Renewable resources based polymers provides a sustainable alternative to petroleum derived polymeric materials.As a part of our series on synthesis of vanillin based renewable polymers,we report the synthesis of poly(...Renewable resources based polymers provides a sustainable alternative to petroleum derived polymeric materials.As a part of our series on synthesis of vanillin based renewable polymers,we report the synthesis of poly(hydrovanilloin-furfural)[poly(HVL-Fur)]and poly(hydrovanilloin–5-hydromethylfurfural)[poly(HVL-5-HMF)].Vanillin was dimerized to a mixtures of meso/DL-hydrovanilloins with 94%meso product by electrochemical reductive coupling in aqueous sodium hydroxide using lead electrodes in quantitative yield.Then sodium hydroxide catalyzed condensation of hydrovanilloin with furfural in water at 80℃for 72 h was used to synthesize poly(HVL-Fur)with Mw=8600 g mol^(−1),PDI=1.28 in 78%yield.Similarly,condensation of hydrovanilloin with 5-hydroxymethylfurfural at 80℃for 48 h produced poly(HVL-5-HMF)with Mw=12,100 g mol−1,PDI=1.27 in 68%yield.poly(HVL-Fur)and poly(HVL-5-HMF)showed similar Tg values of 59℃and 60℃,respectively;whereas melting behaviors are dissimilar with Tm 171℃–173℃and 148℃–182℃,respectively.展开更多
Hydrogenative rearrangement of biomas s-derived furfurals(furfural and 5-hydroxymethyl furfural) to C_(5) cyclic compounds(such as cyclopentanones and cyclopentanols) offers an expedient reaction route for acquiring O...Hydrogenative rearrangement of biomas s-derived furfurals(furfural and 5-hydroxymethyl furfural) to C_(5) cyclic compounds(such as cyclopentanones and cyclopentanols) offers an expedient reaction route for acquiring O-containing value-added chemicals thereby replacing the traditional petroleum-based approaches.The scope for developing efficient bifunctional catalysts and establishing mild reaction conditions for upgrading furfurals to cyclic compounds has stimulated immense deliberation in recent years.Extensive efforts have been made toward developing catalysts for multiple tandem conversions,including those with various metals and supports.In this scientific review,we aim to summarize the research progress on the synergistic effect of the metal-acid sites,including simple metal-supported acidic supports,adjacent metal acid sites-supported catalysts,and in situ H_(2)-modified bifunctional catalysts.Distinctively,the catalytic performance,catalytic mechanism,and future challenges for the hydrogenative rearrangement are elaborated in detail.The methods highlighted in this review promote the development of C_(5) cyclic compound synthesis and provide insights to regulate bifunctional catalysis for other applications.展开更多
In the present study, we hypothesized that 5-hydroxymethyl-2-furfural could attenuate ischemic brain damage by reducing oxidative injury. Thus, mice were subjected to bilateral common carotid artery occlusion to estab...In the present study, we hypothesized that 5-hydroxymethyl-2-furfural could attenuate ischemic brain damage by reducing oxidative injury. Thus, mice were subjected to bilateral common carotid artery occlusion to establish a model of permanent forebrain ischemia. The mice were intraperitoneally injected with 5-hydroxymethyl-2-furfura130 minutes before ischemia or 5 minutes after ischemia. The survival time of mice injected with 5-hydroxymethyl-2-furfural was longer compared with untreated mice. The mice subjected to ischemia for 30 minutes and reperfusion for 5 minutes were intraperitoneally injected with 5-hydroxymethyl-2-furfural 5 minutes prior to reperfusion, which increased superoxide dismutase content and reduced malondialdehyde content, similar to the effects of Edaravone, a hydroxyl radical scavenger used for the treatment of stroke. These findings indicate that intraperitoneal injection of 5-hydroxymethyl-2-furfural can prolong the survival of mice with permanent forebrain ischemia. This outcome may be mediated by its antioxidative effects.展开更多
Previous studies have shown that 5-hydroxymethylfurfural, a compound extracted from wine- processed Fructus corni, has a protective effect on hippocampal neurons. The present study was designed to explore the related ...Previous studies have shown that 5-hydroxymethylfurfural, a compound extracted from wine- processed Fructus corni, has a protective effect on hippocampal neurons. The present study was designed to explore the related mechanisms. Our study revealed that high and medium doses (10, 1 μmol/L) of 5-hydroxymethylfurfural could improve the morphology of H2O2-treated rat hippocampal neurons as revealed by inverted phase-contrast microscopy and transmission electron microscopy. MTT results showed that incubation with high and medium doses of 5-hydroxymethylfurfural caused a significant increase in the viability of neuronal cells injured by H2O2. Flow cytometry assays con- firmed that H2O2 could induce cell apoptosis, while high and medium doses of 5-hydroxymethylfurfural had a visible protective effect on apoptotic rat hippocampal neurons. Real-time PCR and western blot analysis showed that high and medium doses of 5-hydroxymethylfurfural prevented H2O2-induced up-regulation of p53, Bax and caspase-3 and an- tagonized the down-regulation of Bcl-2 induced by H2O2 treatment. These results suggested that 5-hydroxymethylfurfural could inhibit apoptosis of cultured rat hippocampal neurons injured by H2O2 via increase in Bcl-2 levels and decrease in p53, Bax and caspase-3 protein expression levels.展开更多
利用碱处理结合柠檬酸处理技术对商业微孔ZSM-5分子筛改性,制备了多级孔ZSM-5分子筛催化剂(ZSM-5-AT-CA)。利用XRD、N_(2)吸脱附、NH_(3)-TPD、Py-IR、^(27)Al MAS NMR等表征技术研究了ZSM-5-AT-CA催化剂的形貌结构和物理化学性质,以5-...利用碱处理结合柠檬酸处理技术对商业微孔ZSM-5分子筛改性,制备了多级孔ZSM-5分子筛催化剂(ZSM-5-AT-CA)。利用XRD、N_(2)吸脱附、NH_(3)-TPD、Py-IR、^(27)Al MAS NMR等表征技术研究了ZSM-5-AT-CA催化剂的形貌结构和物理化学性质,以5-羟甲基糠醛(HMF)自醚化制双-(5-甲酰基糠基)醚(OBMF)为模型反应进一步考察其催化性能。结果表明,ZSM-5-AT-CA催化剂具有多级孔结构(微孔、介孔)、适宜酸位点浓度和强度,有利于HMF自醚化反应。多级孔ZSM-5-AT-CA催化剂在反应温度90℃时HMF转化率达到91.2%,OBMF产率为73.6%。催化剂具有良好的循环稳定性。展开更多
Six hydrophobic peptidyl and four amino acid (L-Val, L-Leu, L-Phe, L-Gly) derivatives of 5-fluorouracil(5-FU) were synthesized. The structure of these compounds were characterized by ~1H-NMR, IR, UV spectra and elemen...Six hydrophobic peptidyl and four amino acid (L-Val, L-Leu, L-Phe, L-Gly) derivatives of 5-fluorouracil(5-FU) were synthesized. The structure of these compounds were characterized by ~1H-NMR, IR, UV spectra and elemental analysis. The antitumor activity was test- ed against EAC cells in vitro.展开更多
基金funded by United States National Science Foundation(NSF)Grant HRD-1036593USDA-NIFA Grant 12684238:Award No.2020-65209-31474United States Department of Energy Grant DE-SC0023345.
文摘Renewable resources based polymers provides a sustainable alternative to petroleum derived polymeric materials.As a part of our series on synthesis of vanillin based renewable polymers,we report the synthesis of poly(hydrovanilloin-furfural)[poly(HVL-Fur)]and poly(hydrovanilloin–5-hydromethylfurfural)[poly(HVL-5-HMF)].Vanillin was dimerized to a mixtures of meso/DL-hydrovanilloins with 94%meso product by electrochemical reductive coupling in aqueous sodium hydroxide using lead electrodes in quantitative yield.Then sodium hydroxide catalyzed condensation of hydrovanilloin with furfural in water at 80℃for 72 h was used to synthesize poly(HVL-Fur)with Mw=8600 g mol^(−1),PDI=1.28 in 78%yield.Similarly,condensation of hydrovanilloin with 5-hydroxymethylfurfural at 80℃for 48 h produced poly(HVL-5-HMF)with Mw=12,100 g mol−1,PDI=1.27 in 68%yield.poly(HVL-Fur)and poly(HVL-5-HMF)showed similar Tg values of 59℃and 60℃,respectively;whereas melting behaviors are dissimilar with Tm 171℃–173℃and 148℃–182℃,respectively.
基金support from the National Natural Science Foundation of China (Nos. 22178158, 52162014 and 22065024)Science and Technology Project of Education Department of Jiangxi Province (No. GJJ2200402)+3 种基金Jiangxi Provincial Natural Science Foundation (No. 20224BAB213023)the Outstanding Youth Science Fund Project of Jiangxi Province (No. 20224ACB213008)the Jiangxi Provincial Double Thousand Talents Plan-Youth Program (No. S2021GDQN0947)Natural Science Foundation of Chongqing (No. 2023NSCQ-MSX0052)
文摘Hydrogenative rearrangement of biomas s-derived furfurals(furfural and 5-hydroxymethyl furfural) to C_(5) cyclic compounds(such as cyclopentanones and cyclopentanols) offers an expedient reaction route for acquiring O-containing value-added chemicals thereby replacing the traditional petroleum-based approaches.The scope for developing efficient bifunctional catalysts and establishing mild reaction conditions for upgrading furfurals to cyclic compounds has stimulated immense deliberation in recent years.Extensive efforts have been made toward developing catalysts for multiple tandem conversions,including those with various metals and supports.In this scientific review,we aim to summarize the research progress on the synergistic effect of the metal-acid sites,including simple metal-supported acidic supports,adjacent metal acid sites-supported catalysts,and in situ H_(2)-modified bifunctional catalysts.Distinctively,the catalytic performance,catalytic mechanism,and future challenges for the hydrogenative rearrangement are elaborated in detail.The methods highlighted in this review promote the development of C_(5) cyclic compound synthesis and provide insights to regulate bifunctional catalysis for other applications.
基金supported by the National Basic Research Program of China (973 Program),No.2003CB517104the National Natural Science Foundation of China,No.30973513+3 种基金Beijing Municipal Science and Technology Program,No.D0206001043191the Natural Science Foundation of Beijing,No.7112061Beijing Key Foundation of Traditional Chinese Medicine,No.KJTS2011-04Beijing Health and Technical Personal of High-Level Plan,No.2009-3-66
文摘In the present study, we hypothesized that 5-hydroxymethyl-2-furfural could attenuate ischemic brain damage by reducing oxidative injury. Thus, mice were subjected to bilateral common carotid artery occlusion to establish a model of permanent forebrain ischemia. The mice were intraperitoneally injected with 5-hydroxymethyl-2-furfura130 minutes before ischemia or 5 minutes after ischemia. The survival time of mice injected with 5-hydroxymethyl-2-furfural was longer compared with untreated mice. The mice subjected to ischemia for 30 minutes and reperfusion for 5 minutes were intraperitoneally injected with 5-hydroxymethyl-2-furfural 5 minutes prior to reperfusion, which increased superoxide dismutase content and reduced malondialdehyde content, similar to the effects of Edaravone, a hydroxyl radical scavenger used for the treatment of stroke. These findings indicate that intraperitoneal injection of 5-hydroxymethyl-2-furfural can prolong the survival of mice with permanent forebrain ischemia. This outcome may be mediated by its antioxidative effects.
基金the National Basic Research Program of China,the National Natural Science Foundation of China,the Key Research Program of the Chinese Academy of Sciences,the Creative Foundation of President of Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences
基金financially supported by the National Natural Science Foundation of China,No.30772851a grant from the Six Talents Peaks Program of Jiangsu Province,Chinaa grant from the Priority Academic Program Development of Jiangsu Higher Education Institutions,PAPD(Traditional Chinese medicine combined with Western Medicine
文摘Previous studies have shown that 5-hydroxymethylfurfural, a compound extracted from wine- processed Fructus corni, has a protective effect on hippocampal neurons. The present study was designed to explore the related mechanisms. Our study revealed that high and medium doses (10, 1 μmol/L) of 5-hydroxymethylfurfural could improve the morphology of H2O2-treated rat hippocampal neurons as revealed by inverted phase-contrast microscopy and transmission electron microscopy. MTT results showed that incubation with high and medium doses of 5-hydroxymethylfurfural caused a significant increase in the viability of neuronal cells injured by H2O2. Flow cytometry assays con- firmed that H2O2 could induce cell apoptosis, while high and medium doses of 5-hydroxymethylfurfural had a visible protective effect on apoptotic rat hippocampal neurons. Real-time PCR and western blot analysis showed that high and medium doses of 5-hydroxymethylfurfural prevented H2O2-induced up-regulation of p53, Bax and caspase-3 and an- tagonized the down-regulation of Bcl-2 induced by H2O2 treatment. These results suggested that 5-hydroxymethylfurfural could inhibit apoptosis of cultured rat hippocampal neurons injured by H2O2 via increase in Bcl-2 levels and decrease in p53, Bax and caspase-3 protein expression levels.
文摘利用碱处理结合柠檬酸处理技术对商业微孔ZSM-5分子筛改性,制备了多级孔ZSM-5分子筛催化剂(ZSM-5-AT-CA)。利用XRD、N_(2)吸脱附、NH_(3)-TPD、Py-IR、^(27)Al MAS NMR等表征技术研究了ZSM-5-AT-CA催化剂的形貌结构和物理化学性质,以5-羟甲基糠醛(HMF)自醚化制双-(5-甲酰基糠基)醚(OBMF)为模型反应进一步考察其催化性能。结果表明,ZSM-5-AT-CA催化剂具有多级孔结构(微孔、介孔)、适宜酸位点浓度和强度,有利于HMF自醚化反应。多级孔ZSM-5-AT-CA催化剂在反应温度90℃时HMF转化率达到91.2%,OBMF产率为73.6%。催化剂具有良好的循环稳定性。
文摘Six hydrophobic peptidyl and four amino acid (L-Val, L-Leu, L-Phe, L-Gly) derivatives of 5-fluorouracil(5-FU) were synthesized. The structure of these compounds were characterized by ~1H-NMR, IR, UV spectra and elemental analysis. The antitumor activity was test- ed against EAC cells in vitro.