1430733-96-2Relevant academic research and scientific papers
Cupin Variants as a Macromolecular Ligand Library for Stereoselective Michael Addition of Nitroalkanes
Fujieda, Nobutaka,Ichihashi, Haruna,Itoh, Shinobu,Kurisu, Genji,Nishikawa, Yosuke,Yuasa, Miho
, p. 7717 - 7720 (2020)
Cupin superfamily proteins (TM1459) work as a macromolecular ligand framework with a double-stranded β-barrel structure ligating to a Cu ion through histidine side chains. Variegating the first coordination sphere of TM1459 revealed that H52A and H54A/H58A mutants effectively catalyzed the diastereo- and enantioselective Michael addition reaction of nitroalkanes to an α,β-unsaturated ketone. Moreover, calculated substrate docking signified C106N and F104W single-point mutations, which inverted the diastereoselectivity of H52A and further improved the stereoselectivity of H54A/H58A, respectively.
Enantioselective Conjugate Addition of 2-Acetyl Azaarenes to β,β-Disubstituted Nitroalkene for the Construction of All-Carbon Quaternary Stereocenters
Ma, Hongli,Xie, Lei,Zhang, Zhenhua,Wu, Lin-Gang,Fu, Bin,Qin, Zhaohai
, p. 7353 - 7362 (2017)
The first highly enantioselective conjugate addition of 2-acetyl azaarenes to α-substituted-β-nitroacrylates was successfully realized under mild conditions by a Ni(II)-bisoxazoline complex, providing the desired adducts bearing an all-carbon quaternary stereocenter in high yield with excellent enantioselectivity. The products obtained in this system could be readily converted into optically active β2,2-amino esters, succinates, lactones, and lactams.
Solvent-free enantioselective conjugate addition and bioactivities of nitromethane to Chalcone containing pyridine
Zhang, Guoping,Zhu, Chun,Liu, Dengyue,Pan, Jianke,Zhang, Jian,Hu, Deyu,Song, Baoan
, p. 129 - 136 (2016/12/23)
A series of chiral thioureas derived from quinine were tested as catalysts in the enantioselective Michael additions of nitromethane to α,β-unsaturated ketones containing pyridine. The best results were obtained with the bifunctional catalyst prepared from 3,5-di(trifluoromethyl)-aniline under solvent-free conditions. This thiourea promoted the reaction with high enantioselectivities and chemical yields for aryl ketones. The origins of enantioselectivity were further investigated via experiment and computation. Meanwhile, the products from our reaction showed potent antibacterial activities against rice bacterial leaf blight, with the S-enantiomer performing much better than the R-enantiomer. Given the promising bioactivity of this class of molecules, our work is expected to offer important applications in developing future generations for drug design.
Enantioselective addition of aryl ketones and acetone to nitroalkenes organocatalyzed by carbamate-monoprotected cyclohexa-1,2-diamines
Flores-Ferrndiz, Jess,Stiven, Alexander,Sotorros, Lia,Gmez-Bengoa, Enrique,Chinchilla, Rafael
, p. 970 - 979 (2015/09/01)
Enantiomerically pure carbamate-monoprotected trans-cyclohexane-1,2-diamines are used as chiral organocatalysts for the addition of aryl ketones and acetone to nitroalkenes to give enantioenriched β-substituted γ-nitroketones. The reaction was performed i
Enantioselective LaIII-pyBOX-catalyzed nitro-michael addition to (E)-2-azachalcones
Blay, Gonzalo,Incerti, Celia,Munoz, M. Carmen,Pedro, Jose R.
, p. 1696 - 1705 (2013/04/10)
A [La(OTf)3] complex with a new pyBOX ligand bearing a bulky 1-naphthylmethyl substituent at the 4′-position of the oxazoline ring catalyzes the conjugate addition of nitroalkanes to a broad range of (E)-2-azachalcones, providing the expected nitro-Michael products with good yields and enantiomeric excesses up to 87 %. The optical purity of the products can be increased by a single crystallization. A plausible stereochemical model to account for the observed stereochemistry has been proposed. Conjugate addition of nitroalkanes to (E)-2-azachalcones is catalyzed by La III-pyBOX complexes to give nitro-Michael products with good yields and enantiomeric excesses up to 87 %. Some products can be obtained almost enantiopure by a single crystallization. The scope of the reaction is shown with 24 examples involving substituted 2-azachalcones and nitroalkanes. Copyright
