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1.
Chem Commun (Camb) ; 60(27): 3717-3720, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38481359

ABSTRACT

The effective and mild [4+1] annulation of ninhydrin-derived MBH carbonates with α,ß-unsaturated ketones has been developed, providing a wide range of multisubstituted furans in high yields (up to 90%) with excellent ß-regioselectivities. In contrast, the polysubstituted cyclopentenes bearing dispiro-bisindanedione motifs were obtained via classical [3+2] annulations by employing ninhydrin-derived MBH carbonates with 2-arylidene-1,3-indandiones under the same catalytic conditions. Furthermore, the structures of two kinds of cycloadducts were straightforwardly confirmed through X-ray diffraction analysis.

2.
Int J Surg ; 110(2): 1068-1078, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-37924501

ABSTRACT

AIM: This paper aimed to explore the application of three-dimensional (3D) printing in cardiovascular diseases, to reach an insight in this field and prospect the future trend. METHODS: The articles were selected from the Web of Science Core Collection database. Excel 2019, VOSviewer 1.6.16, and CiteSpace 6.1.R6 were used to analyze the information. RESULTS: A total of 467 papers of 3D printing in cardiovascular diseases were identified, and the first included literature appeared in 2000. A total of 692 institutions from 52 countries participated in the relevant research, while the United States of America contributed to 160 articles and were in a leading position. The most productive institution was Curtin University , and Zhonghua Sun who has posted the most articles ( n =8) was also from there. The Frontiers in Cardiovascular Medicine published most papers ( n =25). The Journal of Thoracic and Cardiovascular Surgery coveted the most citations ( n =520). Related topics of frontiers will still focus on congenital heart disease, valvular heart disease, and left atrial appendage closure. CONCLUSIONS: The authors summarized the publication information of the application of 3D printing in cardiovascular diseases related literature from 2000 to 2023, including country and institution of origin, authors, and publication journal. This study can reflect the current hotspots and novel directions for the application of 3D printing in cardiovascular diseases.


Subject(s)
Cardiovascular Diseases , Humans , Cardiovascular Diseases/surgery , Bibliometrics , Printing, Three-Dimensional , Databases, Factual , Health Facilities
3.
ACS Infect Dis ; 9(9): 1711-1729, 2023 09 08.
Article in English | MEDLINE | ID: mdl-37610012

ABSTRACT

A series of pleuromutilin derivatives containing an oxazolidinone skeleton were synthesized and evaluated in vitro and in vivo as antibacterial agents. Most of the synthesized derivatives exhibited potent antibacterial activities against three strains of Staphylococcus aureus (including MRSA ATCC 33591, MRSA ATCC 43300, and MSSA ATCC 29213) and two strains of Staphylococcus epidermidis (including MRSE ATCC 51625 and MSSE ATCC 12228). Compound 28 was the most active antibacterial agent in vitro (MIC = 0.008-0.125 µg·mL-1) and exhibited a significant bactericidal effect, low cytotoxicity, and weak inhibition (IC50 = 20.66 µmol·L-1) for CYP3A4, as well as exhibited less possibility to cause bacterial resistance. Furthermore, in vivo activities indicated that the compound was effective in reducing MRSA load in a murine thigh infection model. Moreover, it clearly facilitated the healing of MRSA skin infection and inhibited the secretion of the TNF-α, IL-6, and MCP-1 inflammatory factors in serum. These results suggest that oxazolidinone pleuromutilin is a promising therapeutic candidate for drug-resistant bacterial infections.


Subject(s)
Diterpenes , Oxazolidinones , Animals , Mice , Anti-Bacterial Agents/pharmacology , Oxazolidinones/pharmacology , Oxindoles , Pleuromutilins
4.
Food Chem ; 411: 135456, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-36669340

ABSTRACT

Oat supplementation of the ruminant diet can improve growth performance and meat quality traits, but the role of muscle metabolites has not been evaluated. This study aimed to establish whether oat grass supplementation (OS) of Small-tail Han sheep improved growth performance and muscle tissue metabolites that are associated with better meat quality and flavor. After 90-day, OS fed sheep had higher live-weight and carcass-weight, and lower carcass fat. Muscle metabolomics analysis showed that OS fed sheep had higher levels of taurine, l-carnitine, inosine-5'-monophospgate, cholic acid, and taurocholic acid, which are primarily involved in taurine and hypotaurine metabolism, purine metabolism, and bile acid biosynthesis and secretion, decreased fat accumulation and they promote functional or flavor metabolites. OS also increased muscle levels of amino acids that are attributed to better quality and flavorsome mutton. These findings provided further evidence for supplementing sheep with oat grass to improve growth performance and meat quality.


Subject(s)
Amino Acids , Avena , Sheep , Animals , Amino Acids/analysis , Avena/metabolism , Tail/chemistry , Tail/metabolism , Body Composition , Fatty Acids/analysis , Diet/veterinary , Muscles/metabolism , Meat/analysis , Dietary Supplements/analysis , Taurine/metabolism , Taurine/pharmacology , Animal Feed/analysis
5.
J Org Chem ; 88(1): 493-503, 2023 01 06.
Article in English | MEDLINE | ID: mdl-36550408

ABSTRACT

Spiroindolizidine oxindoles represent a kind of privileged scaffold in many biologically active natural alkaloids. 2,3-Dihydrobenzofuran derivatives exhibit significant bioactivities in a variety of pharmaceuticals. Herein, we assembled these two privileged fragments into a small molecule via double-dearomative [3 + 2] cycloadditions with pyridinium ylides and 2-nitrobenzofurans. This protocol features remarkable advantages including wide substrate scope, mild condition, high level of diastereoselectivities and yields. Thus, a collection of spiroindolizidine-fused dihydrobenzofurans/indolines were facilely produced efficiently.


Subject(s)
Alkaloids , Cycloaddition Reaction , Stereoisomerism , Catalysis , Alkaloids/chemistry , Cyclization
6.
Zhonghua Nan Ke Xue ; 27(9): 809-814, 2021 Sep.
Article in Chinese | MEDLINE | ID: mdl-34914257

ABSTRACT

OBJECTIVE: To analyze the composition of prostatic calculus in patients with BPH and explore its pathogenic factors and histopathological characteristics. METHODS: Strictly following the inclusion and exclusion criteria, we included in this retrospective study 580 cases of bipolar transurethral plasma kinetic prostatectomy (TUPKP) performed in our hospital from May 2015 to May 2019, analyzed the histopathological and calculus-composition features of the patients with BPH complicated by prostatic calculi (the BPH+PC group) and the histopathological data of those with BPH only (the BPH group). We compared the related factors between the two groups of patients and performed uni- and multivariate logistic regression analyses of the data on those in the BPH+PC group. RESULTS: The incidence rate of chronic inflammation was significantly higher in the BPH+PC than in the BPH group (83.1% vs 61.1%, P < 0.05), 90% of the cases moderate to severe and 81% with inflammatory cells mainly distributed in the prostate gland in the BPH+PC group, and 74% with inflammatory cells chiefly distributed in the prostate gland and stroma in the BPH group, with statistically significant difference between the two groups (P < 0.05). Prostatic calculi were found in 302 (52.1%) of the patients, including 71 cases of simple calculi (23.5%) and 231 cases of mixed calculi (76.5%). As for the chemical composition, calcium oxalate was detected in 212 cases (70.2%), carbonate apatite in 206 (68.2%), magnesium ammonium phosphate in 158 (52.3%), and uric acid calculi in 19 (6.3%). The calculus composition was not correlated with the age of the patients. There were statistically significant differences between the two groups of patients in age, prostate volume and IPSS (P < 0.05), but not in the PSA level, postvoid residual urine volume (PRV) or maximum urinary flow rate (Qmax) (P > 0.05). Logistic regression analyses showed that prostatic calculus was significantly correlated with chronic inflammation of the prostate, the patient's age and IPSS (P < 0.05) but not with the PSA level, PRV or Qmax (P > 0.05). CONCLUSIONS: Prostatic calculus has a high incidence in BPH patients and varies widely in composition, chiefly consisting of calcium oxalate and carbonate apatite. The major factors contributing to prostatic calculi include chronic inflammation of the prostate (primarily the severe type), age and BPH. Prostate calculi may aggravate lower urinary tract symptoms, especially urinary storage symptoms, in patients with BPH, but not significantly affect the PSA level.?.


Subject(s)
Calculi , Prostatic Hyperplasia , Humans , Retrospective Studies
7.
Zhongguo Zhong Yao Za Zhi ; 45(12): 2982-2991, 2020 Jun.
Article in Chinese | MEDLINE | ID: mdl-32627476

ABSTRACT

Dao-di herbs are an important part of clinical medicine in traditional Chinese medicine. They are also precious wealth left to human beings from history, which contain deep traditional Chinese cultural connotations and play an important role in supporting and serving the Chinese medicine business. The relevant policy documents introduced by various national ministries and commissions have many contents and requirements related to the promotion of Dao-di herbs protection and industrial development. Due to the Dao-di herbs industry has a series of characteristics, such as a long chain, many involved links, long cycles, multiple production entities, multiple locations, and various types, the high-quality development of the industry has put forward higher requirements on the linkage between upstream and downstream, production entities, traceability of the whole process and information sharing. This article takes Dao-di herbs certification work as an application scenario and entry point, and discusses it from the perspective of block chain and information technology. It proposes the following work ideas: establish multi-party consensus from the macro-organizational management, business, and operational technical levels, and unblock channels for data and information, to achieve institutionalization of certification; establish certification-related standards and specifications to achieve certification standardization; build a certification hardware system to achieve certification networking; build a certification software system to develop functions for specific information content such as identity, origin, production, production process, quality, product and brand of authentic medicinal material production interactively, and realize certification programmatic; data security and sharing of related production activities to achieve socialization of certification. Make full use of modern technologies such as blockchain, the internet of things, big data and information technology, and through the joint participation of management, production, use and the public, the whole process information of Daodi herbs is integrated to form an interconnected information sharing application mode, thus, to serve and promote the high-quality development of Dao-di herbs industry.


Subject(s)
Drugs, Chinese Herbal , Plants, Medicinal , Blockchain , Humans , Medicine, Chinese Traditional , Technology
8.
Article in English | MEDLINE | ID: mdl-32117815

ABSTRACT

Bacterial infection remains one of the leading causes of death worldwide due to the continuous rise of multiple antibiotic-resistant bacteria. Focusing solely on bacteria as the drug targets is a major limitation inherent in the conventional antibiotic therapy. Recently, host-directed therapies have become such an innovative approach to modulate the host defense system and the interplay of innate and adaptive immunity. Our previous studies showed that memantine (MEM), an α7 nAChR antagonist, could efficiently block multi-drug resistant Escherichia coli-caused bacteremia and meningitis in a mouse model. However, the underlying mechanisms that govern the antibacterial effects of MEM are still unknown. In this study, we demonstrated that MEM is able to significantly suppress E. coli infection by enhancing E. coli-induced formation and release of NETs in vitro and in vivo. MEM could promote the trapping and bactericidal activities of the polymorphonuclear neutrophils (PMNs) in a manner dependent on α7 nAChR, since knockdown of this receptor noticeably reduces the survival ability of bacteria in PMNs while MEM no longer affects the survival of bacteria in PMNs. Our results also showed that when the expression of S100A9, an antiseptic protein, is inhibited, pathogen survival rates in PMNs increase significantly. MEM reverses this effect in a concentration-dependent manner. MEM stimulates the production of MPO, S100A9, and DNA in PMNs and accelerates the release of depolymerized chromatin fibers into the extracellular space, suggesting the formation of NETs. Taken together, our data suggest that MEM effectively blocks bacterial infection through the promotion of the antibacterial function of NETs induced by E. coli.


Subject(s)
Extracellular Traps , Meningitis , Animals , Escherichia coli , Memantine/pharmacology , Mice , Neutrophils
9.
Cell Biol Toxicol ; 36(5): 399-416, 2020 10.
Article in English | MEDLINE | ID: mdl-32002708

ABSTRACT

Androgen deprivation therapy (ADT) via surgical or chemical castration frequently fails to halt lethal castration-resistant prostate cancer (CRPC), which is induced by multiple mechanisms involving constitutive androgen receptor (AR) splice variants, AR mutation, and/or de novo androgen synthesis. The AR N-terminal domain (NTD) possesses most transcriptional activity and is proposed as a potential target for CRPC drug development. We constructed a screening system targeting AR-NTD transcription activity to screening a compound library and identified a novel small molecule compound named QW07. The function evaluation and mechanism investigation of QW07 were carried out in vitro and in vivo. QW07 bound to AR-NTD directly, blocked the transactivation of AR-NTD, blocked interactions between co-regulatory proteins and androgen response elements (AREs), inhibited the expression of genes downstream of AR, and inhibited prostate cancer growth in vitro and in vivo. QW07 was demonstrated as an AR-NTD-specific antagonist with the potential to inhibit both canonical and variant-mediated AR signaling to regress the CRPC xenografts and is proposed as a lead compound for a specific antagonist targeting AR-NTD.


Subject(s)
Prostatic Neoplasms, Castration-Resistant/drug therapy , Receptors, Androgen/chemistry , Receptors, Androgen/metabolism , Animals , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Male , Mice, Inbred BALB C , Mice, Nude , Prostatic Neoplasms, Castration-Resistant/genetics , Prostatic Neoplasms, Castration-Resistant/pathology , Protein Domains , Remission Induction , Response Elements/genetics , Transcription, Genetic/drug effects
10.
Microorganisms ; 7(9)2019 Sep 09.
Article in English | MEDLINE | ID: mdl-31505744

ABSTRACT

Pennisetum sinese is a good forage grass with high biomass production and crude proteins. However, little is known about the endophytic fungi diversity of P. sinese, which might play an important role in the plant's growth and biomass production. Here, we used high throughput sequencing of the Internal Transcribed Spacer (ITS) sequences based on primers ITS5-1737 and ITS2-2043R to investigate the endophytic fungi diversity of P. sinese roots at the maturity stage, as collected from four provinces (Shaanxi province, SX; Fujian province, FJ; the Xinjiang Uyghur autonomous prefecture, XJ and Inner Mongolia, including sand (NS) and saline-alkali land (NY), China). The ITS sequences were processed using QIIME and R software. A total of 374,875 effective tags were obtained, and 708 operational taxonomic units (OTUs) were yielded with 97% identity in the five samples. Ascomycota and Basidiomycota were the two dominant phyla in the five samples, and the genera Khuskia and Heydenia were the most abundant in the FJ and XJ samples, respectively, while the most abundant tags in the other three samples could not be annotated at the genus level. In addition, our study revealed that the FJ sample possessed the highest OTU numbers (242) and the NS sample had the lowest (86). Moreover, only 22 OTUs were present in all samples simultaneously. The beta diversity analysis suggested a division of two endophytic fungi groups: the FJ sample from the south of China and the other four samples from north or northwest China. Correlation analysis between the environmental factors and endophytic fungi at the class level revealed that Sordariomycetes and Pucciniomycetes had extremely significant positive correlations with the total carbon, annual average precipitation, and annual average temperature, while Leotiomycetes showed an extremely significant negative correlation with quick acting potassium. The results revealed significant differences in the root endophytic fungi diversity of P. sinese in different provinces and might be useful for growth promotion and biomass production in the future.

11.
Int J Biol Macromol ; 137: 1013-1019, 2019 Sep 15.
Article in English | MEDLINE | ID: mdl-31299251

ABSTRACT

Photophobic (white) films were prepared by mixing hydroxypropyl methylcellulose (HPMC) of different molecular weights with sodium citrate (SC). Wide angle X-ray diffractometry, small angle X-ray scattering, scanning electron microscopy, dynamic mechanical analysis, whiteness determination and texture analysis were used to investigate the effect of HPMC molecular weight on the aggregation structures and properties of HPMC film. The crystalline integrity decreased with the increased molecular weight of HPMC for these HPMC/SC films. Similar crystallinity was observed for 6HPMC/SC and 15HPMC/SC, which was larger than that of 50HPMC/SC. All the three HPMC/SC film showed surface fractal structure with similar Ds. With the increasing molecular weight of HPMC, the HPMC/SC film showed honeycomb structures with smaller holes and more compact porous structure, Tg first increased and then decreased a little, the tensile strength and elongation increased with the increasing HPMC molecular weight. 50HPMC/SC films with the smallest pores showed the largest whiteness. A new Tg' peak was observed for HPMC/SC film.


Subject(s)
Hypromellose Derivatives/chemistry , Light , Sodium Citrate/chemistry , Mechanical Phenomena , Molecular Weight
12.
Microorganisms ; 7(2)2019 Feb 11.
Article in English | MEDLINE | ID: mdl-30754647

ABSTRACT

Pennisetum sinese, a source of bio-energy with high biomass production, is a species that contains high crude protein and will be useful for solving the shortage of forage grass after the implementation of "Green for Grain" project in the Loess plateau of Northern Shaanxi in 1999. Plants may receive benefits from endophytic bacteria, such as the enhancement of plant growth or the reduction of plant stress. However, the composition of the endophytic bacterial community associated with the roots of P. sinese is poorly elucidated. In this study, P. sinese from five different samples (Shaanxi province, SX; Fujian province, FJ; the Xinjiang Uyghur autonomous prefecture, XJ and Inner Mongolia, including sand (NS) and saline-alkali land (NY), China) were investigated by high-throughput next-generation sequencing of the 16S rDNA V3-V4 hypervariable region of endophytic bacteria. A total of 313,044 effective sequences were obtained by sequencing five different samples, and 957 effective operational taxonomic units (OTUs) were yielded at 97% identity. The phylum Proteobacteria, the classes Gammaproteobacteria and Alphaproteobacteria, and the genera Pantoea, Pseudomonas, Burkholderia, Arthrobacter, Psychrobacter, and Neokomagataea were significantly dominant in the five samples. In addition, our results demonstrated that the Shaanxi province (SX) sample had the highest Shannon index values (3.795). We found that the SX (308.097) and NS (126.240) samples had the highest and lowest Chao1 richness estimator (Chao1) values, respectively. Venn graphs indicated that the five samples shared 39 common OTUs. Moreover, according to results of the canonical correlation analysis (CCA), soil total carbon, total nitrogen, effective phosphorus, and pH were the major contributing factors to the difference in the overall composition of the bacteria community in this study. Our data provide insights into the endophytic bacteria community composition and structure of roots associated with P. sinese. These results might be useful for growth promotion in different samples, and some of the strains may have the potential to improve plant production in future studies.

13.
Steroids ; 140: 173-178, 2018 12.
Article in English | MEDLINE | ID: mdl-30389306

ABSTRACT

A novel synthetic route of producing ursodeoxycholic acid (UDCA) and obeticholic acid (OCA) was developed through multiple reactions from cheap and readily-available cholic acid. The reaction conditions of the key elimination reaction of mesylate ester group were also investigated and optimized, including solvent, base and reaction temperature. In the straightforward synthetic route for preparation of UDCA and OCA, most of the reaction steps have high conversions with average yields of 94% and 92%, and overall yield up to 65% (7 steps) and 36% (11 steps) from cholic acid, respectively. This promising route offers economical and efficient strategies for potential large-scale production of UDCA and OCA.


Subject(s)
Chenodeoxycholic Acid/analogs & derivatives , Cholic Acid/chemistry , Ursodeoxycholic Acid/chemical synthesis , Chemistry Techniques, Synthetic , Chenodeoxycholic Acid/chemical synthesis , Chenodeoxycholic Acid/chemistry , Cost-Benefit Analysis , Ursodeoxycholic Acid/chemistry
14.
Zhonghua Nan Ke Xue ; 24(1): 45-49, 2018.
Article in Chinese | MEDLINE | ID: mdl-30157359

ABSTRACT

OBJECTIVE: To study the correlation of leukocyte subsets with sperm DNA damage in the semen of infertile men with asymptomatic genital tract infection (AGTI). METHODS: This study included 111 infertile males with AGTI. After routine semen analysis, we determined the concentration of CD45+ leukocytes in the semen by immunocytochemistry, measured the concentrations of CD14+ cells of the mononuclear / macrophagic system and activated macrophages and HLA-DR+ cells in the semen by flow cytometry, and examined the sperm DNA fragmentation index (DFI) and the expression of 8-hydroxy-2'-deoxyguanosine (8-OHdG) by TUNEL assay. Then we analyzed the correlation of seminal leukocyte subsets with sperm DNA damage and routine semen parameters. RESULTS: The concentration of CD45+ leukocytes was correlated significantly with those of CD14+ and HLA-DR+ cells in the semen (P <0.01), but not that of leukocyte subsets with routine semen parameters, sperm DFI, or the percentage of 8-OHdG-positive cells. The percentage of 8-OHdG-positive sperm was correlated positively with the sperm DFI (r = 0.48, P<0.01) but negatively with sperm concentration (r = -0.44, P <0.01). After adjusted for age, abstinence time and cigarette smoking, the percentage of 8-OHdG-positive sperm was correlated independently with sperm concentration (ß = -0.25, P = 0.008) and DFI (ß = 0.23, P = 0.05). CONCLUSIONS: Sperm DNA damage is associated with poor semen quality but not with seminal leukocyte subsets in infertile males with asymptomatic genital tract infection.


Subject(s)
Asymptomatic Infections , DNA Fragmentation , Deoxyguanosine/analogs & derivatives , Infertility, Male/genetics , Leukocytes/cytology , Sperm Count , Spermatozoa/pathology , 8-Hydroxy-2'-Deoxyguanosine , Adult , Age Factors , DNA Damage , Deoxyguanosine/analysis , Flow Cytometry , Humans , Infertility, Male/pathology , Leukocyte Common Antigens , Male , Oxidative Stress , Reproductive Tract Infections , Semen , Semen Analysis , Smoking , Spermatozoa/chemistry
15.
Nan Fang Yi Ke Da Xue Xue Bao ; 38(6): 704-710, 2018 Jun 20.
Article in Chinese | MEDLINE | ID: mdl-29997093

ABSTRACT

OBJECTIVE: To explore whether vimentin (VIM) mediates the activation of inflammasome in mice with EV71 infection in the central nervous system. METHODS: Forty VIM knockout mice (VIM-/-, 3 to 5 days old) were randomly divided into control group and infection group. The infection group was intraperitoneally injected with EV71 (108 TCID50), while the control group was injected with PBS (10 µL); another 40 wild-type mice (WT, 3 to 5 days old) were grouped in the same manner. The general conditions of mice were observed each day. Western blotting, ELISA, and RT-PCR were used to measure the levels of IL-1ß and casepase-1 in the brain or cerebrospinal fluid. The pathological changes in the cerebella and brain were observed using immunohistochemistry. RESULTS: Compared with the control group, the VIM-/- mice infected with EV71 showed no significant changes in NLRP3, IL-1ß or caspase-1 expression. The WT mice infected with EV71 showed obviously increased NLRP3, IL-1ß, and caspase-1 expressions in the central nervous system. The neurons of infected VIM-/- mice exhibited milder cell damage than the those in WT mice. CONCLUSION: VIM mediates the activation of inflammasome and promotes brain inflammation and neuronal damage in mice with EV71 infection in the central nervous system.


Subject(s)
Brain/drug effects , Central Nervous System Viral Diseases/metabolism , Enterovirus A, Human , Enterovirus Infections/metabolism , Inflammasomes/drug effects , NLR Family, Pyrin Domain-Containing 3 Protein/drug effects , Vimentin/pharmacology , Animals , Brain/metabolism , Brain/virology , Caspase 1/cerebrospinal fluid , Caspase 1/metabolism , Central Nervous System Viral Diseases/cerebrospinal fluid , Central Nervous System Viral Diseases/virology , Enterovirus Infections/cerebrospinal fluid , Enterovirus Infections/virology , Interleukin-1beta/cerebrospinal fluid , Interleukin-1beta/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , NLR Family, Pyrin Domain-Containing 3 Protein/cerebrospinal fluid , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Random Allocation , Vimentin/genetics
16.
Chemistry ; 24(23): 6277-6281, 2018 Apr 20.
Article in English | MEDLINE | ID: mdl-29498105

ABSTRACT

The dearomatizative dienamine-type ortho-quinodimethane species are smoothly generated between 2-alkyl-3-furfurals and chiral secondary amine catalysts, which undergo asymmetric benzylic allylic alkylation reactions with 2-nitroallylic acetates efficiently. A spectrum of densely functionalized 3-furfural derivatives are delivered in moderate to high yields with good to excellent diastereo- and enantioselectivity (up to 98 % yield, >19:1 d.r., >99 % ee). The latent transformations allow the facile production of some enantioenriched architectures, such as 1,1,2,2-tetraarylethanes and triarylmethanes, which are not easily available from other protocols.

17.
Org Lett ; 20(3): 804-807, 2018 02 02.
Article in English | MEDLINE | ID: mdl-29355329

ABSTRACT

A previously unreported activation mode is developed through the generation of dearomatizative tetraenamine species between 5-allylic furfurals and a bifunctional amine-thiourea catalyst. The very remote ζ,η-alkenes perform as effective HOMO-raised dienophiles in inverse-electron-demand oxa-Diels-Alder cycloadditions with isatin-derived oxadiene substrates, delivering multifunctional spirocyclic oxindoles incorporating a dihydropyran skeleton in moderate to high yields with good to excellent enantio- and diastereoselectivity.

18.
Carbohydr Polym ; 174: 572-579, 2017 Oct 15.
Article in English | MEDLINE | ID: mdl-28821107

ABSTRACT

Photophobic (white) films were prepared with hydroxypropyl methylcellulose (HPMC) and monosodium phosphate (NaH2PO4) to overcome the redox reaction induced by titanium dioxide photocatalysis of HPMC/TiO2 white film. What's more, HPMC/NaH2PO4 white film could overcome the drying temperature dependent property of white films based on HPMC and calcium salts. Attenuated total reflection Fourier transform infrared spectroscopy, wide angel X-ray diffraction, small angle X-ray scattering, scanning electron microscope and texture analyzer were used to investigate the effect of NaH2PO4 on the short-range, supra-molecular structures and properties of HPMC film. The formation mechanism of the white film was speculated by analyzing the structures of different scales. The results showed that the interaction might happen between H2PO4-1 group of NaH2PO4 and CH, CH2 and CH3 group of HPMC. These interactions influenced the polymer chain movement and combination and further affected the aggregation structures. Specifically, the compactness, smoothness and scale range of the surface fractal scatters in films increased and elongated particles of two scales appeared. These changes of ordered structure in the micro-region might contribute to increasing the reflected light and decreasing the transmission light of films, resulting in white films with photophobic property. The addition of NaH2PO4 decreased the crystallinity and smoothness of the cross-section of HPMC film, which resulted in a little lower tensile strength, elongation and elastic modulus of HPMC/NaH2PO4 films. Films of less than 10% of NaH2PO4 showed similar mechanical properties with pure HPMC film, which offered proper parameters for the production of HPMC/NaH2PO4 photophobic films in the application.

19.
Steroids ; 125: 54-60, 2017 09.
Article in English | MEDLINE | ID: mdl-28648585

ABSTRACT

In this paper, a new and concise synthetic route of lithocholic acid (LCA) using commercially available steroid source deoxycholic acid is reported. A series of amide derivatives of LCA were also synthesized and investigated for their activity against the growth of MCF-7 and MCF-7/ADR cells using the sulforhodamine B assay. For MCF-7, the most potent compound 20 showed a 20-fold higher antitumor activity than LCA. For MCF-7/ADR, the most potent compound 24 showed a 22-fold higher antitumor activity than LCA. The transwell migration assay of 20 was evaluated on MDA-MB-231 cells. The colony formation and apoptosis assays of 20 were performed on MCF-7 and MCF-7/ADR cell lines.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Lithocholic Acid/chemical synthesis , Lithocholic Acid/pharmacology , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Cell Movement/drug effects , Cell Proliferation/drug effects , Chemistry Techniques, Synthetic , Drug Screening Assays, Antitumor , Humans , Lithocholic Acid/chemistry , MCF-7 Cells , Structure-Activity Relationship
20.
Mol Cell ; 66(1): 154-162.e10, 2017 Apr 06.
Article in English | MEDLINE | ID: mdl-28344083

ABSTRACT

Hedgehog (Hh) has been known as the only cholesterol-modified morphogen playing pivotal roles in development and tumorigenesis. A major unsolved question is how Hh signaling regulates the activity of Smoothened (SMO). Here, we performed an unbiased biochemical screen and identified that SMO was covalently modified by cholesterol on the Asp95 (D95) residue through an ester bond. This modification was inhibited by Patched-1 (Ptch1) but enhanced by Hh. The SMO(D95N) mutation, which could not be cholesterol modified, was refractory to Hh-stimulated ciliary localization and failed to activate downstream signaling. Furthermore, homozygous SmoD99N/D99N (the equivalent residue in mouse) knockin mice were embryonic lethal with severe cardiac defects, phenocopying the Smo-/- mice. Together, the results of our study suggest that Hh signaling transduces to SMO through modulating its cholesterylation and provides a therapeutic opportunity to treat Hh-pathway-related cancers by targeting SMO cholesterylation.


Subject(s)
Cholesterol/metabolism , Hedgehog Proteins/metabolism , Signal Transduction , Smoothened Receptor/metabolism , Animals , CHO Cells , Cilia/metabolism , Cricetulus , Gene Expression Regulation, Developmental , Genetic Predisposition to Disease , HEK293 Cells , Heart Defects, Congenital/genetics , Heart Defects, Congenital/metabolism , Hedgehog Proteins/genetics , Humans , Mice , Mice, Transgenic , Mutation , NIH 3T3 Cells , Patched-1 Receptor/genetics , Patched-1 Receptor/metabolism , Phenotype , Protein Processing, Post-Translational , RNA Interference , Smoothened Receptor/genetics , Transfection
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