Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for t...Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for the two drugs were performed and confirmed by theevidence of J_(HF) and J_(CF). Conclusion The structures of amlodipine and risperidone wereconfirmed by careful analysis of regular 1D and 2D NMR spectroscopy.展开更多
Bile acids are the main body of enterohepatic circulation in vivo.They have essential functions such as emulsifying fat,bacteriostasis and regulating multiple metabolic pathways as signal molecules.However,the assignm...Bile acids are the main body of enterohepatic circulation in vivo.They have essential functions such as emulsifying fat,bacteriostasis and regulating multiple metabolic pathways as signal molecules.However,the assignments of NMR signals for some lowconcentration bile acids are still needed.This study combined 1D nuclear magnetic resonance(NMR)and 2D NMR techniques including 1He1H correlation spectroscopy(COSY),1He1H total correlation spectroscopy(TOCSY),1H J-resolved spectroscopy(J-Res),1He13C heteronuclear single quantum coherence spectroscopy(HSQC),and 1He13C heteronuclear multiple bond correlation spectroscopy(HMBC)to assign the 1H and 13C signals of six bile acids in aqueous solution at physiological pH(~7.4)and nine bile acids in methanol.These data are of importance to the NMR-based studies on lipid digestion,absorption,and metabolism.展开更多
Aim To investigate the structure of mogroside Ⅳa isolated from traditionalChinese medicine fructus mo-mordicae [fruits of Siraitia grosvenori (Swingle) C. Jeffery] andsummarize the NMR characteristics of the structur...Aim To investigate the structure of mogroside Ⅳa isolated from traditionalChinese medicine fructus mo-mordicae [fruits of Siraitia grosvenori (Swingle) C. Jeffery] andsummarize the NMR characteristics of the structure. Methods Common extraction, separation andpurification methods were used. Various NMR techniques including ~1H NMR, ^(13)C NMR, DEPT, ~1H-~1HCOSY, HSQC, HMBC, NOESY and molecular model simulated by computer were used to elucidate thestructure. Results ~1H and ^(13)C NMR signals of mogroside Ⅳa were assigned, and spectroscopicbasis was obtained for identification of such type of compounds. Conclusion 1D and 2D NMR techniquesincluding ~1H-~1H COSY, HSQC, HMBC, NOESY spectra are powerful tools for structure analysis. Thestructure determined by NMR methods is identical with energy minimized conformation simulated bycomputer.展开更多
The sequence structures of emulsion-processed SBR and solution-processed (by lithium catalyst) SBR were investigated by ^(13)C-NMR spectroscopy. Seventeen peaks within unsaturated carbon region were recorded under the...The sequence structures of emulsion-processed SBR and solution-processed (by lithium catalyst) SBR were investigated by ^(13)C-NMR spectroscopy. Seventeen peaks within unsaturated carbon region were recorded under the adopted experimental conditions. Assignments for these peaks were made by empirical-parameter-evaluation method.展开更多
The WRKY proteins are a family of plant-specific transcription factors(TFs)that are widely involved in plant development and anti-stress responses.Arabidopsis WRKY11(AtWRKY11)functions in regulating plant defense agai...The WRKY proteins are a family of plant-specific transcription factors(TFs)that are widely involved in plant development and anti-stress responses.Arabidopsis WRKY11(AtWRKY11)functions in regulating plant defense against abiotic stress and belongs to the Ild subgroup of WRKY TFs.We herein report the expres sion,purification and preliminary structural characterization of AtWRKY11 DNA-binding domain(DBD)using solution NMR Almost complete backbone chemical shift assignments of AtWRKY11-DBD have been ob-tained.Chemical shift-based secondary structure analysis suggests that AtWRKY11-DBD may exhibit local conformational diferences from the X-ray structure of the C-terminal WRKY domain of AtWRKY1,particularly in the β1 and β5 strands.Our current study provides the basis for further structural and interactional studies.展开更多
Phthalate acid esters （PAEs） possess endocrine disruptive effects and can produce reproductive and developmental toxicities. In this paper, both experimental and theoretical studies on FT-IR, Raman and 1H NMR spectr...Phthalate acid esters （PAEs） possess endocrine disruptive effects and can produce reproductive and developmental toxicities. In this paper, both experimental and theoretical studies on FT-IR, Raman and 1H NMR spectra of diethyl phthalate （DEP） have been carried out. The geometrical structure of DEP was optimized at the HF/6-31G＊, HF/6-311G＊＊, B3LYP/6-31G＊, and B3LYP/6-31 IG＊＊ levels, respectively. The harmonic vibrational frequencies, IR intensity, Raman activity and 1H NMR chemical shifts have been computed at the B3LYP/6-31G＊ and B3LYP/6-311G＊＊ levels. Anharmonic corrections to frequencies were obtained by means of second-order perturbation theory （PT2） at the B3LYP/6-31G＊ level. Based on potential energy distribution （PED）, the vibrational assignments have also been performed. The theoretical calculation values were compared with the experimental observations and the results indicate they are in excellent agreement.展开更多
The study on ^(13)C-NMR spectra of aliphatic carbon region of emuision-processed and solution-processed (by lithium catalyst) SBR was carried out. The assignments for more than thirty odd peaks observed experimentally...The study on ^(13)C-NMR spectra of aliphatic carbon region of emuision-processed and solution-processed (by lithium catalyst) SBR was carried out. The assignments for more than thirty odd peaks observed experimentally were made by using 'corresponding analysis' method, combined with the empirical parameters reported in literature. The peak intensifies were calculated based on BemouUian statistic assumption.展开更多
An approach for distinguishing two types of positional isomers of dimeric shikonin and its analogs was explored with ^(4)JC,H long-range correlation by prolonging the acquisition time at ^(2,3)JC,H values of 2.0 and 8...An approach for distinguishing two types of positional isomers of dimeric shikonin and its analogs was explored with ^(4)JC,H long-range correlation by prolonging the acquisition time at ^(2,3)JC,H values of 2.0 and 8.0Hz.Furthermore,the ^(1)H(proton)nuclear magnetic resonance(NMR)pattern of phenolic hydroxyl protons was developed as a“diagnosis signal”to ascertain the relative location of each side chain in DMSO-d_(6) at sample concentrations of 0.022-0.034 mol/L.The chemical shift differences of 0.6ppm between OH-5' and OH-1 and between OH-8'and OH-4 are assigned to Type A and Type B,respectively.All reported ambiguous structures were corrected by this pattern.Additionally,the steric structures of isolated compounds were elucidated by quantum chemical calculations of electronic circular dichroism(ECD)spectra.展开更多
Nuclear magnetic resonance(NMR)spectroscopy is an indispensable tool to probe weak protein-ligand interactions,which are key to the hit identification and hit-to-lead evolution in fragment-based drug discovery(FBDD).T...Nuclear magnetic resonance(NMR)spectroscopy is an indispensable tool to probe weak protein-ligand interactions,which are key to the hit identification and hit-to-lead evolution in fragment-based drug discovery(FBDD).The integration of NMR technology in FBDD has facilitated the development of a diverse array of candidate compounds and FDAapproved drugs.Here,we summarized the rapid advancement and application of NMR techniques in contemporary China,which serves as a catalyst for the ongoing prosperousness of fragment-derived inhibitors against various targets.展开更多
WITHDRAWAL:Zhang,J.J.,Guo,Y.Q.,Qin,Z.Y.,Wei,C.T.,Hu,Q.H.,Vandeginste,V.,Miao,H.Y.,Yao,P.,and Zhang,P.F.,“Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphol...WITHDRAWAL:Zhang,J.J.,Guo,Y.Q.,Qin,Z.Y.,Wei,C.T.,Hu,Q.H.,Vandeginste,V.,Miao,H.Y.,Yao,P.,and Zhang,P.F.,“Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphological Division and Fractal Models”,Acta Geologica Sinica-English Edition(Accepted Article):https://doi.org/10.1111/1755-6724.15094.展开更多
文摘Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for the two drugs were performed and confirmed by theevidence of J_(HF) and J_(CF). Conclusion The structures of amlodipine and risperidone wereconfirmed by careful analysis of regular 1D and 2D NMR spectroscopy.
文摘Bile acids are the main body of enterohepatic circulation in vivo.They have essential functions such as emulsifying fat,bacteriostasis and regulating multiple metabolic pathways as signal molecules.However,the assignments of NMR signals for some lowconcentration bile acids are still needed.This study combined 1D nuclear magnetic resonance(NMR)and 2D NMR techniques including 1He1H correlation spectroscopy(COSY),1He1H total correlation spectroscopy(TOCSY),1H J-resolved spectroscopy(J-Res),1He13C heteronuclear single quantum coherence spectroscopy(HSQC),and 1He13C heteronuclear multiple bond correlation spectroscopy(HMBC)to assign the 1H and 13C signals of six bile acids in aqueous solution at physiological pH(~7.4)and nine bile acids in methanol.These data are of importance to the NMR-based studies on lipid digestion,absorption,and metabolism.
文摘Aim To investigate the structure of mogroside Ⅳa isolated from traditionalChinese medicine fructus mo-mordicae [fruits of Siraitia grosvenori (Swingle) C. Jeffery] andsummarize the NMR characteristics of the structure. Methods Common extraction, separation andpurification methods were used. Various NMR techniques including ~1H NMR, ^(13)C NMR, DEPT, ~1H-~1HCOSY, HSQC, HMBC, NOESY and molecular model simulated by computer were used to elucidate thestructure. Results ~1H and ^(13)C NMR signals of mogroside Ⅳa were assigned, and spectroscopicbasis was obtained for identification of such type of compounds. Conclusion 1D and 2D NMR techniquesincluding ~1H-~1H COSY, HSQC, HMBC, NOESY spectra are powerful tools for structure analysis. Thestructure determined by NMR methods is identical with energy minimized conformation simulated bycomputer.
文摘The sequence structures of emulsion-processed SBR and solution-processed (by lithium catalyst) SBR were investigated by ^(13)C-NMR spectroscopy. Seventeen peaks within unsaturated carbon region were recorded under the adopted experimental conditions. Assignments for these peaks were made by empirical-parameter-evaluation method.
基金This work was supported by grants 2018YFE0202300,2018YFA0704002 from the National Key R&D Program of Chinagrant 21735007 from the National Natural Science Foundation of China to M.L.grant 21991083 from the National Natural Science Foundation of China to Y.H.
文摘The WRKY proteins are a family of plant-specific transcription factors(TFs)that are widely involved in plant development and anti-stress responses.Arabidopsis WRKY11(AtWRKY11)functions in regulating plant defense against abiotic stress and belongs to the Ild subgroup of WRKY TFs.We herein report the expres sion,purification and preliminary structural characterization of AtWRKY11 DNA-binding domain(DBD)using solution NMR Almost complete backbone chemical shift assignments of AtWRKY11-DBD have been ob-tained.Chemical shift-based secondary structure analysis suggests that AtWRKY11-DBD may exhibit local conformational diferences from the X-ray structure of the C-terminal WRKY domain of AtWRKY1,particularly in the β1 and β5 strands.Our current study provides the basis for further structural and interactional studies.
基金Financially supported by the National Natural Science Foundation of China (41071319, 20977046)the Fundamental Research Funds for the Central Universities of China (1112021101)
文摘Phthalate acid esters （PAEs） possess endocrine disruptive effects and can produce reproductive and developmental toxicities. In this paper, both experimental and theoretical studies on FT-IR, Raman and 1H NMR spectra of diethyl phthalate （DEP） have been carried out. The geometrical structure of DEP was optimized at the HF/6-31G＊, HF/6-311G＊＊, B3LYP/6-31G＊, and B3LYP/6-31 IG＊＊ levels, respectively. The harmonic vibrational frequencies, IR intensity, Raman activity and 1H NMR chemical shifts have been computed at the B3LYP/6-31G＊ and B3LYP/6-311G＊＊ levels. Anharmonic corrections to frequencies were obtained by means of second-order perturbation theory （PT2） at the B3LYP/6-31G＊ level. Based on potential energy distribution （PED）, the vibrational assignments have also been performed. The theoretical calculation values were compared with the experimental observations and the results indicate they are in excellent agreement.
文摘The study on ^(13)C-NMR spectra of aliphatic carbon region of emuision-processed and solution-processed (by lithium catalyst) SBR was carried out. The assignments for more than thirty odd peaks observed experimentally were made by using 'corresponding analysis' method, combined with the empirical parameters reported in literature. The peak intensifies were calculated based on BemouUian statistic assumption.
基金funded by the CAMS Innovation Fund for Medical Sciences(CIFMS,No.2021-I2M-1-028).
文摘An approach for distinguishing two types of positional isomers of dimeric shikonin and its analogs was explored with ^(4)JC,H long-range correlation by prolonging the acquisition time at ^(2,3)JC,H values of 2.0 and 8.0Hz.Furthermore,the ^(1)H(proton)nuclear magnetic resonance(NMR)pattern of phenolic hydroxyl protons was developed as a“diagnosis signal”to ascertain the relative location of each side chain in DMSO-d_(6) at sample concentrations of 0.022-0.034 mol/L.The chemical shift differences of 0.6ppm between OH-5' and OH-1 and between OH-8'and OH-4 are assigned to Type A and Type B,respectively.All reported ambiguous structures were corrected by this pattern.Additionally,the steric structures of isolated compounds were elucidated by quantum chemical calculations of electronic circular dichroism(ECD)spectra.
基金the National Key R&D Program of China(2024YFA1306200)National Natural Science Foundation of China(22377119)+2 种基金Anhui Provincial Natural Science Foundation(2208085MC50)USTC Research Funds of the Double First-Class Initiative(YD9100002028,YD9100002036)Research Funds of Center for Advanced Interdisciplinary Science and Biomedicine of IHM(QYPY20220008)for their financial support.
文摘Nuclear magnetic resonance(NMR)spectroscopy is an indispensable tool to probe weak protein-ligand interactions,which are key to the hit identification and hit-to-lead evolution in fragment-based drug discovery(FBDD).The integration of NMR technology in FBDD has facilitated the development of a diverse array of candidate compounds and FDAapproved drugs.Here,we summarized the rapid advancement and application of NMR techniques in contemporary China,which serves as a catalyst for the ongoing prosperousness of fragment-derived inhibitors against various targets.
文摘WITHDRAWAL:Zhang,J.J.,Guo,Y.Q.,Qin,Z.Y.,Wei,C.T.,Hu,Q.H.,Vandeginste,V.,Miao,H.Y.,Yao,P.,and Zhang,P.F.,“Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphological Division and Fractal Models”,Acta Geologica Sinica-English Edition(Accepted Article):https://doi.org/10.1111/1755-6724.15094.
