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1.
J Org Chem ; 86(21): 14915-14927, 2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34570982

RESUMEN

We have developed cobalt-catalyzed, bidentate 2-(1-methylhydrazinyl)pyridine (MHP)-directed C(sp2)-H alkylation/annulation of benzoic hydrazides with various alkenes. Notably, diverse cyclopenta[c]isoquinolinones and dihydroisoquinolinones were obtained via this functional group-tolerant protocol. The reaction can be performed on a gram scale while maintaining an excellent yield, and the directing group can be removed efficiently under mild conditions. Furthermore, density-functional theory (DFT) calculations provide an incisive understanding of the observed regioselectivities for different olefins.


Asunto(s)
Cobalto , Piridinas , Alquenos , Alquilación , Catálisis
2.
Org Biomol Chem ; 15(30): 6349-6352, 2017 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-28703245

RESUMEN

A blue-light-promoted carbon-carbon double bond isomerization in the absence of any photoredox catalyst is reported. It provides rapid access to a series of quinolines in good to excellent yields under simple aerobic conditions. The protocol is direct, catalyst-free and operationally convenient.

3.
J Org Chem ; 80(24): 12725-32, 2015 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-26595127

RESUMEN

A novel copper-catalyzed regioselective double carbonylation of imidazo[1,2-a]pyridines with N,N-disubstituted acetamide or acetone using molecular oxygen has been described. It has provided a new approach to synthesize 1,2-carbonyl imidazo[1,2-a]pyridines, which are important substrates and intermediates in preparation of fine chemicals. The product shares a skeleton similar to that of Zolpidem, one of the most prescribed drugs in the world. (18)O-labeling experiments unambiguously established that the oxygen source of products originated from O2 rather than H2O.

4.
Chempluschem ; 86(9): 1322-1341, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34363342

RESUMEN

Owing to the low price, chemical stability and good conductivity, carbon-based materials have been extensively applied as the anode in microbial fuel cells (MFCs). In this review, apart from the charge storage mechanism and anode requirements, the major work focuses on five categories of carbon-based anode materials (traditional carbon, porous carbon, nano-carbon, metal/carbon composite and polymer/carbon composite). The relationship is demonstrated in depth between the physicochemical properties of the anode surface/interface/bulk (porosity, surface area, hydrophilicity, partical size, charge, roughness, etc.) and the bioelectrochemical performances (electron transfer, electrolyte diffusion, capacitance, toxicity, start-up time, current, power density, voltage, etc.). An outlook for future work is also proposed.

5.
ACS Omega ; 6(39): 25151-25161, 2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34632174

RESUMEN

Palladium-catalyzed C(sp2)-H arylation of ortho C-H bonds involving 2-(1-methylhydrazinyl)pyridine (MHP) as the directing group has been investigated. The reaction proceeds smoothly under an air atmosphere to generate biaryl derivatives in an environmentally friendly manner while tolerating a wide range of functional groups. Notably, the directing group present in the product could be easily removed under mild reductive conditions.

6.
Transl Lung Cancer Res ; 10(3): 1408-1423, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33889519

RESUMEN

BACKGROUND: Metastatic non-small cell lung cancer (NSCLC) has many comorbidities, such as chronic obstructive pulmonary disease, coronary heart disease, and older age-related comorbidities. A survival benefit was observed in such patients who underwent surgery for selected oligometastatic disease. However, to the best of our knowledge, there is no evidence to support whether lobectomy (compared with sub-lobar resection) would further prolong these patients' lives. METHODS: Patients with metastatic NSCLC who underwent primary tumor resection were identified from the Surveillance, Epidemiology, and End Results (SEER) database and then divided into lobectomy and sub-lobar resection groups. Propensity score matching (PSM, 1:1) was performed to match the baseline characteristics of the two groups. Cancer-specific survival (CSS) was estimated. RESULTS: In total, 24,268 patients with metastatic NSCLC were identified; 4,114 (16.95%) underwent primary tumor surgery, and of these, 2,045 (49.71%) underwent lobectomy and 1,766 (42.93%) underwent sub-lobar resection. After PSM, 644 patients in each group were included. Lobectomy was independently correlated with longer median CSS time [hazards ratio (HR): 0.70, 95% confidence interval (CI): 0.61-0.80, P<0.001]. The 1, 2, and 3-year survival rates after PSM also favored the lobectomy group. However, no significant survival difference was found for wedge resection and segmentectomy (HR: 0.96, 95% CI: 0.70-1.31, P=0.490). The 1-, 2-, and 3-year survival rates after PSM also exhibited no difference within the sub-lobar group. We explored whether lymph node dissection would provide additional survival benefits for stage IV NSCLC patients. According to the multivariate Cox analysis of the matched population, lymph node dissection was independently associated with better CSS (HR: 0.76, 95% CI: 0.66-0.88, P<0.001) and overall survival (OS) (HR: 0.74, 95% CI: 0.65-0.86, P<0.001). We confirmed this result in the different types of surgery and found that the lymph node dissection group consistently had better survival outcomes both in the lobectomy group and sub-lobar resection population. According to the subgroup analysis, with the exception of stage T4 and brain metastatic patients, all of the patient subtypes exhibited greater benefit from lobectomy than sub-lobar resection. CONCLUSIONS: Lobectomy has a greater survival benefit in metastatic NSCLC patients compared with sub-lobar resection when radical treatment of primary site was indicated.

7.
Chem Commun (Camb) ; 56(23): 3405-3408, 2020 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-32091059

RESUMEN

We have developed a unique approach for the thermally promoted cycloaddition of cyclohexadienone-tethered allenes to form a versatile cyclobutane-fused oxygen-containing tricyclic framework in an environmentally friendly and atomic economic fashion with high regioselectivity. The reaction encompasses a broad substrate scope and functional group tolerance of cyclohexadienone moieties. Moreover, the cycloaddition was also applicable to the late-stage functionalization of pharmaceutically relevant compounds.

8.
Chem Commun (Camb) ; 55(29): 4206-4209, 2019 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-30895992

RESUMEN

We have developed a one-pot synthesis of benzo[b]fluorenones via a cobalt-catalyzed [3+2] annulation of oxabicyclic alkenes followed by a ring-opening/dehydration sequence in good to excellent yields. With the use of 2-(1-methylhydrazinyl)pyridine (MHP), first explored by our group as the bidentate directing group in C-H functionalization of benzoic hydrazides, the new reaction sequence proceeded smoothly and tolerated a wide range of functional groups, featuring facile scalability. Notably, oxygen served as the green oxidant in the reaction system. Careful tuning of the reaction parameters assured the direct synthesis of benzo[b]fluorenones through aromatization of the dihydroepoxybenzofluorenone intermediate.

9.
Ann Transl Med ; 7(12): 257, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31355224

RESUMEN

BACKGROUND: For subjects with out-of-hospital cardiac arrest (OHCA), bag-valve mask (BVM), endotracheal intubation (ETI), and laryngeal mask airway (LMA) are the most common methods of ventilatory support; however, the best choice remains controversial. METHODS: A comprehensive search of online databases was performed. A traditional meta-analysis was performed to determine the risk ratio of BVM vs. LMA and ETI vs. LMA. Indirect treatment comparisons (ITCs) were conducted to compare BVM and ETI. RESULTS: A total of 13 full-text articles reporting the efficacy of BVM, ETI, and LMA were considered in this analysis. BVM and LMA had the same effect regarding return of spontaneous circulation (ROSC) (23% vs. 24%; RR =0.84), survival rate at admission (19% vs. 21%; RR =0.82) or discharge (6% vs. 4%; RR =0.61). ETI was superior to LMA in terms of ROSC (48% vs. 23%; RR =0.72) and survival rate at both admission (27% vs. 19%; RR =0.85) and discharge (12% vs. 4%; RR =0.90). BVM was inferior to ETI in terms of ROSC (24% vs. 48%; RR =0.86), survival to admission rate (21% vs. 27%; RR =1.037), and survival to discharge rate (6% vs. 12%; RR =1.476). CONCLUSIONS: ETI should be considered for airway management as early as possible, which can improve the subject's success rate of recovery and survival to admission rate. In future, large-scale, multi-center, randomized controlled studies should be conducted to evaluate the exact efficacy of BVM, ETI, and LMA for the first aid of subjects with OHCA.

10.
Chem Commun (Camb) ; 54(39): 4927-4930, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29693085

RESUMEN

A cobalt-catalyzed oxidative coupling of benzoic hydrazides with maleimides by utilizing 2-(1-methylhydrazinyl)pyridine as a bidentate directing group has been developed. This C-H functionalization/spirocyclization cascade protocol shows high efficiency and remarkable functional group tolerance, and the ubiquitous spirosuccinimides were obtained in good to excellent yields with high regioselectivity. This strategy also provides a novel and efficient access to diverse symmetric and unsymmetrical bisspirosuccinimides.

11.
Chem Commun (Camb) ; 54(1): 98-101, 2017 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-29211070

RESUMEN

We describe a new application of 2-(1-methylhydrazinyl)pyridine as a bidentate directing group to directing cobalt-catalyzed C(sp2)-H alkenylation/annulation of the corresponding benzoic hydrazides to form an isoquinoline backbone, via reacting with a terminal or internal alkyne followed by annulation. The reaction shows a broad substrate scope with the products obtained in good to excellent yields and high regioselectivity. Moreover, the directing group can be reductively removed in one step under mild conditions.

12.
Chem Commun (Camb) ; 51(10): 1823-5, 2015 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-25519843

RESUMEN

Using the widely available DMSO as the formylation reagent under oxidative conditions, an efficient Cu-catalyzed C3-formylation reaction of imidazo[1,2-a]pyridine C-H bonds to directly generate structurally sophisticated 3-formyl imidazo[1,2-a]pyridine derivatives has been developed. The reaction proceeded to generate products in good yields, and used the environmentally friendly molecular oxygen as the oxidant.


Asunto(s)
Cobre/química , Dimetilsulfóxido/química , Imidazoles/química , Oxígeno/química , Piridinas/síntesis química , Catálisis , Enlace de Hidrógeno , Oxidación-Reducción , Piridinas/química
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