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1.
Org Lett ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32056438

RESUMO

A new methodology for the carbonylative transformation of N-fluoro-sulfonamides into N-sulfonyl-ß-homoproline esters has been described. In the presence of a catalytic amount of Cu(OTf)2, a range of ß-homoproline derivatives were prepared in moderate to good yield. The reaction proceeds via the intramolecular cyclization and intermolecular carbonylation of a free carbon radical. Notably, this procedure offers the possibility to build potential functionalized bioactive molecules.

2.
Chem Asian J ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32057186

RESUMO

In this communication, we have developed a facile and efficient procedure for the synthesis of diarylphosphate esters and amides. Using Zn(acac) 2 as the catalyst, the reaction of diarylphosphoryl azides with aliphatic alcohols and phe-nols through an unusual P-N bond cleavage provided a number of diarylphosphate esters in good yields (22 examples, up to 94%). Additionally, various diarylphosphate amides were achieved from the corresponding amines in excellent yields as well (8 examples, up to 96%).

3.
Artigo em Inglês | MEDLINE | ID: mdl-32067173

RESUMO

Three-dimensional cubic ordered mesoporous carbon with chitosan (Ia3d-CS), which was synthesized via exothermic reaction between liquid potassium and carbon monoxide gas, was coated on the active carbon (AC) electrode as a capacitive deionization (CDI) disinfection electrode. The results showed that Ia3d-CS-2 as CDI electrode exhibited the quick ion diffusion and strong charge transfer performance, due to the three-dimensional pore structure and specific surface area. The electrode of Ia3d-CS-2 displayed a specific capacity of 191.22 F/g at a scan rate of 100 mV·s-1 in 0.5 M NaCl aqueous solution. In a CDI recycling system, Ia3d-CS-x electrode showed good cyclic stability, and the electrosorption capacity of Ia3d-CS-2 electrode can achieve 1.31 mg/g at 1.2 V in 100 mg/l NaCl aqueous solutions. Subsequently, Ia3d-CS-2 electrode had an excellent disinfection efficiency of killing about 99.99% Escherichia coli within 30 min during the CDI process at applied 1.2 V. Considering those excellent properties of the fabricated Ia3d-CS-x electrode, which should be a better candidate for high-performance deionization application.

4.
Future Oncol ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32067473

RESUMO

Colorectal cancer is the third most common cancer in the world and its incidence is on the rise. Dietary intervention has emerged as an attractive strategy to curtail its occurrence and progression. Diet is known to influence the gut microbiome, as dietary factors and gut bacteria can act in concert to cause or protect from colorectal cancer. Several studies have presented evidence for such interactions and have pointed out the different ways by which the diet and gut microbiome can be altered to produce beneficial effects. This review article aims to summarize the interrelationship between diet, gut flora and colorectal cancer so that a better preventive approach can be applied.

5.
J Gen Virol ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32003710

RESUMO

Our previous study showed that the Bombyx mori nucleopolyhedrovirus (BmNPV) F-like protein Bm14 is intrinsically related to the production of occlusion bodies, occlusion-derived virus (ODV) embedding and virulence in infected larvae. However, the exact mechanism by which Bm14 affects primary infection remains unknown. In this report, we characterized the detailed distribution and topology of Bm14 in occlusion bodies (OBs) and ODVs, and then further investigated the functional role of Bm14 in primary infection. A combination of Western blot and immunoelectron microscopy showed that Bm14 is mainly present on the surface of ODVs within OBs, but rarely in the OB matrix. Further phase separation and topology analysis of Bm14 by selective permeabilization revealed that Bm14 is a type I integral membrane protein with an N-terminus hidden in the endoplasmic reticulum (ER) lumen and a C-terminus exposed to the cytosol. In vivo assays demonstrated that the disruption of bm14 impaired the interactions of ODV with midgut epithelia, resulting in delayed spread in larval tissues. As the essential trigger of primary infection, some per os infectivity factors (PIFs) were verified to interact with Bm14 via a series of coimmunoprecipitation analyses. Further partially denaturing SDS-PAGE and BN-PAGE assays clearly showed that the deletion of bm14 did not affect the formation and presence of the PIF complex. In conclusion, Bm14 functions as a type I integral membrane protein to regulate ODV attachment to the midgut epithelial cells.

6.
Org Lett ; 22(2): 636-641, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31908172

RESUMO

In this work, an interesting and practical procedure for the synthesis of 1,2-diketones from aryl halides and organoaluminum reagents has been developed. Employing tert-butyl isocyanide as the CO source and palladium as the catalyst, the desired 1,2-diketones were isolated in good to excellent yields with good functional group tolerance. Concerning the reaction partners, besides aryl halides, both alkyl- and arylaluminum reagents were all suitable substrates here.

7.
Theor Appl Genet ; 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31989206

RESUMO

KEY MESSAGE: The qHTB1-1 QTL, controlling heat tolerance at the booting stage in rice, was fine mapped to a 47.1 kb region containing eight candidate genes. Two positional candidate genes showed significant changes in expression levels under heat stress. High-temperature stress at the booting stage has the potential to significantly limit rice production. An interspecific advanced backcrossed population between the Oryza sativa L. cultivar R53 and the wild Oryza rufipogon Griff accession HHT4 was used as the source material to develop a set of chromosome segment introgression lines to elucidate the genetic mechanism of the qHTB1-1 QTL in heat tolerance. A single-chromosome-segment introgression line, IL01-15, was used to develop secondary populations for the mapping of qHTB1-1 on chromosome 1 for heat tolerance at the booting stage. Using the BC5F2, BC5F3, and BC5F4 populations, we first confirmed qHTB1-1 and validated the phenotypic effect. The qHTB1-1 QTL explained 13.1%, 16.9%, and 17.8% of the phenotypic variance observed in the BC5F2, BC5F3, and BC5F4 generations, respectively. Using homozygous recombinants screened from larger BC6F2 and BC6F3 populations, qHTB1-1 was fine mapped within a 47.1 kb region between markers RM11633 and RM11642. Eight putative predicted genes were annotated in the region, and six genes were predicted to encode expressed proteins. The expression patterns of these six genes demonstrated that LOC_Os01g53160 and LOC_Os01g53220 were highly induced by heat stress in IL01-15 compared to R53. Sequence comparison of the gene-coding regions of LOC_Os01g53160 and LOC_Os01g53220 between R53 and IL01-15 revealed one synonymous and two nonsynonymous SNPs in exons, respectively. Our results provide a basis for identifying the genes underlying qHTB1-1 and indicate that markers linked to the qHTB1-1 locus can be used to improve the heat tolerance of rice at the booting stage by marker-assisted selection.

8.
Org Lett ; 22(3): 1160-1163, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31965807

RESUMO

In this communication, an interesting carbonylation protocol for the preparation of α-branched enones has been established. Starting from readily available aryl iodides and allenes, with formic acid as the CO source and reductant, moderate to good yields of the desired enones were isolated. Although it is a carbonylation methodology, the use of a CO source can avoid the manipulation of CO gas directly. Notably, this procedure also presents the first example on carbonylative synthesis of α-branched enones.

9.
J Viral Hepat ; 27(1): 45-51, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31520460

RESUMO

A simple, pangenotypic and effective treatment regimen for patients with a broad range of chronic hepatitis C virus (HCV) infections remains an unmet medical need. We conducted a phase 2, randomized, open study involving untreated patients with chronic HCV genotypes 1, 2, 3, or 6 infections. Patients without cirrhosis were randomly assigned in a 1:2 ratio to receive capsules of the NS5A inhibitor coblopasvir at a dose of 30 or 60 mg plus tablets of the nucleotide polymerase inhibitor sofosbuvir (400 mg) once daily for 12 weeks. Patients with cirrhosis received 60 mg coblopasvir plus sofosbuvir for 12 weeks. The primary endpoint was the sustained virologic response at 12 weeks after the end of therapy (SVR12). Of the 110 patients who were enrolled in the study, 59 were male, 62.7% had HCV genotype 1, 24.5% had genotype 2, 6.4% had genotype 3, and 6.4% had genotype 6. The average age was 45.5 years. A total of 10.9% of patients had compensated cirrhosis. The rate of SVR12 was 98.2% in the intention-to-treat (ITT). One genotype 6 patient with cirrhosis experienced virologic relapse. One genotype 2 patient without cirrhosis failed to complete the follow-up and quit the study. Serious adverse events (SAEs) were reported in 2 patients and were not related to coblopasvir and sofosbuvir. Most adverse events (AEs) did not require treatment. Coblopasvir plus sofosbuvir taken once daily for 12 weeks provided high rates of sustained virologic response (SVR) and had a good safety profile among patients with HCV genotypes 1, 2, 3, or 6 infections, including those with compensated cirrhosis.

10.
Eur J Med Chem ; 187: 111959, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31846830

RESUMO

Chlorophyll a exhibits excellent photosensitive activity in photosynthesis. The unstability limited its application as photoensitizer drug in photodynamic therapy. Here a series of novel chlorophyll a degradation products pyropheophorbide-a derivatives were synthesized and evaluated for lung cancer in PDT. These compounds have strong absorption in 660-670 nm with high molar extinction coefficient, and fluorescence emission in 660-675 nm upon excitation with 410-415 nm light. They all have much higher ROS yields than pyropheophorbide-a, and compound 10 was even higher than [3-(1-hexyloxyethyl)]-pyrophoeophorbide a (HPPH). Distinctive phototoxicity was observed in vitro and the inhibition effect was in light dose-dependent and drug dose-dependent style. They can effectively inhibit the growth of lung tumor in vivo. Among them, compound 8 and 11 have outstanding photodynamic anti-tumor effects without obvious skin photo-toxicity, so they can act as new drug candidates for photodynamic therapy.

11.
Virology ; 539: 61-68, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31678757

RESUMO

Our previous study showed that Bombyx mori nucleopolyhedrovirus F-like protein Bm14 is involved in infectious BV production and its deletion reduces the production rate. However, the peculiar relationship between Bm14 and GP64, two major BV envelope proteins, is still unknown. Here, we demonstrated the predominant distribution of Bm14 in BVs rather than in ODVs. Further experiments revealed that the absence of Bm14 moderately reduced trafficking of GP64 to the plasma membrane and impaired GP64-mediated fusion activity. Coimmunoprecipitation analysis demonstrated the associations of Bm14 with GP64, and confocal microscopy also displayed their colocalization throughout nonviral or viral infection. More interestingly, an approximately 270-kDa complex containing Bm14 and GP64 was detected in the cytoplasm using BN-PAGE and Western blotting. The disruption of Bm14 resulted in a subcomplex of ~190 kDa. Collectively, Bm14 functions as a cofactor of GP64 via forming a complex on the surface of BVs, thus affecting the efficient infection.

12.
Angew Chem Int Ed Engl ; 59(5): 1770-1774, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31886570

RESUMO

Organoboron compounds are among the most versatile and useful building blocks in modern synthetic chemistry. The past decades have seen impressive developments in the direct C-H bond borylation of (hetero)arenes in which the applied catalysts are shifting from noble metals to metal-free systems. This Highlight gives a brief summary on this evolution and focuses on recent elegant work in this field.

13.
Org Lett ; 22(1): 194-198, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31858806

RESUMO

In this letter, we developed a palladium-catalyzed procedure for the cyclocarbonylation of propargyl amines. Benzene-1,3,5-triyl triformate (TFBen) has been explored as the CO source and also as the key promotor. Various substituted 2-oxo-dihydropyrroles were produced in a facile manner in good yields (up to 90%).

14.
Int J Mol Sci ; 20(22)2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31703454

RESUMO

Current therapies are insufficient for metastatic prostate cancer (PCa) in men and dogs. As human castrate-resistant PCa shares several characteristics with the canine disease, comparative evaluation of novel therapeutic agents is of considerable value for both species. Novel isoquinolinamine FX-9 exhibits antiproliferative activity in acute lymphoblastic leukemia cell lines but has not been tested yet on any solid neoplasia type. In this study, FX-9's mediated effects were characterized on two human (PC-3, LNCaP) and two canine (CT1258, 0846) PCa cell lines, as well as benign solid tissue cells. FX-9 significantly inhibited cell viability and induced apoptosis with concentrations in the low micromolar range. Mediated effects were highly comparable between the PCa cell lines of both species, but less pronounced on non-malignant chondrocytes and fibroblasts. Interestingly, FX-9 exposure also leads to the formation and survival of enlarged multinucleated cells through mitotic slippage. Based on the results, FX-9 acts as an anti-mitotic agent with reduced cytotoxic activity in benign cells. The characterization of FX-9-induced effects on PCa cells provides a basis for in vivo studies with the potential of valuable transferable findings to the benefit of men and dogs.

15.
J Org Chem ; 84(21): 14297-14305, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31589044

RESUMO

A palladium-catalyzed site-selective C-H carbonylation of heterocyclic amines for the synthesis of lactam motifs has been developed. The reaction of 3-thiophene methylamines, 2-thiophene methylamines, and tryptamines with benzene-1,3,5-triyl triformate (TFBen) as the CO source provides a series of structurally diverse lactams in moderate to high yields with excellent regioselectivities.

16.
Org Lett ; 21(20): 8215-8218, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31565941

RESUMO

In this Letter, a palladium-catalyzed multicomponent procedure for the selective synthesis of α-substituted α,ß-unsaturated ketones has been developed. With readily available allenes, arylboronic acids, and nitroarenes as the substrates, the reaction proceeds selectively to the desired α-substituted enones. Notably, no manipulation of carbon monoxide gas is needed here, and Mo(CO)6 has been applied as a stable solid CO source instead. Additionally, as an oxidative coupling reaction, nitroarenes are used as both the amine source and the oxidant to regenerate the active palladium species.

18.
J Org Chem ; 84(19): 12648-12655, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31495167

RESUMO

A cobalt-catalyzed direct carbonylative synthesis of phthalimide motifs from N-(pyridin-2-ylmethyl)benzamides has been developed. Various phthalimide derivatives were obtained in moderate to excellent yields (up to 98%) by using 2-picolylamine as an efficient directing group and benzene-1,3,5-triyl triformate (TFBen) as a convenient CO surrogate.

19.
Materials (Basel) ; 12(17)2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31480773

RESUMO

Cold spray additive manufacturing is an emerging technology that offers the ability to deposit oxygen-sensitive materials and to manufacture large components in the solid state. For further development of the technology, the geometric control of cold sprayed components is fundamental but not yet fully matured. This study presents a neural network predictive modelling of a single-track profile in cold spray additive manufacturing to address the problem. In contrast to previous studies focusing only on key geometric feature predictions, the neural network model was employed to demonstrate its capability of predicting complete track profiles at both normal and off-normal spray angles, resulting in a mean absolute error of 8.3%. We also compared the track profile modelling results against the previously proposed Gaussian model and showed that the neural network model provided comparable predictive accuracy, even outperforming in the predictions at cold spray profile edges. The results indicate that a neural network modelling approach is well suited to cold spray profile prediction and may be used to improve geometric control during additive manufacturing with an appropriate process planning algorithm.

20.
Org Lett ; 21(18): 7624-7629, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31483670

RESUMO

A highly reactive catalytic system for the carbonylative coupling of aryl iodides with alkenylaluminum reagents has been developed. Various ß-substituted γ,δ-unsaturated ketones were produced under mild conditions in good to excellent yields even under ppm level of palladium catalyst. Notably, this also represents the first example on carbonylative transformation of alkenylaluminum compounds. Additionally, by the addition of zinc salt, the selectivity of the product can be modified.

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