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.
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.
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
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.
