2085-90-7Relevant academic research and scientific papers
Selective mono addition of aryllithiums to dialdehydes by micromixing
Nagaki, Aiichiro,Yamashita, Hiroki,Takahashi, Yusuke,Ishiuchi, Satoshi,Imai, Keita,Yoshida, Jun-Ichi
supporting information, p. 71 - 73 (2018/01/26)
Micromixing enables highly selective mono addition of aryllithiums to dialdehydes. Because the unchanged formyl group in the products can be used for further transformations, the present approach serves as a powerful method for protecting-group-free synthesis.
Synthesis and 2D-QSAR studies of neolignan-based diaryl-tetrahydrofuran and -furan analogues with remarkable activity against Trypanosoma cruzi and assessment of the trypanothione reductase activity
Hartmann, Ana Paula,de Carvalho, Marcelo Rodrigues,Bernardes, Lilian Sibelle Campos,de Moraes, Milena Hoehr,de Melo, Eduardo Borges,Lopes, Carla Duque,Steindel, Mario,da Silva, Jo?o Santana,Carvalho, Ivone
, p. 187 - 199 (2017/09/20)
Two series of diaryl-tetrahydrofuran and -furan were synthesised and screened for anti-trypanosomal activity against trypomastigote and amastigote forms of Trypanosoma cruzi, the causative agent of Chagas disease. Based on evidence that modification of a natural product may result in a more effective drug than the natural product itself, and using known neolignan inhibitors veraguensin 1 and grandisin 2 as templates to synthesise simpler analogues, remarkable anti-trypanosomal activity and selectivity were found for 3,5-dimethoxylated diaryl-furan 5c and 2,4-dimethoxylated diaryl-tetrahydrofuran 4e analogues with EC50 0.01 μM and EC50 0.75 μM, respectively, the former being 260-fold more potent than veraguensin 1 and 150-fold better than benznidazole, the current available drugs for Chagas disease treatment. The ability of the most potent anti-trypanosomal compounds to penetrate LLC-MK2 cells infected with T. cruzi amastigotes parasite was tested, which revealed 4e and 5e analogues as the most effective, causing no damage to mammalian cells. In particular, the majority of the derivatives were non-toxic against mice spleen cells. 2D-QSAR studies show the rigid central core and the position of dimethoxy-aryl substituents dramatically affect the anti-trypanosomal activity. The mode of action of the most active anti-trypanosomal derivatives was investigated by exploring the anti-oxidant functions of Trypanothione reductase (TR). As a result, diarylfuran series displayed the strongest inhibition, highlighting compounds 5d-e (IC50 19.2 and 17.7 μM) and 5f-g (IC50 8.9 and 7.4 μM), respectively, with similar or 2-fold higher than the reference inhibitor clomipramine (IC50 15.2 μM).
Arene-promoted lithiation of 1,n-dihaloalkanes (n=2-6): a comparative study
Abou, Abdeslam,Foubelo, Francisco,Yus, Miguel
, p. 10417 - 10424 (2007/10/03)
The reaction of 1,n-dichloroalkanes 3a (n=2-6) with an excess of lithium powder and a catalytic amount of 4,4′-di-tert-butylbiphenyl (DTBB; 2.5 mol %) in the presence of different carbonyl compounds [ButCHO, PhCHO, Et2CO, (CH2/
Transformation of zirconocene-olefin complexes into zirconocene allyl hydride and their use as dual nucleophilic reagents: Reactions with acid chloride and 1,4-diketone
Fujita, Kazuya,Yorimitsu, Hideki,Shinokubo, Hiroshi,Oshima, Koichiro
, p. 6776 - 6783 (2007/10/03)
Zirconocene-olefin complexes Cp2Zr(H2C=CHR), prepared in benzene-THF at 0 °C, react with acid chlorides to provide homoallylic alcohols. The key is an equilibrium between the zirconocene-olefin complexes and the corresponding zircono
Highly diastereoselective tandem reduction-allylation reactions of 1,4-diketones with zirconocene-olefin complexes
Fujita, Kazuya,Shinokubo, Hiroshi,Oshima, Koichiro
, p. 2550 - 2552 (2007/10/03)
Terminal alkenes act as dual nucleophiles in a zirconocene-mediated, highly 1,4-diastereoselective, tandem reduction-allylation reaction of 1,4-diketones. A zirconocene-alkene complex (in equilibrium with an allyl-zirconocene-hydride species) can deliver both hydride and an allyl group to a diketone, with control of the relative configuration of up three new stereogenic centers (see scheme).
Stereoselective Synthesis of anti-1,4-Diols by a BH3· THF-Mediated Rearrangement of 1,2-Disubstituted Cyclobutenes
Knapp, Kolja M.,Goldfuss, Bernd,Knochel, Paul
, p. 5259 - 5265 (2007/10/03)
A new stereoselective rearrangement of cyclobutylboranes, obtained by the hydroboration of 1,2-disubstituted cyclobutenes, provides anti-1,4-diols with good-to-excellent diastereoselectivity. The mechanism of the rearrangement is discussed based on theoretical calculations.
Facile reduction of aromatic aldehydes, ketones, diketones and oxo aldehydes to alcohols by an aqueous TiCl3/NH3 system: Selectivity and scope
Clerici, Angelo,Pastori, Nadia,Porta, Ombretta
, p. 3326 - 3335 (2007/10/03)
A simple and rapid procedure for the almost quantitative reduction of aromatic aldehydes, ketones, diketones and oxo aldehydes to alcohols by use of TiCl3/NH3 in aqueous methanol solution is reported. The reducing system distinguishes between different classes of aldehydes and/or ketones, and many functionalities that usually do not survive under reducing conditions are tolerated well. The concept of reversal of chemoselectivity has also been developed. A mechanism based on two sequential one-electron transfers from TiIII to the carbonyl carbon atom is proposed, the second SET becoming operative only in the presence of ammonium ion (either added or formed in situ). Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
Functionalized organolithium compounds of DTBB-catalyzed sulfur-lithium exchange
Foubelo, Francisco,Gutiérrez, Ana,Yus, Miguel
, p. 503 - 514 (2007/10/03)
The successive reaction of β- or γ-hydroxy or amino phenyl thioethers (1,4) with butyllithium and an excess of lithium powder in the presence of a catalytic amount of DTBB in THF at - 78°C leads to the formation of the corresponding β- or γ-functionalized organolithium compounds 2 or 5, respectively, which by treatment with different electrophiles [D2O, t- BuCHO, PhCHO, Me2CO, (CH2)4CO, (CH2)5CO] at temperatures ranging between - 78°C and room temperature yields, after hydrolysis with water, the expected functionalized alcohols or amines 3 or 6, respectively, in a completely regioselective manner.
Enantioselective Synthesis of C2-Symmetric Diols
Quallich, George J.,Keavey, Kenneth N.,Woodall, Teresa M.
, p. 4729 - 4732 (2007/10/02)
Catalytic reduction of diketones with erythro diphenyl oxazaborolidine yielded C2-symmetric diols in high enantiomeric excess.Enantiomeric excess increased and less meso isomer was generated when borane was employed equimolar with repect to the carbonyl groups and when stoichiometric oxazaborolidine was used.
Nucleophilic Attack on a Carbonyl Group Conjugated to a Chiral Centre: A Search For a Vinylogous Cram's Rule
Fleming, Ian,Kuehne, Hardy,Takai, Ken
, p. 725 - 728 (2007/10/02)
In a search for a vinylogous version of Cram's rule, 1,4-diphenylbut-2-ene-1,4-dione (5), 4-methoxy-1,4-diphenylbut-2-en-1-one (9), and hex-3-ene-2,5-dione (13) are found to be reduced with low or negligible diastereoselectivity.Similarly, the phenyl Grignard reagent showed no diastereoselectivity in its reaction with 4-methoxy-4-phenylbut-2-enal (12)
