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We report a facile and economical synthesis of α-fluoroacrylic acids via direct electrochemical defluorinative carboxylation of gem-difluoroalkenes with CO2. By using a platinum plate as the working cathode and a cheap nickel plate as the anode in a user-friendly undivided cell under constant current conditions, the reactions proceed smoothly under room temperature, without the use of expensive transition metal catalysts, ligands, external base or reductant, affording the desired adducts in up to 83% yield and 20:1 Z/E ratio, with good functional group tolerance. A cyclic voltammetry study was conducted and suggested a novel ECEC process.

An enantioselective carboxylative cyclization of propargylic alcohols and CO2 was realized under mild conditions, based on a kinetic resolution strategy, which enabled the synthesis of chiral cyclic carbonates and propargylic alcohols with promising yield and enantioselectivity simultaneously.

An unprecedented γ-carboxylation of α-CF3 alkenes with CO2 is reported. This approach constitutes a rare example of using electrochemical methods to achieve regioselectivity complementary to conventional metal catalysis. Accordingly, using platinum plate as both a working cathode and a nonsacrificial anode in a user-friendly undivided cell under constant current conditions, the γ-carboxylation provides efficient access to vinylacetic acids bearing a gem-difluoroalkene moiety from a broad range of substrates. The synthetic utility is further demonstrated by gram-scale synthesis and elaboration to several value-added products. Cyclic voltammetry and density functional theory calculations were performed to provide mechanistic insights into the reaction.

An unprecedented γ-carboxylation of α-CF3 alkenes with CO2 is reported. This approach constitutes a rare example of using electrochemical methods to achieve regioselectivity complementary to conventional metal catalysis. Accordingly, using platinum plate as both a working cathode and a nonsacrificial anode in a user-friendly undivided cell under constant current conditions, the γ-carboxylation provides efficient access to vinylacetic acids bearing a gem-difluoroalkene moiety from a broad range of substrates. The synthetic utility is further demonstrated by gram-scale synthesis and elaboration to several value-added products. Cyclic voltammetry and density functional theory calculations were performed to provide mechanistic insights into the reaction., A γ-carboxylation of α-CF3 alkenes with CO2 using platinum plate as both working cathode and nonsacrificial anode has been developed.

We report a facile and economical synthesis of α-fluoroacrylic acids via direct electrochemical defluorinative carboxylation of

Herein, we report that 1,3-diphenylguanidine (DPG) could be utilized for the carboxylative cyclization of homopropargyl amines with CO2 under ambient temperature and pressure, in combination with AgSbF6, which enabled the synthesis of both chiral and achiral 2-oxazinones efficiently. A mechanistic study revealed that the multi-functionality of DPG is critical to the success of the reaction.

We report the copper-catalyzed defluorinative carboxylation of gem-difluoroalkenes with CO2. Using cheap and easily available CuI as the catalyst and bis(pinacolatodiboron) as the stoichiometric reductant, the reaction efficiently converts the alkenyl C–F bond to a carboxyl group with complete retention of stereochemistry, thus providing fluoroalkenyl carboxylic acids in good to excellent yields.

We report a general and highly efficient Mukaiyama-aldol reaction of ketones and difluoroenoxysilanes. While the reaction of aryl ketones worked efficiently in the presence of Bi(OTf) 3 , that of aliphatic ketones required the use of Sc(OTf) 3 . In addition, Sc(OTf) 3 was capable of achieving excellent 1,2-selectivity in the corresponding reaction of α,β-unsaturated ketones. This method provides a facile access to differently substituted β-hydroxy α,α-difluoro ketones, versatile synthons for difluomethylated tertiary alcohols.

Herein, we report that 1,3-diphenylguanidine (DPG) could be utilized for the carboxylative cyclization of homopropargyl amines with CO2 under ambient temperature and pressure, in combination with AgSbF6, which enabled the synthesis of both chiral and achiral 2-oxazinones efficiently. A mechanistic study revealed that the multi-functionality of DPG is critical to the success of the reaction.

We report the activation of (salen)CoI complex 3g by a phosphorane to form a bifunctional catalyst for the reaction of carbon dioxide with terminal epoxides or aziridines at ambient temperature and 1 bar carbon dioxide pressure. Only 1.0 mol% of both (salen)CoI 3g and phosphorane 4d are required for cyclic carbonate synthesis, and the catalyst loading could even be lowered down to 0.1 mol%. Under these conditions, no polycarbonate formation is detected by NMR analysis. It is proposed that the high efficiency originates from the activation of (salen)CoI by a phosphorane to form a phosphorane–salen Co(III) complex with enhanced Lewis acidity for the electrophilic activation while generating an iodide anion as a Lewis base co-catalyst to facilitate the ring-opening of epoxides. Further investigation revealed that the phosphorane–(salen)CoI complex could also successfully catalyze the coupling of CO2 with aziridines under ambient conditions at a catalyst loading of 2.5 mol%.

To improve the diagnosis and treatment of non-ductal pancreatic adenocarcinoma-occupying lesions.A retrospective analysis was made for 114 cases of pancreatic non-ductal adenocarcinoma-occupying pathologically confirmed lesions.(1) There were 36 males (31.6%) and 78 females (68.42%); (2) presenting symptoms and signs were abdominal pain (n = 56, 49.1%), back pain (n = 24, 21.1%), weight loss (n = 18, 15.8%) and obstructive jaundice (n = 8, 0.07%); (3) the positive rates of CA19-9, CA242 and CEA were 21.1%, 19.7% and 5.6% respectively; (4) pancreaticoduodenectomy was performed in 26 patients, distal pancreatectomy in 53, tumor enucleation in 15, segmental pancreatectomy in 9, partial resection in 3, duodenum-preserving pancreatic head resection in 1 and palliative surgery (either cholecystojejunostomy anastomosis or gastrojejunostomy) in 7; (5) pathologic analysis revealed 35 solid pseudopapillary neoplasm of pancreas, 28 pancreatic endocrine tumors, 18 focal chronic pancreatitis, 11 serous cystic neoplasms, 9 mucinous cystic neoplasms, 4 pancreatic cysts, 3 acinar cell carcinomas, 2 pancreatic cavernous hemangiomas, 1 sarcoma of pancreas, 1 sarcomatoid carcinoma of pancreas, 1 pancreatic schwannoma and 1 pancreatic neuroblastoma.The non-ductal pancreatic adenocarcinoma-occupying lesions have no specific clinical presentation or serum tumor marker. An understanding of the natural history of these lesions is important for optimal management.

To evaluate the effect of atorvastatin on postoperative atrial fibrillation (AF) in patients undergoing coronary artery bypass grafting (CABG).A cohort of 140 consecutive patients without a history of documented AF or previous statin use, who were scheduled to undergo selective CABG, were enrolled. Included patients were randomly assigned to atorvastatin group (n = 71) who were administered atorvastatin 20 mg/d or to control group (n = 69). After CABG, subjects were monitored continuously by electrocardiographic monitors at least 7 days. During the initial postoperative 7 d, the incidence and duration of AF were recorded. And the levels of high-sensitivity C-reactive protein (hs-CRP) were measured before and 24 hours, 72 hours, 7 days after operation, respectively. The statistical software package SPSS (version 13.0) were used to analyze the data. The differences between groups were evaluated by chi(2)-test for discrete variables and student t-test for continuous variables. Multivariate logistic regression analysis was performed to determine the independent predictors of early postoperative AF.During initial postoperative 7 d, AF occurred at least once in 10 cases in atorvastatin group, with a prevalence of roughly 14%, and in 23 cases in control group, with a prevalence of approximately 34% (P = 0.009). The mean duration of single AF was 3.6 +/- 0.4 hours in atorvastatin group and 5.7 +/- 0.5 hours in control group (P0.01), respectively. The multivariate logistic analysis showed that perioperative atorvastatin administration was an independently risk factor for early postoperative AF (OR = 0.219, 0.076-0.633, P = 0.005). There was also statistical difference in hs-CRP after CABG between the two groups.Perioperative atorvastatin administration may inhibit inflammatory reaction, reduce the incidence and duration of postoperative AF, hence may prevent and treat postoperative AF.

To evaluate the effect and timing of continuous blood purification (CBP) in treatment of acute renal failure (ARF) following cardiac-vascular surgery.Twenty-five patients with ARF following cardiac-vascular surgery were divided into systematic inflammatory response syndrome (SIRS) Group (n = 13) and multiple organ dysfunction syndrome (MODS) Group (n = 12) according to the illness state prior to CBP and were divided into Group A (n = 5, with the APACHEIII score prior to CBPor= 60), Group B (n = 9, with the APACHEIII score 61 - 90), and Group C (n = 11, with the APACHEIII score90). All of the 25 patients underwent continuous veno-venous hemofiltration (CVVH). Before and 24h after the CVVH APACHEIII score was calculated and [peripheral; blood samples were collected to detect the levels of blood urea nitrogen (BUN) and serum creatinine (Scr) and the plasma levels of interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-alpha (TNF-alpha).The APACHEIII score, BUN, Scr, IL6, IL8, and TNFalpha 24 h after the CBP of the 25 patients were 61 +/- 15 mmol/L, (19 +/- 5) mmol/L, (312 +/- 87) micromol/L, (544 +/- 154) ng/L, (18 +/- 7) ng/L, and (43 +/- 15) ng/L respectively, all significantly lower than those before CBP (81 +/- 20, 26 +/- 5 mmol/L, 458 +/- 107 micromol/L, (842 +/- 132) ng/L, (25 +/- 8) ng/L, and (59 +/- 17) ng/L respectively, all P = 0.000). The survival rate of SIRS Group was 84.62%, significantly higher than that of MODS Group (41.67%, P0.05). The APACHEIII score, and the levels of BUN, Scr, IL6, IL8, and TNF-alpha of Group MODS were significantly higher than those of Group SIRS. The higher the level of Scr, IL6, IL8, and TNF-alpha and the APACHEIII score the lower the survival rate.CBP has a positive effect on ARF following cardiac-vascular surgery. The APACHEIII score 60 to 90 reflects an opportunity to treat the ARF following cardiac-vascular surgery using CBP.

To assess the long- term efficacy of surgical treatment of hepatic metastases from gastric adenocarcinoma.Clinical data of 938 cases with primary gastric cancer from January 1993 to October 2001 were analyzed retrospectively. Thirty- two cases received resection of hepatic metastases from gastric adenocarcinoma.Metachronous hepatic metastasis occurred in 24 cases(2.6% ),and 14 cases(58.3% ) underwent resection of hepatic metastases, while synchronous hepatic metastasis occurred in 90 cases(9.6% ) and 18 cases(20% ) underwent resection of hepatic metastases. The 1- 3- 5- year survival rates of hepatic resection for metachronous hepatic metastases were 73% 37% 25% respectively; while for synchronous hepatic metastases 68% 24% and 17% respectively. There were no significant differences between the two groups (P0.05).Synchronous and metachronous hepatic metastases from gastric cancer should be treated by surgical resection to confirm a better prognosis.

To discuss the long-term effect of united liver and spleen resection on treatment of hepatocellular carcinoma (HCC) complicated with cirrhosis and hypersplenism.The clinical data of 102 patients of HCC complicated with cirrhosis and hypersplenism, 57 receiving united hepatectomy and splenectomy (group A), and 45 receiving hepatectomy only (group B), were retrospectively examined.The volume of operative blood loss of group A was 765 ml (100 - 2,400 ml), not significantly different from that of group B (720 ml, 200 - 2,000 ml). The operative morbidity was 1.7% (1/57) of group A, significantly higher lower than that of group B (4.4%, 2/45). After the operation, the platelet count increased to 275.8 x 10(9)/L in group A, significantly higher than that in group B (83 x 10(9)/L, P0.05); and the white blood cell count of group A increased to 10.4 x 10(9)/L, significantly higher than that of group B (4.19 x 10(9)/L, P0.05). Post-operative gamma glutamyl transferase, a prognostic factor for liver cirrhosis, of group A was 68 U/L, significantly lower than that of group B (132 U/L, P0.05). The incidence of complication was 29.8% (17/57) in group A, not significantly different from that of group B (33.3%, 15/45). The 1, 3, and 5-year recurrence rates were 27.1%, 48.6%, and 69.3% in group A, versus 41.2%, 50.0%, and 77.9% in group B, whereas the 1, 3, and 5-year survival rates were 92.6%, 59.1%, and 41.8% in group A, versus 80.3%, 43.9%, and 29.1% in the group B. The longest survival time in group A was 12.9 months, significantly longer than that in group B (6.3 months, P0.01).United liver and spleen resection is a safe and effective modality for the treatment of HCC complicated with cirrhosis and hypersplenism.