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1.
J Asian Nat Prod Res ; 25(10): 999-1011, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36899456

RESUMEN

Osthole is the prominent active ingredient isolated from Cnidium. The role of osthole in chronic obstructive pulmonary disease (COPD) was investigated herein. Bronchial epithelial 16HBE cells were exposed to cigarette smoke extract (CSE) to generate injury models. The concentration of CSE had an inverse correlation with cell viability. Osthole suppressed inflammation, oxidative stress, apoptosis, and pyroptosis in 16HBE cells, along with a decrease in RIPK2 level. RIPK2 overexpression reversed the effects of osthole on the abovementioned aspects. This study found that the osthole could reduce RIPK2 level, inhibit pyroptosis, and alleviate the damage in 16HBE cells under CSE stimulation.


Asunto(s)
Cnidium , Piroptosis , Línea Celular , Apoptosis , Nicotiana , Células Epiteliales
2.
Chemistry ; 20(47): 15334-8, 2014 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-25308802

RESUMEN

A copper-catalyzed reductive cross-coupling reaction of nonactivated alkyl tosylates and mesylates with alkyl and aryl bromides was developed. It provides a practical method for efficient and cost-effective construction of aryl-alkyl and alkyl-alkyl CC bonds with stereocontrol from readily available substrates. When used in an intramolecular fashion, the reaction enables convenient access to various substituted carbo- or heterocycles, such as 2,3-dihydrobenzofuran and benzochromene derivatives.

3.
Chemistry ; 20(47): 15339-43, 2014 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-25314635

RESUMEN

A novel method for the synthesis of non-natural L- and D-amino acids by a Ni-catalyzed reductive cross-coupling reaction is described. This strategy enables the racemization-free cross-coupling of serine/homoserine- derived iodides with aryl/acyl/alkyl halides. It provides convenient access to varieties of enantiopure and functionalized amino acids, which are important building blocks in bioactive compounds and pharmaceuticals.


Asunto(s)
Aminoácidos/química , Níquel/química , Aminoácidos/síntesis química , Catálisis , Cristalografía por Rayos X , Halógenos/química , Conformación Molecular , Acoplamiento Oxidativo , Estereoisomerismo
4.
Clin Breast Cancer ; 24(3): e167-e176, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38212189

RESUMEN

BACKGROUND: There are significant correlations between the levels of tumor infiltrating lymphocytes (TILs) and the prognosis of primary breast cancer. While little is known about immunological mechanisms in the distant metastasis of advanced breast cancer. PATIENTS AND METHODS: A total of 106 patients with advanced metastatic breast cancer were enrolled in this study between 2016 and 2022. Hematoxylin and eosin staining and immunohistochemistry were used to assess the densities of stromal TILs (sTILs), intratumoral TILs (iTILs) and invasive marginal TILs (imTILs) and CD4+, CD8+, CD20+, FOXP3+ TILs in the primary tumor and metastasis (bone, lung, liver, and distant lymph node) of advanced breast cancer. RESULTS: Higher levels of sTILs at metastatic sites were associated with better progression-free survival (PFS), postmetastasis survival (PMS) and overall survival (OS) (p = .026, .001 and .005, respectively). The levels of iTILs were significantly lower than those of sTILs and imTILs in both primary tumor (p< .001, both) and metastasis (p< .001, both). The level of CD4+ T cells was higher than those of CD8+ T cells and CD20+ B cells in both primary tumor (p < .001) and metastasis (p < .001). The levels of sTILs (p=0. 001) and imTILs (p< .001) in the primary tumor were generally higher than those in the metastasis. CONCLUSION: The levels of TILs and their subsets can predict the survival and prognosis of patients with advanced breast cancer. The distributions of TILs and their subsets are similar between the primary tumor and metastasis. The metastases have a lower degree of lymphocytes infiltration than its corresponding primary tumor.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Pronóstico , Linfocitos Infiltrantes de Tumor , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos
5.
J Am Chem Soc ; 134(27): 11124-7, 2012 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-22734716

RESUMEN

Practical catalytic cross-coupling of secondary alkyl electrophiles with secondary alkyl nucleophiles under Cu catalysis has been realized. The use of TMEDA and LiOMe is critical for the success of the reaction. This cross-coupling reaction occurs via an S(N)2 mechanism with inversion of configuration and therefore provides a general approach for the stereocontrolled formation of C-C bonds between two tertiary carbons from chiral secondary alcohols.

6.
Angew Chem Int Ed Engl ; 51(2): 528-32, 2012 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-22135233

RESUMEN

Easy access: An unprecedented copper-catalyzed cross-coupling reaction of the title compounds with diboron reagents is described (see scheme; Ts = 4-toluenesulfonyl). This reaction can be used to prepare both primary and secondary alkylboronic esters having diverse structures and functional groups. The resulting products would be difficult to access by other means.


Asunto(s)
Compuestos de Boro/síntesis química , Cobre/química , Alquilación , Compuestos de Boro/química , Catálisis , Ésteres/síntesis química , Ésteres/química
7.
Chem Commun (Camb) ; 53(25): 3551-3554, 2017 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-28286887

RESUMEN

A Cu/PPh3-catalyzed propargylic substitution reaction of diborylmethane is reported. Different substituted propargyl electrophiles can be employed in this reaction, and various synthetic valuable functional groups can be tolerated. Di-deuterated diborylmethane can also be used under these conditions and generates α-deuterated alkylboronic esters in good yield.

8.
Chem Commun (Camb) ; 53(5): 909-912, 2017 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-28008446

RESUMEN

We report the first copper-catalyzed/mediated borylative ring opening reaction of epoxides. This process represents a direct borylative C(sp3)-O bond cleavage of terminal epoxide substrates with commercially available diboron reagents. A wide range of epoxides with different functional groups are involved, and were subsequently converted to the corresponding ß-hydroxyl boronic esters smoothly. Moreover, the ring opening product ß-pinacol boronate alcohol provided a more beneficial approach for the formation of C-C and C-N bonds.

10.
Chem Commun (Camb) ; 52(6): 1242-5, 2016 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-26611730

RESUMEN

A copper-mediated directed demethylation of propionamides has been developed. This reaction proceeds predominantly at the α-methyl groups of aliphatic amides with high efficiency and provides a unique tool for the direct cleavage of unactivated C(sp(3))-C(sp(3)) bonds. The directing groups can be smoothly removed to afford the corresponding alkyl carboxylic acids.

11.
Org Lett ; 18(5): 952-5, 2016 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-26872072

RESUMEN

A Cu/(NHC)-catalyzed SN2'-selective substitution reaction of allylic electrophiles with gem-diborylalkanes is reported. Different substituted gem-diborylalkanes and allylic electrophiles can be employed in this reaction, and various synthetic valuable functional groups can be tolerated. The asymmetric version of this reaction was initially researched with chiral N-heterocyclic carbene (NHC) ligands.

12.
Chem Commun (Camb) ; 52(27): 4891-3, 2016 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-26973991

RESUMEN

Herein, we describe a novel copper-catalyzed epoxide opening reaction with gem-diborylmethane. Aliphatic, aromatic epoxides as well as aziridines are converted to the corresponding γ-pinacolboronate alcohols or amines in moderate to excellent yields. This new reaction provides beneficial applications for classic epoxide substrates as well as interesting gem-diborylalkane reagents.


Asunto(s)
Compuestos de Boro/química , Cobre/química , Compuestos Epoxi/química , Metano/química , Ésteres
13.
Chem Commun (Camb) ; 50(75): 11060-2, 2014 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-25102380

RESUMEN

A copper-catalyzed Suzuki-Miyaura coupling of benzyl halides with arylboronates is described. Varieties of primary benzyl halides as well as more challenging secondary benzyl halides with ß hydrogens or steric hindrance could be successfully converted into the corresponding products. Thus it provides access to diarylmethanes, diarylethanes and triarylmethanes.


Asunto(s)
Ácidos Borónicos/química , Cobre/química , Halógenos/química , Compuestos de Bencilo/química , Catálisis , Hidrógeno/química
14.
Org Lett ; 16(24): 6342-5, 2014 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-25436511

RESUMEN

The first copper-catalyzed/promoted sp(3)-C Suzuki-Miyaura coupling reaction of gem-diborylalkanes with nonactivated electrophilic reagents is reported. Not only 1, 1-diborylalkanes but also some other gem-diborylalkanes can be coupled with nonactivated primary alkyl halides, offering a new method for sp(3)C-sp(3)C bond formation and, simultaneously, providing a new strategy for the synthesis of alkylboronic esters.


Asunto(s)
Compuestos de Boro/química , Cobre/química , Reactivos de Enlaces Cruzados/química , Hidrocarburos Halogenados/química , Catálisis , Ésteres , Estructura Molecular
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