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1.
Food Chem ; 452: 139606, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-38744127

ABSTRACT

In this study, two pectic polysaccharides (PFP-T and PFP-UM) were extracted from fresh passion fruit peels using three-phase partitioning (TPP) and sequential ultrasound-microwave-assisted TPP methods, respectively, and their effects on the in vitro gastrointestinal digestion and fecal fermentation characteristics were examined. The results indicate that gastrointestinal digestion has a minimal effect on the physicochemical and structural characteristics of PFP-T and PFP-UM. However, during in vitro fecal fermentation, both undigested PFP-T and PFP-UM are significantly degraded and utilized by intestinal microorganisms, showing increased the total relative abundance of Firmicutes and Bacteroidota in the intestinal flora. Notably, compared with PFP-UM, PFP-T better promoted the reproduction of beneficial bacteria such as Prevotella, Megasphaera and Dialister, while suppressed the growth of harmful genera including Escherichia-Shigella, producing higher content of short-chain fatty acids. Therefore, our findings suggest that PFP-T derived from passion fruit peel has potential as a dietary supplement for promoting intestinal health.


Subject(s)
Bacteria , Digestion , Fermentation , Fruit , Passiflora , Passiflora/chemistry , Passiflora/metabolism , Fruit/chemistry , Fruit/metabolism , Bacteria/metabolism , Humans , Polysaccharides/metabolism , Polysaccharides/chemistry , Pectins/metabolism , Pectins/chemistry , Feces/microbiology , Feces/chemistry , Gastrointestinal Microbiome , Plant Extracts/chemistry , Plant Extracts/metabolism , Models, Biological
2.
J Agric Food Chem ; 72(19): 10753-10771, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38706131

ABSTRACT

Food-borne biotoxins from microbes, plants, or animals contaminate unclean, spoiled, and rotten foods, posing significant health risks. Neutralizing such toxins is vital for human health, especially after food poisoning. Nanobodies (Nbs), a type of single-domain antibodies derived from the genetic cloning of a variable domain of heavy chain antibodies (VHHs) in camels, offer unique advantages in toxin neutralization. Their small size, high stability, and precise binding enable effective neutralization. The use of Nbs in neutralizing food-borne biotoxins offers numerous benefits, and their genetic malleability allows tailored optimization for diverse toxins. As nanotechnology continues to evolve and improve, Nbs are poised to become increasingly efficient and safer tools for toxin neutralization, playing a pivotal role in safeguarding human health and environmental safety. This review not only highlights the efficacy of these agents in neutralizing toxins but also proposes innovative solutions to address their current challenges. It lays a solid foundation for their further development in this crucial field and propels their commercial application, thereby contributing significantly to advancements in this domain.


Subject(s)
Single-Domain Antibodies , Animals , Single-Domain Antibodies/immunology , Single-Domain Antibodies/chemistry , Single-Domain Antibodies/genetics , Humans , Food Contamination/analysis , Food Contamination/prevention & control , Antibodies, Neutralizing/immunology , Toxins, Biological/immunology , Foodborne Diseases/prevention & control , Foodborne Diseases/immunology , Camelus/immunology
3.
Org Biomol Chem ; 22(16): 3215-3219, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38567548

ABSTRACT

Enabled by triethyl amine (Et3N) and thionyl chloride (SOCl2), an efficient and practical protocol for deoxygenation of sulfoxide to sulfide was developed. This new method features a wide range of substrate scope, including diaryl, dialkyl and aryl alkyl substituted sulfoxides. Detailed mechanistic investigations reveal the crucial role played by Et3N as an electron-donating reductant rather than a hydrogen-atom donor.

4.
Org Lett ; 26(7): 1399-1404, 2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38345406

ABSTRACT

The elusive nature of noncovalent π-interactions leads to their infrequent use as a design element in challenging chemical reactions. Stereocontrolling models based on coordinated noncovalent π-interactions were used for the asymmetric dihydroxylation of 1,1-disubstituted aliphatic alkenes. By introduction of a substituted phthalazine ring into the alkene substrates, the enantioselectivity reached 99% under the catalysis of bis-cinchona alkaloid ligands. Density functional theory calculations indicated a well-orchestrated, π-π interaction-directed "sandwich-like" transition state.

5.
Zhonghua Nan Ke Xue ; 29(4): 342-347, 2023 Apr.
Article in Chinese | MEDLINE | ID: mdl-38598219

ABSTRACT

OBJECTIVE: To evaluate the clinical effect of the traditional Chinese medicine (TCM) Tonglong Kaibi Prescription (TKP) in the treatment of severe BPH with kidney deficiency and blood stasis combined with damp heat syndrome. METHODS: We randomly divided 120 cases of severe BPH with kidney deficiency and blood stasis combined with damp heat syndrome into three groups of equal number, treated with TKP, doxazosin mesylate sustained-release tablets (the DM control), and TKP + DM, all for 8 weeks. We obtained the IPSS, TCM symptoms scores, quality of life (QOL) scores, maximum urinary flow rate (Qmax) and postvoid residual urine volume (PVR) from the patients before and after treatment and compared them among the three groups. RESULTS: After 8 weeks of treatment, the effectiveness rate was significantly higher in the TKP + DM than in the DM control group (P < 0.05). The IPSS, TCM symptoms scores, QOL scores and PVR decreased (P < 0.01), while the Qmax increased dramatically (P < 0.01) in all the three groups. Pairwise comparison showed that the IPSS and QOL scores were lower in the TKP + DM than in the TKP and DM control groups (P < 0.05 or 0.01), and so were the TCM syndrome scores in the TKP + DM and TKP groups than in the DM control (P < 0.01). There were no statistically significant differences in PVR and Qmax among the three groups after treatment (P> 0.05), and no serious adverse events during the treatment. CONCLUSION: TKP is safe and effective in the treatment of severe BPH, which can improve the TCM symptoms, reduce the IPSS, QOL scores and PVR and increase the Qmax of the patients. TKP is evidently superior to DM alone in improving TCM symptoms of BPH and combined medication of TKP and DM produces even better clinical efficacy.


Subject(s)
Prostatic Hyperplasia , Quality of Life , Humans , Male , Hyperplasia , Prescriptions , Prostate , Prostatic Hyperplasia/drug therapy , Syndrome
6.
Nat Commun ; 13(1): 3276, 2022 06 07.
Article in English | MEDLINE | ID: mdl-35672365

ABSTRACT

Molecular recognition and self-assembly are often mediated by intermolecular forces involving aromatic π-systems. Despite the ubiquity of such interactions in biological systems and in the design of functional materials, the elusive nature of aromatic π interaction results in that they have been seldom used as a design element for promoting challenging chemical reactions. Described here is a well-engineered catalytic system into which non-covalent π interactions are directly incorporated. Enabled by a lone pair-π interaction and a π-π stacking interaction operating collectively, efficient chiral recognition is successfully achieved in the long-pursued dihydroxylation-based kinetic resolution. Density functional theory calculations shed light on the crucial role played by the lone pair-π interaction between the carbonyl oxygen of the cinchona alkaloid ligand and the electron-deficient phthalazine π moiety of the substrate in the stereoselectivity-determining transition states. This discovery serves as a proof-of-principle example showing how the weak non-covalent π interactions, if ingeniously designed, could be a powerful guide in attaining highly enantioselective catalysis.


Subject(s)
Electrons , Oxygen , Catalysis , Oxygen/chemistry
7.
Zhonghua Nan Ke Xue ; 28(12): 1113-1118, 2022 Dec.
Article in Chinese | MEDLINE | ID: mdl-37846632

ABSTRACT

OBJECTIVE: To investigate the effect of pricking-reinforcing -reducing therapy (PRRT) on the semen quality and seminal plasma biochemical indexes of varicocele (VC) infertility patients. METHODS: We randomly and equally assigned 160 patients with VC infertility into a PRRT and a control group, the former treated by PRRT and the latter with oral ShengjingCapsules. Before and after treatment, we obtained the semen parameters, sperm morphology, sperm survival rate, sperm acrosin activity, seminal plasma neutral α glucosidase and seminal plasma zinc in the patients and compared them between the two groups. RESULTS: Before treatment, there were no statistically significant differences between the PRRT and control groups in sperm concentration (ï¼»16.81 ± 7.83ï¼½ vs ï¼»16.80 ± 7.54ï¼½ ×106 /ml, P > 0.05), total sperm count (ï¼»42.01 ± 19.57ï¼½ vs ï¼»41.99 ± 18.84ï¼½ ×106, P > 0.05), percentages of progressively motile sperm (PMS) (ï¼»15.37 ± 11.03ï¼½% vs ï¼»14.68 ± 10.27ï¼½%, P > 0.05) and morphologically normal sperm ( MNS) (1.62 ± 1.51ï¼½% vs ï¼»1.62 ± 1.13ï¼½%, P > 0.05), sperm survival rate (ï¼»28.11 ± 18.95ï¼½% vs ï¼»28.23±18.38ï¼½%, P > 0.05) and sperm acrosin activity (ï¼»28.11 ± 14.64ï¼½ vs ï¼»27.19 ± 14.07ï¼½ U/L, P > 0.05). After three months of treatment, all the patients showed evident increases in the above parameters (P < 0.05), even higher in the PRRT than in the control group, more significantly in sperm concentration (ï¼»38.88 ± 30.54ï¼½ vs ï¼»25.60 ± 14.71ï¼½ ×106 /ml, P < 0.05), PMS (ï¼»32.60 ± 12.46ï¼½% vs ï¼»27.67 ± 12.27ï¼½%, P < 0.05) and sperm acrosin activity (ï¼»65.74±31.81ï¼½ vs ï¼»67.94±17.95ï¼½ U/L, P < 0.05), though not significantly in total sperm count (97.20 ± 76.35ï¼½ vs ï¼»88.19 ± 39.56ï¼½ ×106, P > 0.05), MNS (ï¼»2.35 ± 1.83ï¼½% vs ï¼»1.87 ± 1.20ï¼½%, P > 0.05) and sperm survival rate (ï¼»61.44 ± 20.02ï¼½% vs ï¼»59.12 ± 22.48ï¼½%, P > 0.05). Compared with the baseline, after treatment, the patients in the PRRT group also exhibited elevated levels of neutral α-glucosidase (ï¼»14.42 ± 5.90ï¼½ vs ï¼»28.43 ± 19.76ï¼½ U/L, P < 0.05) and seminal plasma zinc (ï¼»2.11 ± 1.22ï¼½ vs ï¼»2.89 ± 1.23ï¼½ mmol/L, P < 0.05), and so did the controls (ï¼»14.44 ± 5.61ï¼½ vs ï¼»26.66 ± 17.69ï¼½ U/L , P < 0.05) and (ï¼»2.09 ± 1.10ï¼½ vs ï¼»2.82±1.08ï¼½ mmol/L, P < 0.05). No statistically significant difference, however, was observed between the two groups after treatment (P > 0.05). CONCLUSION: PRRT can significantly improve semen quality in patients with VC infertility, even more effective than ShengjingCapsules in improving sperm concentration, PMS, sperm survival rate, and sperm acrosin activity, which may be related to its effect of elevating the levels of seminal plasma neutral-α glucosidase and zinc providing sufficient energy for basic sperm metabolism, maturation, energy acquisition and motility.


Subject(s)
Infertility, Male , Varicocele , Humans , Male , Semen Analysis , Semen/metabolism , Infertility, Male/etiology , Infertility, Male/metabolism , Varicocele/complications , Varicocele/therapy , Varicocele/metabolism , Acrosin/metabolism , Sperm Count , Spermatozoa , Zinc , Sperm Motility
8.
Zhonghua Nan Ke Xue ; 28(6): 489-494, 2022 Jun.
Article in Chinese | MEDLINE | ID: mdl-37477464

ABSTRACT

OBJECTIVE: To compared the traditional Chinese medicine Danhong Tongjing Prescription (DTP) and microsurgery in the treatment of varicocele (VC)-induced infertility and investigate the factors influencing the recovery of semen parameters of the patients. METHODS: We retrospectively analyzed the clinical data on 218 cases of VC-induced infertility with qi-deficiency and blood-stasis treated with DTP (n = 86) or by microsurgery (n = 132) in our hospital from January 2017 to July 2019, and compared the semen parameters between the two groups of patients after treatment. With age, course of disease, degree of VC, change of the testis volume, estrogen/testosterone (E/T) ratio and levels of FSH and LH as independent variables, and increased semen parameters after treatment as dependent variables, we constructed a multivariate linear regression model and identified statistically significant independent variables. RESULTS: After treatment, sperm concentration and the percentages of progressively motile sperm (PMS) and morphologically normal sperm (MNS) were obviously improved in both the DTP and microsurgery groups, with statistically significant difference between the two groups in sperm concentration and MNS, but not in PMS. Linear regression analysis showed that the severity of VC was an influencing factor for the recovery of sperm concentration after treatment in the DTP group (r = -11.599, Ra2 = 0.044 9) and the course of VC infertility was a factor affecting the recovery of sperm count in the microsurgery group (r = -1.837, Ra2 = 0.035 7). CONCLUSION: DTP is comparable to microsurgery in improving sperm motility while microsurgery is more effective in increasing the percentage of MNS in the treatment of VC-induced infertility. Early surgery is recommended for the treatment of infertility induced by severe bilateral VC, and DTP can be selected for infertility caused by mild or moderate bilateral VC if the patient is unwilling to accept surgery or microsurgery is inaccessible in the hospital.


Subject(s)
Infertility, Male , Varicocele , Humans , Male , Varicocele/complications , Varicocele/surgery , Infertility, Male/etiology , Infertility, Male/surgery , Retrospective Studies , Semen , Microsurgery/adverse effects , Sperm Motility , Sperm Count , Multivariate Analysis
9.
Zhonghua Nan Ke Xue ; 28(7): 622-627, 2022 Jul.
Article in Chinese | MEDLINE | ID: mdl-37556221

ABSTRACT

OBJECTIVE: To investigate the therapeutic effect of magnetic resonance and magnetoelectric therapy (MRMT) combined with oral Danhong Tongjing Prescription (DTP) on chronic prostatitis / chronic pelvic pain syndrome (CP/CPPS) and the changes in the levels of cytokine-secretory IgA (sIgA), vascular cell adhesion molecule-1 (VCAM-1) and interleukin-8 (IL-8) after treatment. METHODS: Totally 200 patients with CP/CPPS of the qi stagnation and blood stasis type were randomly divided into three groups to receive MRMT + DTP (n = 68), MRMT (n = 67) and DTP (n = 65), respectively, all for 12 weeks. After treatment, we compared the total effectiveness rate, patients' scores on NIH-CPSI and traditional Chinese medicine (TCM) syndrome, and the expressions of sIgA, VCAM-1 and IL-8 in the EPS among the three groups of the patients. RESULTS: After treatment, the patients in the MRMT + DTP group, compared with those in the MRMT and DTP groups, showed a significantly higher total effectiveness rate (86.76% vs 79.10% and 78.46%, P < 0.05 and P < 0.01) and lower scores on pain or discomfort (4.61 ± 2.37 vs 5.86 ± 3.26 and 6.94 ± 2.25 P < 0.01), abnormal urination symptoms (2.98 ± 1.75 vs 3.85 ± 2.01 and 3.94 ± 1.95) and quality of life (3.26 ± 1.87 vs 4.54 ± 2.13 and 4.69 ± 1.72). There were statistically significant differences in the total NIH-CPSI scores among the three groups (10.64 ± 5.91 vs 4.59 ± 6.87 vs 15.54 ± 5.76, P < 0.05). The MRMT + DTP group also exhibited a remarkably lower TCM syndrome score than the MRMT and DTP groups (5.56 ± 3.42 vs 7.37 ± 4.57 and 8.16 ± 3.65, P < 0.05). Compared with the baseline, the expressions sIgA, VCAM-1 and IL8 were all markedly decreased after treatment in the MRMT + DTP (Z = -7.170, Z = -7.182, Z = -7.18), MRMT (Z = -6.802, Z = -6.973, Z = -6.768) and DTP groups (Z = -5.963, Z = -6.990 Z = -5.618) (P < 0.05), even more significantly in the former than in the latter two groups (P < 0.05). CONCLUSION: Magnetic resonance and magnetoelectric therapy combined with Danhong Tongjing Prescription has a good therapeutic effect on CP/CPPS of the qi stagnation and blood stasis type, probably by regulating sIgA, VCAM-1, IL-8 and other cytokines, activating the function of the immune system, inhibiting inflammation, and promoting the absorption of local inflammatory substances.


Subject(s)
Interleukin-8 , Prostatitis , Male , Humans , Chronic Disease , Vascular Cell Adhesion Molecule-1/therapeutic use , Quality of Life , Pelvic Pain/therapy , Prostatitis/drug therapy , Magnetic Resonance Spectroscopy
10.
Angew Chem Int Ed Engl ; 61(3): e202112993, 2022 01 17.
Article in English | MEDLINE | ID: mdl-34626073

ABSTRACT

The mechanistic uniqueness and versatility of borrowing hydrogen catalysis provides an opportunity to investigate the controllability of a cascade reaction, and more importantly, to realize either one or both of chiral recognition and chiral induction simultaneously. Here we report that, in a borrowing hydrogen cascade starting from racemic allylic alcohols, one of the enantiomers could be kinetically resolved, while the other enantiomer could be purposely converted to various targeted products, including α,ß-unsaturated ketones, ß-functionalized ketones and γ-functionalized alcohols. By employing a robust Ru-catalyst, both kinetic resolution and asymmetric induction were achieved with remarkable levels of efficiency and enantioselectivity. Density functional theory (DFT) calculations suggest that corresponding catalyst-substrate π-π interactions are pivotal to realize the observed stereochemical diversity.

11.
Molecules ; 26(24)2021 Dec 10.
Article in English | MEDLINE | ID: mdl-34946557

ABSTRACT

No matter through asymmetric reduction of ketones or kinetic resolution of secondary alcohols, enantioselective synthesis of the corresponding secondary alcohols is challenging when the two groups attached to the prochiral or chiral centers are spatially or electronically similar. For examples, dialkyl (sp3 vs. sp3), diaryl (sp2 vs. sp2), and aryl-alkenyl (sp2 vs. sp2) alcohols are difficult to produce with high enantioselectivities. By exploiting our recently developed Ru-catalysts of minimal stereogenicity, we reported herein a highly efficient kinetic resolution of aryl-alkenyl alcohols through hydrogen transfer. This method enabled such versatile chiral building blocks for organic synthesis as allylic alcohols, to be readily accessed with excellent enantiomeric excesses at practically useful conversions.

12.
J Agric Food Chem ; 69(35): 10151-10162, 2021 Sep 08.
Article in English | MEDLINE | ID: mdl-34432454

ABSTRACT

Inflammatory bowel disease (IBD) is a disease characterized by intestinal inflammation with immune dysregulation and intestinal microecological imbalance. In a dextran sulfate sodium salt (DSS)-induced IBD mouse model, noni (Morinda citrifolia L.) fruit polysaccharides (NFP) with homogalacturonan and rhamnogalacturonan-I domain decreased the concentration of serum LPS, TNF-α, and IL-17 by 84, 42, and 65%, respectively. It was abolished when intestinal microbiota were depleted by antibiotics. Sequencing analysis of gut microbiota showed an attenuated disruption of the microbial composition in the DSS+NFP group. Targeted metabolomic analysis revealed that NFP upregulated the content of acetic acid, propionic acid, and butyric acid by onefold but reduced isobutyric acid and isovaleric acid contents. NFP also inhibited JNK, ERK, and NF-κB phosphorylation of IBD mice. Taken together, the mechanism of NFP alleviating IBD is related to the intestinal microecological balance to inhibit inflammatory signaling pathways. This study provides a basis for NFP as a cheap intervention for the prevention and treatment of IBD patients.


Subject(s)
Gastrointestinal Microbiome , Inflammatory Bowel Diseases , Morinda , Animals , Dextran Sulfate , Fruit , Humans , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/genetics , Mice , NF-kappa B/genetics , Polysaccharides
13.
Chinese Medical Journal ; (24): 2066-2072, 2021.
Article in English | WPRIM (Western Pacific) | ID: wpr-887661

ABSTRACT

BACKGROUND@#The mortality rate among patients with nasopharyngeal carcinoma (NPC) has improved significantly with the advent of chemoradiotherapy strategies. However, distant metastasis remains problematic. Tumor-specific reactivity in cancer patients has been detected exclusively in CD39+ T cells, particularly in CD39+CD103+ T cells. Circulating cancer-specific T cells are important for protecting against metastasis. This study aimed to evaluate the predictive value of circulating CD39+CD8+ T cells for metastasis in patients with NPC.@*METHODS@#We performed a cross-sectional, longitudinal study of 55 patients with newly diagnosed NPC of stage III-IVa. All patients were initially treated with standard combined chemoradiotherapy. Blood samples were obtained from 24 patients before and at 1 month and 6 months after treatment. T cell expression of CD39 and CD103, together with the markers of T cell exhaustion programmed death-1 (PD-1)/T cell immunoglobulin and mucin domain-containing protein 3 (Tim-3) and markers of cell differentiation CD27/CC-chemokine receptor 7/CD45RA, was examined by flow cytometry. The Wilcoxon rank-sum test analysis was used to analyze the differences between two groups. Kaplan-Meier analysis was used for analysis of progression-free survival (PFS).@*RESULTS@#The expression of circulating CD39+CD8+ and CD39+CD103+ CD8+ T cells was significantly higher in patients without distant metastasis (CD39+CD8+: 6.52% [1.24%, 12.58%] vs. 2.41% [0.58%, 5.31%], Z=-2.073, P=0.038 and CD39+CD103+CD8+: 0.72% [0.26%, 2.05%] vs. 0.26% [0.12%, 0.64%], Z=-2.313, P = 0.021). Most CD39+ T cells did not express PD-1 or Tim-3. Patients with high expression of CD39+CD103+CD8+ T cells had better PFS than patients with low expression (log rank value = 4.854, P = 0.028). CD39+CD8+ T cells were significantly elevated at 1-month post-treatment (10.02% [0.98%, 17.42%] vs. 5.91% [0.61%, 10.23%], Z = -2.943, P = 0.003). The percentage of advanced differentiated CD8+ T cells also increased at 1-month post-treatment compared with pre-treatment (33.10% [21.60%, 43.05%] vs. 21.00% [11.65%, 43.00%], Z = -2.155, P = 0.031). There was a significant correlation between elevated CD39+CD8+ T cells and increased effector memory T cells (intermediate stage: r = 0.469, P = 0.031; advanced stage: r = 0.508, P = 0.019).@*CONCLUSIONS@#CD39+CD8+ circulating T cells have preserved effector function, contributing to an improved prognosis and a reduced risk of metastasis among NPC patients. These cells may thus be a useful predictive marker for a better prognosis in patients with NPC.


Subject(s)
Humans , CD8-Positive T-Lymphocytes , Chemoradiotherapy , Cross-Sectional Studies , Longitudinal Studies , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/therapy , Prognosis
14.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-876170

ABSTRACT

Objective:To characterize the mortality rate of residents in Minhang District of Shanghai from January to April in 2016-2020, and to determine the change in the epidemic Coronavirus Disease 2019 (COVID-19) in 2020. Methods:Data of mortality surveillance was collected from the death registry of Shanghai residents. Cause of death was coded and classified per the International Classification of Diseases (ICD-10). The standardized mortality rate was calculated based on the standard population of China in 1990. The analysis was performed by Excel 2016 and SPSS 20.0. Results:From 2016 to 2020, the average crude mortality rate of residents was 281.75/100 000 from January to April in Minhang District of Shanghai, and the standardized mortality rate was 66.57/100 000. The top five causes of death in the latest five years were cardiovascular diseases, tumor, respiratory diseases, endocrine diseases, and injury and poisoning. The mortality rate was the lowest from January to April in 2020 in the past five years; furthermore, the mortality rate of respiratory system diseases has decreased significantly. Conclusion:Sex, age, place and causes of death in residents are consistent from January to April across years in Minhang District of Shanghai. However, there are minor differences in 2020, which may be attributable to the epidemic of COVID-19.

15.
Org Lett ; 22(18): 7278-7283, 2020 09 18.
Article in English | MEDLINE | ID: mdl-32896129

ABSTRACT

The borrowing-hydrogen (or hydrogen autotransfer) process, where the catalyst dehydrogenates a substrate and formally transfers the H atom to an unsaturated intermediate, is an atom-efficient and environmentally benign transformation. Described here is an example of an asymmetric borrowing-hydrogen cascade for the formal anti-Markovnikov hydroamination of allyl alcohols to synthesize optically enriched γ-secondary amino alcohols. By exploiting the Ru-(S)-iPrPyme catalyst with minimal stereogenicity, a cascade process including dehydrogenation, conjugate addition, and asymmetric reduction was developed. The mild conditions, functional group tolerance, and broad substrate scope (54 examples) demonstrate the synthetic practicality of the catalytic system.

16.
Chem Commun (Camb) ; 56(72): 10552-10555, 2020 Sep 10.
Article in English | MEDLINE | ID: mdl-32785314

ABSTRACT

A multicomponent catalytic reaction between ketones, Morita-Baylis-Hillman (MBH) carbonates and trifluoromethylthiolating agents is devised for straightforwardly accessing two products, α-trifluoromethylthiolated ketones and α-methylene ß-amino esters in a one pot fashion. Particularly noteworthy is that the trifluoromethylthiolating reagent is employed as both the nitrogen and SCF3 source initiated by DABCO. This mild one pot strategy enjoys atom- and step-economic attractiveness, for direct introduction of an SCF3 group onto a variety of acyclic ketones, which have been considered as less effective and less developed substrates.

17.
Chem Commun (Camb) ; 54(36): 4581-4584, 2018 May 01.
Article in English | MEDLINE | ID: mdl-29667658

ABSTRACT

Although recent progress has been made in introducing an SCF3 functionality into a variety of molecules, enantioselective trifluoromethylthiolation remains challenging, especially the α-trifluoromethylthiolation of carbonyl compounds. The present study describes a diastereo and enantioselective Cu-catalyzed tandem 1,4-addition/trifluoromethylthiolation of acyclic enones. The tandem reaction enables the asymmetric integration of the -SCF3 group to carbonyl compounds, establishing chiral tertiary α-carbon centers and affording α-SCF3-ß-substituted carbonyl compounds in 50-92% yields with up to 20 : 1 dr and 96% ee.

18.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-789449

ABSTRACT

Objective To analyze the change in cost reduction for tuberculosis (TB) patients in Tilanqiao community of Shanghai from 2006 to 2016,and to evaluate the implement effect of TB remission policy in Shanghai.Methods The data were collected on treatment costs for 309 TB patients who had completed treatment and participated in the cost remission reimbursement by outpatient registration.The trend of deductible expenses and the remission costs were analyzed by SPSS.Results During the implementation of the original remission policy(ORP),the deductible expense was 1 021.06±457.67 yuan.And it changed to 2 320.64±1 544.73yuan under the new remission policy (NRP),which had an increase of 1.27 times and the new remission fee ratio was 45.19%.The deductible expenses change curve shown a trend of rising.The new remission fee ratio was 27.62% in 2009 and increased to 46.62% in 2010,then became 51.05% in 2016.The new remission fee ratio for outpatients was significantly lower than that for the hospitalized.During the implementation of the ORP,the remission cost was 931.05±465.47 yuan,and it was 1 507.80±974.15 of the NRP,which increased 61.95%.The remission ratio was 17.55% of the ORP,when it was 15.91% of the NRP which decreased by 1.64 percent.The remission ratio curve showed a trend of downward.The remission ratio for outpatients was significantly higher than that for the hospitalized.Conclusion From 2006 to 2016,the implement effect of remission policy on treatment costs of tuberculosis had improved.However,it had not effectively reduced the disease burden of TB patients.So in the follow-up remission policy,we must strengthen improvement on the settings of deductible project and control disease treatment.

19.
Org Lett ; 18(19): 4986-4989, 2016 10 07.
Article in English | MEDLINE | ID: mdl-27667117

ABSTRACT

A highly efficient asymmetric synthesis of chiral thioflavanones is developed via conjugate addition of arylzinc reagents to thiochromones using Rh(COD)Cl2/(R)-3,4,5-MeO-MeOBIPHEP catalyst. This method overcomes catalyst poisoning and substrate inertness and affords a series of chiral thioflavanones (2-arylthiochroman-4-ones) in good yields (up to 91% yield) with excellent ee values (up to 97% ee). The established asymmetric synthesis paves the way for further pharmaceutical studies.

20.
Org Biomol Chem ; 14(34): 8088-91, 2016 Sep 14.
Article in English | MEDLINE | ID: mdl-27503764

ABSTRACT

Bismuth triflate (Bi(OTf)3) is identified as an efficient catalyst for the direct addition of isocyanides to 2H-chromene acetals. The large scope of isocyanides and chromene acetals makes them suitable substrates in this catalytic system. By this synthetic strategy, a polyfunctional molecular scaffold, 2-carboxamide-2H-chromenes could be prepared efficiently in one step up to 95% yield. In addition, this efficient and practical protocol proceeded smoothly in the gram scale even when the catalytic loading was reduced to 2 mol%.

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