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Photocycloaddition of (4-methyl-7-coumarinyl) Oxyacetic Acid Propanediol Diester and X-ray Crystal Structure of Product
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作者 杜大明 孟继本 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1995年第4期272-276,共5页
The photocycloaddition of (4-methyl-7-coumarinyl) oxyacetic acid propanediol diester 1 (C_27H_24O_10) in chloroform produced a single product 2 characterized to be syn head-tail. Crystal structure of 2 has been determ... The photocycloaddition of (4-methyl-7-coumarinyl) oxyacetic acid propanediol diester 1 (C_27H_24O_10) in chloroform produced a single product 2 characterized to be syn head-tail. Crystal structure of 2 has been determined by X-ray diffraction analysis. The crystal belongs to orthorhombic system, space group Pbca, with cell parameters a=10. 745(5), b= 13. 443(4), c=33. 358(9) A, V=4791 (5) A ̄3, M_r=508. 49,Z= 8, D_c=1. 41 g/cm ̄3, μ= 1. 015 cm ̄-1, F(000)=1064. The final R=0. 065 for 1587 observed reflections. Compound 2 has a large ring resulted from [2+2] photocycloaddition. The four-member ring of 2 has poor coplanarity, the two diagonal atoms of four-member ring are above the least-squares plane, and another diagonal atom couple is below the least-squares plane, the deviations of two couples are approximately equal. 展开更多
关键词 PHOTOCYCLOADDITION coumarin derivative crystal structure
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Organocatalyzed Highly Efficient Michael Addition of Malonate Derivatives to α,β-Unsaturated Ketones Using Chiral Schiff Bases
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作者 Yonghai Hui Jianzhong Zhang +1 位作者 Wanfu Sun Zhengfeng Xie 《Journal of Chemistry and Chemical Engineering》 2011年第9期847-853,共7页
An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temp... An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temperature. 展开更多
关键词 α β-unsaturated ketones cyanoacetate MALONATE Michael addition Schiffbase.
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溶剂结晶法直接制备HMX粒度分级产品 被引量:13
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作者 曹端林 徐春彦 +2 位作者 郑志花 轩春雷 陈树森 《火炸药学报》 CAS CSCD 2002年第4期19-22,共4页
在丙酮 -乙酸乙酯溶剂中 ,加入醋酐法生产的粗品α- HMX,根据结晶、转晶原理 ,通过控制适当的工艺条件和恰当的操作方式 ,使α- HMX全部转化为β- HMX,同时直接制备出 A、C、D、F四个不同粒度级别的产品。
关键词 溶剂结晶法 制备 α-HMX 粒度分级产品 丙酮-乙酸酯
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Delayed ethyl pyruvate therapy attenuates experimental severe acute pancreatitis via reduced serum high mobility group box 1 levels in rats 被引量:23
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作者 Zhi-Yong Yang Yan Ling Tao Yin Jing Tao Jiong-Xin Xiong He-Shui Wu Chun-You Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第28期4546-4550,共5页
AIM: To investigate the effect of delayed ethyl pyruvate (EP) delivery on distant organ injury, survival time and serum high mobility group box 1 (HMGB1) levels in rats with experimental severe acute pancreatitis... AIM: To investigate the effect of delayed ethyl pyruvate (EP) delivery on distant organ injury, survival time and serum high mobility group box 1 (HMGB1) levels in rats with experimental severe acute pancreatitis (SAP). METHODS: A SAP model was induced by retrograde injection of artificial bile into the pancreatic ducts of rats. Animals were divided randomly into three groups (n = 32 in each group): sham group, SAP group and delayed EP treatment group. The rats in the delayed EP treatment group received EP (30 mg/kg) at 12 h, 18 h and 30 h after induction of SAP. Animals were sacrificed, and samples were obtained at 24 h and 48 h after induction of SAP. Serum HMGB1, aspartate arninotransferase (AST), alanine arninotransferase (ALT), blood urea nitrogen (BUN), and creatinine (Cr) levels were measured. Lung wet-to-dry-weight (W/D) ratios and histological scores were calculated to evaluate lung injury. Additional experiments were performed between SAP and delayed EP treatment groups to study the influence of EP on survival times of SAP rats. RESULTS: Delayed EP treatment significantly reduced serum HMGB1 levels, and protected against liver, renal and lung injury with reduced lung W/D ratios (8.22 ±0.42 vs 9.76 ± 0.45, P 〈 0.01), pulmonary histological scores (7.1 ± 0.7 vs 8.4 ± 1.1, P 〈 0.01), serum AST (667 ± 103 vs 1 368 ± 271, P 〈 0.01), ALT (446 ± 91 vs 653 ± 98, P 〈 0.01) and Cr (1.2 ± 0.3 vs 1.8 ± 0.3, P 〈 0.01) levels. SAP rats had a median survival time of 44 h. Delayed EP treatment significantly prolonged median survival time to 72 h (P 〈 0.01). CONCLUSION: Delayed EP therapy protects against distant organ injury and prolongs survival time via reduced serum HMGBllevels in rats with experimental SAP. EP may potentially serve as an effective new therapeutic option against the inflammatory response and multiple organ dysfunction syndrome (MODS) in SAP patients. 展开更多
关键词 Severe acute pancreatitis Ethyl pyruvate High mobility group box 1 multiple organ dysfunction syndrome Survival time
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