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2. Application of transcranial Doppler ultrasonography in cardiovascular surgery

Author

ZHOU Ying⁃hua, ZHANG Gui⁃tao, ZHOU Qi⁃lin, MA Ya⁃jun, and LI Shu⁃juan

Subjects
cardiovascular diseases, nervous system diseases, postoperative complications, ultrasonography, doppler, transcranial, review, Neurology. Diseases of the nervous system, RC346-429
Abstract

The neurological complications following cardiovascular surgery can significantly affect the prognosis of patients. As a convenient and non⁃invasive intraoperative neurological monitoring method, transcranial Doppler ultrasonography (TCD) can provide real⁃time assessment of cerebral hemodynamics and microemboli signals, guide the development of neuroprotective strategies, and reduce the brain injury events. This review systematically summarizes the basic methods and technical performance of TCD monitoring, its clinical application in cardiovascular surgery, as well as the main limitations and future trends of this technology, in order to improve perioperative safety.

Published
2024
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4. Enantioselective Diarylcarbene Insertion into Si–H Bonds Induced by Electronic Properties of the Carbenes

Author

Yang, Liang-Liang, Evans, Declan, Xu, Bin, Li, Wen-Tao, Li, Mao-Lin, Zhu, Shou-Fei, Houk, KN, and Zhou, Qi-Lin

Subjects
Electronics, Hydrogen, Methane, Molecular Structure, Silanes, Silicon, Stereoisomerism, Chemical Sciences, General Chemistry
Abstract

Catalytic enantioselection usually depends on differences in steric interactions between prochiral substrates and a chiral catalyst. We have discovered a carbene Si-H insertion in which the enantioselectivity depends primarily on the electronic characteristics of the carbene substrate, and the log(er) values are linearly related to Hammett parameters. A new class of chiral tetraphosphate dirhodium catalysts was developed; it shows excellent activity and enantioselectivity for the insertion of diarylcarbenes into the Si-H bond of silanes. Computational and mechanistic studies show how the electronic differences between the two aryls of the carbene lead to differences in energies of the diastereomeric transition states. This study provides a new strategy for asymmetric catalysis exploiting the electronic properties of the substrates.

Published
2020

7. Rhodium-catalyzed enantioselective C−Ge bond formation by carbene insertion: Efficient access to chiral organogermanes

Author

Han, Ai-Cui, Zhang, Xuan-Ge, Yang, Liangliang, Pan, Jia-Bin, Zou, Hui-Na, Li, Mao-Lin, Xiao, Li-Jun, Zhou, Qi-Lin, Han, Ai-Cui, Zhang, Xuan-Ge, Yang, Liangliang, Pan, Jia-Bin, Zou, Hui-Na, Li, Mao-Lin, Xiao, Li-Jun, and Zhou, Qi-Lin

Abstract

Organogermanium compounds have shown potential as pharmaceuticals and functional materials and have been used as coupling partners in transition metal-catalyzed cross-coupling reactions. Methods for the synthesis of organic germanium compounds, including catalytic C−Ge coupling reactions and hydrogermylations of alkenes or alkynes, have been developed. However, the development of an efficient method for enantioselective C−Ge bond formation and synthesis of chiral organogermanium compounds remains a challenge, impeding the exploration of their functionalities. We herein report a highly enantioselective reaction for the formation of C−Ge bond catalyzed by chiral dirhodium phosphate catalysts, providing an efficient method for the synthesis of chiral organogermanes. The method features a broad substrate scope, good functional group tolerance, and mild reaction conditions. The mechanism of the C−Ge bond formation reaction was studied computationally and experimentally.

Published
2024

11. Multimorbidity of Allergic Conditions in Urban Citizens of Southern China: A Real-World Cross-Sectional Study

Author

Li, Ya-Ting, primary, Hou, Ming-Hui, additional, Lu, Ya-Xin, additional, Chen, Pei-Ran, additional, Dai, Zhen-Yuan, additional, Yang, Li-Fen, additional, Zhang, Ping-Ping, additional, Xiong, Guo-Wei, additional, Liu, Zi-Feng, additional, Zhou, Qi-Lin, additional, Su, Jing, additional, Cheng, Yun, additional, Zhou, Yu-Qi, additional, Tao, Jin, additional, Huang, Xue-Kun, additional, Dai, Min, additional, Zhang, Kun, additional, Zhou, Min, additional, Yang, Qin-Tai, additional, Feng, Pei-Ying, additional, and Chen, Zhuang-Gui, additional

Published
2023
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17. Nickel-Catalyzed Desymmetrizing Cyclization of 1,6-Dienes to Construct Quaternary Stereocenters

Author

Zhao, Tian-Yuan, Li, Ke, Yang, Liangliang, Zhu, Shou-Fei, Zhou, Qi-Lin, Zhao, Tian-Yuan, Li, Ke, Yang, Liangliang, Zhu, Shou-Fei, and Zhou, Qi-Lin

Abstract

A highly enantioselective and diastereoselective nickel-catalyzed desymmetrizing cyclization of 1,6-dienes was developed by using chiral spiro phosphoramidite ligands. The reaction provides a new atom- and step-economical approach to chiral spiro lactones and analogues bearing a quaternary stereocenter. ©

Published
2021

18. Enantioselective Insertion of Alkynyl Carbenes into Si-H Bonds: An Efficient Access to Chiral Propargylsilanes and Allenylsilanes

Author

Yang, Liangliang, Ouyang, Jing, Zou, Hui-Na, Zhu, Shou-Fei, Zhou, Qi-Lin, Yang, Liangliang, Ouyang, Jing, Zou, Hui-Na, Zhu, Shou-Fei, and Zhou, Qi-Lin

Abstract

Chiral propargylsilanes and chiral allenylsilanes have emerged as versatile building blocks for organic synthesis. However, efficient methods for preparing these organosilicon compounds are lacking. We herein report a highly enantioselective method for synthesis of chiral propargylsilanes and chiral allenylsilanes from readily available alkynyl sulfonylhydrazones. Specifically, chiral spiro phosphate dirhodium complexes were used to catalyze asymmetric insertion of alkynyl carbenes into the Si-H bonds of silanes to afford a variety of chiral propargylsilanes with excellent enantioselectivity. Subsequently, a platinum catalyst was used for stereospecific isomerization of the chiral propargylsilanes to the corresponding chiral allenylsilanes. ©

Published
2021

19. Enantioselective Diarylcarbene Insertion into Si-H Bonds Induced by Electronic Properties of the Carbenes

Author

Yang, Liangliang, Evans, Declan, Xu, Bin, Li, Wen-Tao, Li, Mao-Lin, Zhu, Shou-Fei, Houk, K.N., Zhou, Qi-Lin, Yang, Liangliang, Evans, Declan, Xu, Bin, Li, Wen-Tao, Li, Mao-Lin, Zhu, Shou-Fei, Houk, K.N., and Zhou, Qi-Lin

Abstract

Catalytic enantioselection usually depends on differences in steric interactions between prochiral substrates and a chiral catalyst. We have discovered a carbene Si-H insertion in which the enantioselectivity depends primarily on the electronic characteristics of the carbene substrate, and the log(er) values are linearly related to Hammett parameters. A new class of chiral tetraphosphate dirhodium catalysts was developed; it shows excellent activity and enantioselectivity for the insertion of diarylcarbenes into the Si-H bond of silanes. Computational and mechanistic studies show how the electronic differences between the two aryls of the carbene lead to differences in energies of the diastereomeric transition states. This study provides a new strategy for asymmetric catalysis exploiting the electronic properties of the substrates.

Published
2020

23. Enantioselective Nazarov cyclization of indole enones cooperatively catalyzed by Lewis acids and chiral Brønsted acids† †Electronic supplementary information (ESI) available: For CIF data of (R)-3r, experimental procedures, spectral data, and computational study results. CCDC 1539722. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7sc03183a Click here for additional data file. Click here for additional data file. Click here for additional data file

Author

Wang, Guo-Peng, Chen, Meng-Qing, Zhu, Shou-Fei, and Zhou, Qi-Lin

Subjects
Chemistry
Abstract

The first enantioselective Nazarov cyclization of substrates with only one coordinating site and with proton-transfer as an enantioselective-determining step was realized by means of cooperative catalysis with a Lewis acid and a chiral Brønsted acid., Enantioselective control of the chirality of a tertiary α-carbon in the products of a Nazarov cyclization of enones is challenging because the reaction involves an enantioselective proton transfer process. We herein report the use of cooperative catalysis using Lewis acids and chiral Brønsted acids to control the stereochemistry of the tertiary α-carbon in the products of this reaction. Specifically, with ZnCl2 and a chiral spiro phosphoric acid as catalysts, we realized the first enantioselective construction of cyclopenta[b]indoles with chiral tertiary α-carbons via Nazarov cyclization of indole enone substrates with only one coordinating site. Mechanistic studies revealed that the chiral spiro phosphoric acid acts as a multifunctional catalyst: it co-catalyzes the cyclization of the dienone and enantioselectively catalyzes a proton transfer reaction of the enol intermediate. This new strategy of enantioselective control by means of cooperative catalysis may show utility for other challenging asymmetric cyclization reactions.

Published
2017

24. Bioinspired enantioselective synthesis of crinine-type alkaloids via iridium-catalyzed asymmetric hydrogenation of enones† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc02112g Click here for additional data file

Author

Zuo, Xiao-Dong, Guo, Shu-Min, Yang, Rui, Xie, Jian-Hua, and Zhou, Qi-Lin

Subjects
Chemistry
Abstract

A bioinspired enantioselective synthesis of crinine-type alkaloids was developed by iridium-catalyzed asymmetric hydrogenation of enones, providing 24 crinine-type alkaloids and 8 analogues with high yield and high enantioselectivity., A bioinspired enantioselective synthesis of crinine-type alkaloids has been developed by iridium-catalyzed asymmetric hydrogenation of racemic cycloenones. The method features a biomimetic stereodivergent resolution of the substrates bearing a remote arylated quaternary stereocenter. Using this protocol, 24 crinine-type alkaloids and 8 analogues were synthesized in a concise and rapid way with high yield and high enantioselectivity.

Published
2017

25. Intramolecular regioselective insertion into unactivated prochiral carbon-hydrogen bond with diazoacetates of primary alcohols catalyzed by chiral dirhodium(II) carboxamidates: highly enantioselective total synthesis of natural lignan lactones

Author

Bode, Jeffrey W., Doyle, Michael P., Protopopova, Marina N., and Zhou, Qi-Lin

Subjects
Lactones -- Analysis, Macrolide antibiotics -- Analysis, Organic compounds -- Synthesis, Biological sciences, Chemistry
Abstract

A method for the synthesis of natural lignan lactones was developed by utilizing chiral dirhodium(II) carboxamidate catalysts. The synthetic process is characterized by C-H insertion which was initiated by the overlap of the carbon p-orbital and sigma-orbital of the metal carbene and the reacting C-H bond. The formation of beta-substituted-gamma-butyrolactones was initiated by the reaction of chiral Rh2(MPPIM)4 catalysts to fully aliphatic systems.

Published
1997

26. Intramolecular regioselective insertion into unactivated prochiral carbon-hydrogen bond with diazoacetates of primary alcohols catalyzed by chiral dirhodium(II) carboxamidates: highly enantioselective total synthesis of natural lignan lactones

Author

Bode, Jeffrey W., Doyle, Michael P., Protopopova, Marina N., and Zhou, Qi-Lin

Subjects
Lactones -- Analysis, Macrolide antibiotics -- Analysis, Organic compounds -- Synthesis, Biological sciences, Chemistry
Abstract

A method for the synthesis of natural lignan lactones was developed by utilizing chiral dirhodium(II) carboxamidate catalysts. The synthetic process is characterized by C-H insertion which was initiated by the overlap of the carbon p-orbital and sigma-orbital of the metal carbene and the reacting C-H bond. The formation of beta-substituted-gamma-butyrolactones was initiated by the reaction of chiral Rh2(MPPIM)4 catalysts to fully aliphatic systems.

Published
1996

32. Application of Enhanced Recovery After Surgery in Perioperative Period of Tympanoplasty and Mastoidectomy

Author

Tan, Jing-Qian, Chen, Yu-Bin, Wang, Wei-Hao, Zhou, Shao-Li, Zhou, Qi-Lin, and Li, Peng

Abstract

Introduction: Enhanced recovery after surgery (ERAS) protocols are a series of perioperative care to optimize preoperative preparation, prevent postoperative complications, minimize stress, and speedup recovery. Tympanoplasty and mastoidectomy are common surgical procedures for chronic suppurative otitis media.Objective: To compare the efficacy and safety between ERAS and conventional recovery after surgery in the perioperative period of chronic suppurative otitis media.Methods: From April 2018 to February 2019, a total of 84 patients scheduled for tympanoplasty and/or mastoidectomy due to chronic suppurative otitis media were involved and randomly divided into the ERAS group and the control group. The patients’ preoperative anxiety, postoperative pain, and comfort level were determined by comparing the results of Self-Rating Anxiety Scale (SAS), Visual Analog Scale (VAS) and General Comfort Questionnaire (GCQ). The postoperative complications, postoperative hospital stay, and hospitalization cost were calculated.Results: The ERAS group showed a lower SAS score (30 [28-31.5] vs 35 [30-43], P< .05], a higher GCQ score (88 [84-100] vs 83 [78.25-92.25], P< .05), and a lower VAS score (0 [0-0] vs 1 [0-2], P< .05] after surgery. No significant difference (P> .05) was observed between the ERAS group and the control group in postoperative complications, postoperative hospitalization time, and hospitalization cost, respectively.Conclusion: Enhanced recovery after surgery can reduce pain and improve comfort in the perioperative period of chronic suppurative otitis media.

Published
2021
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33. Chiral phosphine-catalyzed tunable cycloaddition reactions of allenoates with benzofuranone-derived olefins for a highly regio-, diastereo- and enantioselective synthesis of spiro-benzofuranones† †Electronic supplementary information (ESI) available: Experimental procedures, characterization data of new compounds. CCDC 961159, 967550 and 1010550. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5sc03135d

Author

Wang, De, Wang, Guo-Peng, Sun, Yao-Liang, Zhu, Shou-Fei, Wei, Yin, Zhou, Qi-Lin, and Shi, Min

Subjects
Chemistry
Abstract

The first regioselective catalytic asymmetric [3 + 2] cycloaddition of benzofuranone-derived olefins with allenoates and substituted allenoates has been developed in the presence of (R)-SITCP., The first regioselective catalytic asymmetric [3 + 2] cycloaddition of benzofuranone-derived olefins with allenoates and substituted allenoates has been developed in the presence of (R)-SITCP, affording different functionalized 3-spirocyclopentene benzofuran-2-ones in good yields with high enantioselectivities under mild conditions. The substrate scope has also been examined. The regioselective outcomes for this phosphine-catalyzed [3 + 2] cycloaddition reaction can be rationalized using DFT calculations.

Published
2015

34. Highly efficient hydrogenation of carbon dioxide to formate catalyzed by iridium(iii) complexes of imine–diphosphine ligands† †Electronic supplementary information (ESI) available: Experimental procedures; spectral data for all new compounds. See DOI: 10.1039/c5sc00248f Click here for additional data file. Click here for additional data file

Author

Liu, Chong, Xie, Jian-Hua, Tian, Gui-Long, Li, Wei, and Zhou, Qi-Lin

Subjects
Chemistry
Abstract

A new iridium catalyst containing an imine–diphosphine ligand was developed for the hydrogenation of CO2 to formate., A new iridium catalyst containing an imine–diphosphine ligand has been developed, which showed high efficiency for the hydrogenation of CO2 to formate (yield up to 99%, TON up to 450 000). A possible catalytic mechanism is proposed, in which the imine group of the catalyst plays a key role in the cleavage of H2 and the activation of CO2.

Published
2015

37. Elevated plasma CXCL12/SDF-1 levels are linked with disease severity of postmenopausal osteoporosis.

Author

Yang, Xian-Wen, Huang, Hong-Xing, Wang, Fei, Zhou, Qi-Lin, Huang, Yan-Qiang, and Qin, Ru-Zi

Subjects
OSTEOPOROSIS in women, DUAL-energy X-ray absorptiometry, FEMUR neck, LUMBAR vertebrae, OSTEOPOROSIS, VERTEBRAE injuries
Abstract

This study was designed to determine whether plasma CXCL12 levels in postmenopausal osteoporosis (PMOP) patients are related to disease severity. A total of 91 PMOP females were recruited, and 88 postmenopausal non-osteoporotic (PMNOP) women and 90 healthy females were incorporated as controls. Dual-energy X-ray absorptiometry was utilised to explore bone-mineral density (BMD). The Genant semi-quantitative grading scale was used for vertebral fractures, and plasma CXCL12/SDF-1 levels were investigated by ELISA. Plasma TNF-α and C-telopeptide cross-linked collagen type 1 (CTX-1) were also tested. The Oswestry Disability Index (ODI) and a visual analogue scale (VAS) were completed in order to assess clinical severity. Plasma CXCL12 levels were considerably elevated in PMOP females compared to PMNOP women and healthy controls. Plasma CXCL12 concentrations were positively correlated with the Genant grading system. We observed significant and negative correlations of plasma CXCL12 levels with lumbar spine, femoral neck and total hip BMD. Moreover, plasma CXCL12 concentrations were positively correlated to VAS and ODI, as well as plasma TNF-α and CTX-1 levels. In conclusion, elevated plasma CXCL12 levels are correlated with disease severity in PMOP females. [ABSTRACT FROM AUTHOR]

Published
2020
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39. Nickel-catalyzed enantioselective hydrovinylation of silyl-protected allylic alcohols: An efficient access to homoallylic alcohols with a chiral quaternary center

Author

Zhu Shou-Fei, Zhou Qi-Lin, Cai Yan, Zhang Qi, and Wang Li-Xin

Subjects
Phosphoramidite, Allylic rearrangement, Silylation, Chemistry, General Chemical Engineering, Enantioselective synthesis, chemistry.chemical_element, General Chemistry, Biochemistry, Catalysis, chemistry.chemical_compound, Nickel, Materials Chemistry, Organic chemistry, Bifunctional, Quaternary carbon
Abstract

An asymmetric hydrovinylation of silyl-protected allylic alcohols catalyzed by nickel complexes of chiral spiro phosphoramidite ligands was developed. A series homoallylic alchols with a chiral quaternary center were produced in high yields (up to 97%) and high enantioselectivities (up to 95% ee). The reaction provided an efficient method for preparing bifunctional compounds with a chiral quaternary carbon center.

Published
2010

46. Magical Chiral Spiro Ligands

Author

Zhou Qi-Lin and Xie Jian-Hua

Subjects
Chemistry, Enantioselective synthesis, General Chemistry, Metal catalyst, Combinatorial chemistry
Published
2014

47. Optimization of enantiocontrol for carbon-hydrogen insertion with chiral dirhodium(II) carboxamidates: synthesis of natural dibenzylbutyrolactone lignans from 3-aryl-1-propyl diazoacetates in high optical purity

Author

Doyle, Michael P., Protopopova, Marina N., Zhou, Qi-Lin, Bode, Jeffrey W., Simonsen, Stanley H., and Lynch, Vincent

Subjects
Rhodium -- Usage, Lactones -- Analysis, Organic compounds -- Synthesis, Biological sciences, Chemistry
Abstract

A new, efficient carbon-hydrogen insertion methodology is used for the highly enantio- and regioselective syntheses of natural dibenzylbutyrolactone lignans from 3-aryl-1-propyl diazoacetates using chiral oxoimidazolidine carboxylate-ligated dirhodium(II) catalysts. The dirhodium catalysts are prepared from m-1-(3-phenylpropanoyl)-2-oxoimidazolidine-4(S)-carboxylate and its 4(R) enantiomer. The openness in the area around the rhodium catalyst, Rh2(4-R-MPPIM)4 allows insertion of the C-H bond.

Published
1995

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