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Org Lett ; 23(17): 6750-6755, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34406770


The catalytic diastereo- and enantioselective syntheses of C2-symmetric axially chiral 1,4-dicarbonyl derivatives with 2,3-quaternary stereocenters were achieved by utilizing an organo-/iodine binary catalytic strategy. The reactions proceeded well under mild conditions without metals or strong bases.

Front Oncol ; 10: 1611, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850465


PURPOSE: Gastric sarcomatoid carcinoma (GSC) is a very rare malignant tumor. The purpose of this study is to describe the clinical, computed tomography (CT), and pathologic features of GSC to increase awareness of this entity. METHODS: The CT features and clinical data of five patients with pathologically documented GSC were retrospectively analyzed and compared with the corresponding data of gastric adenocarcinoma and lymphoma. RESULTS: Among the 5 patients, 4 were male, and 1 was female. The median age was 59 years. Of the 5 cases of GSC, 3 were in the gastric fundus and cardia, 1 was in the gastric body, and 1 was in the gastric fundus. The gastric wall had local thickening in 4 cases and mass formation in 1 case, with stenosis and deformation of the adjacent gastric cavity. The long-axis diameter of the lesions ranged from 1.4 to 10.2 cm (mean, 4.97 cm) and was <10 cm in 4 cases and >10 cm in 1 case. The tumor showed predominantly inhomogeneous density, with radiodensity values ranging from 30 to 53 HU. In addition, ulcers with an irregular base and slightly raised borders were observed in 4 of 5 cases. After an injection of contrast material, heterogeneous (n = 4) or homogeneous (n = 1) enhancement was observed. After contrast medium injection, obvious enhancement was seen in 2 cases, and moderate enhancement was seen in 3 cases; the peak tumor signal was observed in the portal phase. Two of the patients demonstrated evidence of lymph node involvement, and in one patient, the boundary between the lesion and the left lobe of the liver was unclear, with low attenuation in the right lobe of the liver with circular enhancement. The remaining two patients showed no evidence of metastasis. CONCLUSION: Although GSC is extremely rare, it should be considered in the differential diagnosis of gastric adenocarcinoma and lymphoma. CT findings, combined with patient age and sex, can provide support for the diagnosis of GSC. However, the final diagnosis must be confirmed with histopathology.

RSC Adv ; 9(17): 9770-9776, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35520709


A new and efficient one-pot strategy combining catalyst-free synthesis and iodine catalysis has been developed for the synthesis of dihydrofuropyrimidines and spirodihydrofuropyrimidine pyrazolones. This approach affords products in moderate to high yields (up to 96%) with excellent diastereoselectivities (up to >25 : 1 dr). The reaction is simple to carry out and is metal-free.

RSC Adv ; 8(6): 3095-3098, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35541173


A catalytic asymmetric method for the synthesis of polysubstituted chromans via an oxa-Michael-nitro-Michael reaction has been developed. The squaramide-catalyzed domino reaction of 2-hydroxynitrostyrenes with trans-ß-nitroolefins produced chiral chromans with excellent enantioselectivities (up to 99% ee), diastereoselectivities (up to >20 : 1 dr), and moderate to good yields (up to 82%).

Org Biomol Chem ; 15(27): 5709-5718, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28650044


An asymmetric formal one-pot reaction of 4-hydroxycoumarins with unsaturated pyrazolones has been developed by merging a chiral bifunctional organocatalyst with molecular iodine, which furnished a series of optically active spiro[dihydrofurocoumarin/pyrazolone] heterocycles with spiro quaternary stereogenic centers in moderate to excellent yields (up to 99%) with excellent diastereoselectivities (up to >99 : 1 dr) and good to excellent enantioselectivities (up to 99% ee). The application in the gram-scale synthesis of chiral spiro[dihydrofurocoumarin/pyrazolone] compounds was also successfully realized.

Furocumarinas/síntese química , Pirazolonas/síntese química , Compostos de Espiro/síntese química , Ciclização , Furocumarinas/química , Estrutura Molecular , Pirazolonas/química , Compostos de Espiro/química
China Journal of Endoscopy ; (12): 73-76, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-664338


Objective To investigate the clinical value of endoscopic stent implantation combined with X-ray monitoring in the treatment of malignant gastroduodenal obstruction. Methods 70 cases of malignant obstruction of stomach and duodenum from January 2013 to December 2015 were enrolled. According to the patients' hospitalization sequence, the odd number of patients were enrolled in the study group, the even number of patients were enrolled in the control group, 35 cases in each. The difference is that the study group were performed in metallic stent placement under fluoroscopic monitoring and endoscopic direct vision, while the control group only under endoscopic direct vision. Record the operation time, the success rate and accuracy of disposable implantation, diseases, thedisplacement and falling of the stent, and complications. we statistically analyzed the data. Results The operation time of the intervention group on average was (9.71 ± 3.60) min, while the control group was (21.01 ± 5.20) min. The success rate and accuracy of disposable implantation of the intervention group was 97.14%, while the control group was 77.14%; After 4 weeks after stent patency rate were 97.14%, 74.28% in the control group; Two groups are with the same diseases. All of the patients had small amount of bleeding, which were stoped after treatment. There was no gastrointestinal ulcers, 1 case with stent displacement, 1 case with gastrointestinal complications, 1 case with metabolic complications in the intervention group. There was 4 cases with stent displacement, 6 cases with gastrointestinal complications, 7 case with metabolic complications the control group. Conclusion Gastroscope-X-ray combined with metallic stent implantation in the treatment of malignant gastroduodenal obstruction, short operation time, high success rate, stent implantation of accurate positioning, less complications, long survival, is a kind of method is simple and feasible, safe and effective.