Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 k...Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 known compounds were isolated from the liquid fermentation broth of endophytic Streptomyces sp.YINM00048 obtained from Agrimonia pilosa.Their structures were elucidated through comprehensive spectroscopic analysis,including nuclear magnetic resonance,high-resolution mass spectrometry,and single-crystal X-ray diffraction,supported by time-dependent density functional theory(TDDFT)-electronic circular dichroism(ECD)calculations.Furthermore,compound 2 displayed weak cytotoxic activity against A549 and SMMC-7721 cell lines with IC50 values of 62.69 and 55.07μmol/L,respectively.展开更多
The coordination chemistry of glutarimide-dioxime(H_(3)A)has been studied related to applications in uranyl sequestration from seawater and for the stabilization of early transition metals in high oxidation states.We ...The coordination chemistry of glutarimide-dioxime(H_(3)A)has been studied related to applications in uranyl sequestration from seawater and for the stabilization of early transition metals in high oxidation states.We report here that the H_(2)A−anion is also suitable for stabilizing Ce(IV)and acts as a tridentate ligand to form the[Ce(H_(2)A)_(3)]^(+)cation.The metal complexes[Ce(H_(2)A)_(3)]Cl and[Ce(H_(2)A)_(3)][BPh_(4)]have been obtained by oxidation of CeIII in the presence of H_(3)A under aerobic conditions.UV-Vis spectroscopy and DFT calculations were performed to characterize the electronic structure and ligand-to-metal charge transfer(LMCT)bands of[CeIV(H_(2)A)_(3)]^(+).X-ray absorption spectroscopy(XAS)was also performed to verify the Ce(IV)oxidation state.Absent a clear electrochemical signal for cerium reduction in[Ce(H_(2)A)_(3)]Cl or[Ce(H_(2)A)_(3)][BPh_(4)]under a range of conditions,DFT calculations predicted a Ce(III/IV)redox couple of−1.22 V vs.Fc/Fc^(+).These results further expand the coordination chemistry of glutarimide-dioxime to tetravalent cerium.展开更多
Five glutarimide alkaloids cordiarimide A （5）, cordiarimide B （6）, crotonimide A （3）, crotonimide B （4）, and julocrotine （2） have been synthesized starting from Boc-L-glutamine （7）. The benzylic alcohol ch...Five glutarimide alkaloids cordiarimide A （5）, cordiarimide B （6）, crotonimide A （3）, crotonimide B （4）, and julocrotine （2） have been synthesized starting from Boc-L-glutamine （7）. The benzylic alcohol chiral centre of cordiarimides B （6） has been established in 6 ： 1 diastereoselectivity by catalytic asymmetric hydrogenation using Zhou＇s catalytic system Pd（CF3CO2）2/（R,R）-Me-DuPhos.展开更多
文摘Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 known compounds were isolated from the liquid fermentation broth of endophytic Streptomyces sp.YINM00048 obtained from Agrimonia pilosa.Their structures were elucidated through comprehensive spectroscopic analysis,including nuclear magnetic resonance,high-resolution mass spectrometry,and single-crystal X-ray diffraction,supported by time-dependent density functional theory(TDDFT)-electronic circular dichroism(ECD)calculations.Furthermore,compound 2 displayed weak cytotoxic activity against A549 and SMMC-7721 cell lines with IC50 values of 62.69 and 55.07μmol/L,respectively.
基金support from the University of Pennsylvania and the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences,Separation Science program under Award DE-SC0017259National Laboratory was supported by the Director,Office of Science,Office of Basic EnergySciences,Division of Chemical Sciences,Geosciences,and Biosciences Heavy Element Chemistry Program of the U.S.Department of Energy(DOE)at LBNL under Contract No.DE-AC02-05CH11231+2 种基金XANES measurements were performed at beam-line 11-2 at the Stanford Synchrotron Radiation Lightsource,which is supported by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences under contract no.DE-AC02-76SF00515We also thank the U.S.Department of Energy,Office of Basic Energy Sciences under award DE-SC0020169 for partial support of E.Lthe Extreme Science and Engineering Discovery Environment(XSEDE),which is supported by NSF(ACI-1548562).
文摘The coordination chemistry of glutarimide-dioxime(H_(3)A)has been studied related to applications in uranyl sequestration from seawater and for the stabilization of early transition metals in high oxidation states.We report here that the H_(2)A−anion is also suitable for stabilizing Ce(IV)and acts as a tridentate ligand to form the[Ce(H_(2)A)_(3)]^(+)cation.The metal complexes[Ce(H_(2)A)_(3)]Cl and[Ce(H_(2)A)_(3)][BPh_(4)]have been obtained by oxidation of CeIII in the presence of H_(3)A under aerobic conditions.UV-Vis spectroscopy and DFT calculations were performed to characterize the electronic structure and ligand-to-metal charge transfer(LMCT)bands of[CeIV(H_(2)A)_(3)]^(+).X-ray absorption spectroscopy(XAS)was also performed to verify the Ce(IV)oxidation state.Absent a clear electrochemical signal for cerium reduction in[Ce(H_(2)A)_(3)]Cl or[Ce(H_(2)A)_(3)][BPh_(4)]under a range of conditions,DFT calculations predicted a Ce(III/IV)redox couple of−1.22 V vs.Fc/Fc^(+).These results further expand the coordination chemistry of glutarimide-dioxime to tetravalent cerium.
基金Project supported by the National Natural Science Foundation of China （No. 20832005） and the National Basic Research Program （973 Program） of China （No. 2010CB833200）.
文摘Five glutarimide alkaloids cordiarimide A （5）, cordiarimide B （6）, crotonimide A （3）, crotonimide B （4）, and julocrotine （2） have been synthesized starting from Boc-L-glutamine （7）. The benzylic alcohol chiral centre of cordiarimides B （6） has been established in 6 ： 1 diastereoselectivity by catalytic asymmetric hydrogenation using Zhou＇s catalytic system Pd（CF3CO2）2/（R,R）-Me-DuPhos.
