A facile Tf OH-catalyzed oxidative cyclization of allyl compounds and isocyanide has been developed with the assistance of DDQ, where isocyanide is used as the crucial "N" and "CN" sources. Highly ...A facile Tf OH-catalyzed oxidative cyclization of allyl compounds and isocyanide has been developed with the assistance of DDQ, where isocyanide is used as the crucial "N" and "CN" sources. Highly functionalized 2-cyanopyrroles are constructed efficiently through a new formal [3 + 2] mode, demonstrating diverse reactivity and synthetic utility in organic chemistry. 2-Cyanopyrrole is converted into a nucleobase analogue of Remdesivir and 5H-pyrrolo[2,1-a]isoindole through a three-step or a two-step sequence, respectively. This protocol features broad substrate scope, operational simplicity and good functional group tolerance.展开更多
In the presence of BiCl3/Al or BiCl3/Fe, in THF-H2O, allylic (benzylic) bromides or α-bromoketones react with diorganyl diselenides to give allylic (benzylic) selenides orα-organylselenocarbonyl compounds respective...In the presence of BiCl3/Al or BiCl3/Fe, in THF-H2O, allylic (benzylic) bromides or α-bromoketones react with diorganyl diselenides to give allylic (benzylic) selenides orα-organylselenocarbonyl compounds respectively in moderate to good yields.展开更多
以双马来酰亚胺(MBMI)为基体,3,3′-二烯丙基双酚A(BBA)和双酚A双烯丙基醚(BBE)为活性稀释剂,环氧树脂(EP)为增韧剂,4,4′-二氨基二苯甲烷(DDM)为固化剂,制备了改性双马来酰亚胺树脂(EP-MBMI),并对其性能进行研究。结果表明:随着EP含量...以双马来酰亚胺(MBMI)为基体,3,3′-二烯丙基双酚A(BBA)和双酚A双烯丙基醚(BBE)为活性稀释剂,环氧树脂(EP)为增韧剂,4,4′-二氨基二苯甲烷(DDM)为固化剂,制备了改性双马来酰亚胺树脂(EP-MBMI),并对其性能进行研究。结果表明:随着EP含量的增加,材料的弯曲强度呈先上升后下降的趋势,当EP含量为20%时,EP-MBMI体系的弯曲强度最大,为134.5 MPa,比MBMI的弯曲强度提高了22.8%。另外,EP-MBMI体系的介电常数随EP含量的增加呈下降的趋势,且在环氧树脂含量在20%时介电常数达到最小值;介质损耗随EP含量的增加有所增加,但数量级均为10-3;EP-MBMI体系的体积电阻率及电气强度随EP含量的增加呈先增大后减小的趋势,并分别在EP含量为15%及20%时取得最大值,分别为4.87×1015Ω·m和15.66 k V/mm。展开更多
AIM: To develop and optimize cDNA representational difference analysis (cDNA RDA) method and to identify and clone garlic up-regulated genes in human gastric cancer (HGC) cells. METHODS: We performed cDNA RDA method b...AIM: To develop and optimize cDNA representational difference analysis (cDNA RDA) method and to identify and clone garlic up-regulated genes in human gastric cancer (HGC) cells. METHODS: We performed cDNA RDA method by using abundant double-stranded cDNA messages provided by two self-constructed cDNA libraries (Allitridi-treated and paternal HGC cell line BGC823 cells cDNA libraries respectively). Bam H I and Xho I restriction sites harbored in the library vector were used to select representations. Northern and Slot blots analyses were employed to identify the obtained difference products. RESULTS: Fragments released from the cDNA library vector after restriction endonuclease digestion acted as good marker indicating the appropriate digestion degree for library DNA. Two novel expressed sequence tags (ESTs) and a recombinant gene were obtained. Slot blots result showed a 8-fold increase of glia-derived nexin/protease nexin 1 (GDN/PN1) gene expression level and 4-fold increase of hepatitis B virus x-interacting protein (XIP) mRNA level in BGC823 cells after Allitridi treatment for 72h. CONCLUSION: Elevated levels of GDN/PN1 and XIP mRNAs induced by Allitridi provide valuable molecular evidence for elucidating the garlic's efficacies against neurodegenerative and inflammatory diseases. Isolation of a recombinant gene and two novel ESTs further show cDNA RDA based on cDNA libraries to be a powerful method with high specificity and reproducibility in cloning differentially expressed genes.展开更多
基金the National Natural Science Foundation of China(Nos.22171178, 21871174, 22071143)Innovation Program of Shanghai Municipal Education Commission (No.2019–01–07–00–09-E00008) for financial support。
文摘A facile Tf OH-catalyzed oxidative cyclization of allyl compounds and isocyanide has been developed with the assistance of DDQ, where isocyanide is used as the crucial "N" and "CN" sources. Highly functionalized 2-cyanopyrroles are constructed efficiently through a new formal [3 + 2] mode, demonstrating diverse reactivity and synthetic utility in organic chemistry. 2-Cyanopyrrole is converted into a nucleobase analogue of Remdesivir and 5H-pyrrolo[2,1-a]isoindole through a three-step or a two-step sequence, respectively. This protocol features broad substrate scope, operational simplicity and good functional group tolerance.
基金the Natural Science Foundation of the Education Commission of Jiangsu Province
文摘In the presence of BiCl3/Al or BiCl3/Fe, in THF-H2O, allylic (benzylic) bromides or α-bromoketones react with diorganyl diselenides to give allylic (benzylic) selenides orα-organylselenocarbonyl compounds respectively in moderate to good yields.
文摘以双马来酰亚胺(MBMI)为基体,3,3′-二烯丙基双酚A(BBA)和双酚A双烯丙基醚(BBE)为活性稀释剂,环氧树脂(EP)为增韧剂,4,4′-二氨基二苯甲烷(DDM)为固化剂,制备了改性双马来酰亚胺树脂(EP-MBMI),并对其性能进行研究。结果表明:随着EP含量的增加,材料的弯曲强度呈先上升后下降的趋势,当EP含量为20%时,EP-MBMI体系的弯曲强度最大,为134.5 MPa,比MBMI的弯曲强度提高了22.8%。另外,EP-MBMI体系的介电常数随EP含量的增加呈下降的趋势,且在环氧树脂含量在20%时介电常数达到最小值;介质损耗随EP含量的增加有所增加,但数量级均为10-3;EP-MBMI体系的体积电阻率及电气强度随EP含量的增加呈先增大后减小的趋势,并分别在EP含量为15%及20%时取得最大值,分别为4.87×1015Ω·m和15.66 k V/mm。
基金the Natural Scientific Foundation of China (NSFC3962526)National High-Technology Project-863 (102-10-01-04)
文摘AIM: To develop and optimize cDNA representational difference analysis (cDNA RDA) method and to identify and clone garlic up-regulated genes in human gastric cancer (HGC) cells. METHODS: We performed cDNA RDA method by using abundant double-stranded cDNA messages provided by two self-constructed cDNA libraries (Allitridi-treated and paternal HGC cell line BGC823 cells cDNA libraries respectively). Bam H I and Xho I restriction sites harbored in the library vector were used to select representations. Northern and Slot blots analyses were employed to identify the obtained difference products. RESULTS: Fragments released from the cDNA library vector after restriction endonuclease digestion acted as good marker indicating the appropriate digestion degree for library DNA. Two novel expressed sequence tags (ESTs) and a recombinant gene were obtained. Slot blots result showed a 8-fold increase of glia-derived nexin/protease nexin 1 (GDN/PN1) gene expression level and 4-fold increase of hepatitis B virus x-interacting protein (XIP) mRNA level in BGC823 cells after Allitridi treatment for 72h. CONCLUSION: Elevated levels of GDN/PN1 and XIP mRNAs induced by Allitridi provide valuable molecular evidence for elucidating the garlic's efficacies against neurodegenerative and inflammatory diseases. Isolation of a recombinant gene and two novel ESTs further show cDNA RDA based on cDNA libraries to be a powerful method with high specificity and reproducibility in cloning differentially expressed genes.
