking advantage of the exceedingly high affinity of aluminum to oxygen. For example, reaction of epoxy ether, (1-benzyloxy)-3-butene oxide (1), in toluene with PhC?CLi under the influence of catalytic Me3Al (10 mol%) proceeded smoothly at 0 °C for 5 h to furnish the alkynylation product, 1-(benzyloxy)-6-phenylhex-5-yn-3-ol, in 76% yield [cf. 3% without Me3Al catalyst; 78% with stoichiometric Me3Al under similar conditions]. This represents the first catalytic procedure for the amphiphilic alkylation of epoxides. The participation of pentacoordinate Me3Al complexes of epoxy ethers of type 1 is emphasized by comparing the reactivity with the corresponding simple epoxide, 5-phenyl-1-pentene oxide, which was not susceptible to nucleophile attack of PhC?CLi with catalytic Me3Al under similar conditions. The pentacoordinate complex formation of Me3Al with epoxy ether 1 is characterized by low-temperature 13C and 27Al NMR spectroscopy. This approach is also applicable to the selective alkynylation of tosyl aziridines with adjacent ether functionality, which provides a promising method for amino alcohol synthesis.
