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1.
J Org Chem ; 86(21): 15153-15163, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34592103

RESUMEN

A direct B(4)-H monoacyloxylation via a Pd-catalyzed regioselective B(4)-H activation of o-carborane acids with phenyliodonium dicarboxylates was developed, and a series of B(4)-H monoacyloxylated o-carboranes decorated with active groups were synthesized with moderate to good yields as well as excellent selectivity. In addition, a direct B(4,5)-H diacetoxylation from o-carborane acids with phenyliodonium diacetate was demonstrated.

2.
Support Care Cancer ; 28(6): 2713-2719, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31691034

RESUMEN

PURPOSE: Many assert the need for home hospice care. However, limited research has shown its effectiveness. The authors of this study thus evaluated the effectiveness of a home hospice care pilot project regarding (1) early enrollment in hospice care, (2) efficient use of inpatient hospice resources, and (3) enabling terminally ill patients to stay at their preferred place of care. METHODS: The authors conducted a nationwide prospective observational study. Patients were divided into home hospice care users (ever-users, n = 902) and inpatient-only hospice care users (never-users, n = 8210). Information about hospice service utilization was collected from a web-based registry system. Patients were registered if they started to receive the hospice service after providing written informed consent during the pilot project from March 2016-July 2017. RESULTS: Most ever-users preferred to stay at home (84.0%), while never-users preferred hospital admission (66.9%). Most ever-users were enrolled in hospice by home care (78.9%) and used both home and inpatient care (72.4%). The overall duration of hospice care was significantly longer among ever-users than never-users (median 39 vs. 15 days, respectively; mean ± SD 59.6 ± 62.8 vs. 24.8 ± 32.1, respectively; p < .001). Participation in the pilot program improved bed utilization (p = .025) and turnover rate (p < .001) of inpatient hospice service. CONCLUSIONS: Home hospice care enabled early enrollment in hospice services and provided a valid option to patients who wished to stay at home. Policy efforts to facilitate home hospice care are needed.


Asunto(s)
Servicios de Atención de Salud a Domicilio/estadística & datos numéricos , Cuidados Paliativos al Final de la Vida/estadística & datos numéricos , Hospitales para Enfermos Terminales/estadística & datos numéricos , Neoplasias/terapia , Cuidados Paliativos/métodos , Anciano , Femenino , Recursos en Salud , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos
3.
J Org Chem ; 81(23): 11706-11715, 2016 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-27800682

RESUMEN

Rhodium-catalyzed denitrogenative cyclization of (E)-ethyl 2-(1-alkyl and arylsulfonyl-1H-1,2,3-triazol-4-yl)-3-aryl acrylate generated from (E)-ethyl 2-benzylidenebut-3-ynoates and N-sulfonyl azides in the presence of a copper catalyst was developed for the synthesis of a large number of functionalized benzofulvenes. Moreover, the synthesis of benzofulvenes was demonstrated as a one-pot method through tandem copper-catalyzed [3 + 2] cycloaddition and rhodium-catalyzed denitrogenative cyclization from (E)-ethyl 2-benzylidenebut-3-ynoates and N-sulfonyl azides.

4.
J Org Chem ; 80(11): 5859-69, 2015 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-25940682

RESUMEN

A synthetic route to a wide range of 2-alkoxyaryl-2-aryl enamines is developed from Rh-catalyzed alkoxyarylation of N-sulfonyl-4-aryl-1,2,3-triazoles with aryl ethers via the elimination of nitrogen molecule. In addition, 2-alkoxyaryl-2-aryl enamines are prepared via tandem Cu-catalyzed cycloaddition and Rh-catalyzed alkoxyarylation starting from alkynes, N-sulfonyl azides, and aryl ethers in one-pot.

5.
Beilstein J Org Chem ; 10: 1220-1227, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24991271

RESUMEN

We report an efficient Pd-catalyzed C(sp(2))-H activation/C-O bond formation for the synthesis of ethoxy dibenzooxaphosphorin oxides from 2-(aryl)arylphosphonic acid monoethyl esters under aerobic conditions.

6.
J Org Chem ; 78(20): 10209-20, 2013 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-24028218

RESUMEN

An efficient and cost-effective ruthenium-catalyzed oxidative cyclization of phosphonic acid monoesters or phosphinic acids with alkynes has been developed for the synthesis of a wide range of phosphaisocoumarins in good to excellent yields under aerobic conditions. A multitude of arylphosphonic acid monoesters and arylphosphinic acids having electron-donating and -withdrawing groups were oxidatively cyclized. Various diarylacetylenes, dialkylacetylenes, and alkylarylacetylenes effectively underwent the ruthenium-catalyzed oxidative cyclization. A substrate possessing benzoic acid as well as a phenylphosphonic monoester moiety was smoothly cyclized with hex-3-yne to afford a compound having both isocoumarin and phosphaisocoumarin moieties. Alkenylphosphonic monoester afforded phosphorus 2-pyrone through oxidative cyclization with alkyne. Competition experiments between diaryl- and dialkylalkynes and between diarylacetylenes having p-methoxy and p-chloro groups gave results which showed that the present oxidative cyclizations were not affected by the electronic effects of alkynes. Mechanistic studies revealed C-H bond metalation to be the rate-limiting step.

7.
Lab Anim Res ; 39(1): 34, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38102726

RESUMEN

BACKGROUND: This study aimed to establish an image evaluation grading criteria for experimental stifle joint osteoarthritis (OA) in anterior cruciate ligament transection induced OA beagle dog models. The severity of OA was assessed using X-ray and computed tomography (CT) imaging. RESULTS: A total of 32 dogs (8 controls and 24 OA-induced dogs) were included in the study. The OA-induced group showed significantly higher manual joint palpation, gait analysis, and OA severity scores than the control group. Based on these two results, we calculated correlation coefficients. There was a strong positive correlation between manual joint palpation scores and OA severity on diagnostic imaging and between gait analysis scores and OA severity. CONCLUSIONS: The developed grading criteria based on radiographic evaluation correlated with clinical assessments. The study also employed CT imaging to enhance the accuracy and sensitivity of early-stage OA change detection in the stifle joint. However, further studies with larger sample sizes and multiple evaluators are recommended for the validation and generalizability of this grading system. These established image evaluation grading criteria can help evaluate and monitor the efficacy of interventions and changes in OA lesions in canine models.

8.
Org Lett ; 24(17): 3128-3133, 2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35467886

RESUMEN

We disclose an iridium(III)-catalyzed regioselective B(4)-H allenylation of o-carboranes from o-carborane acids and propargyl carbonates under ball-milling conditions. This study sheds light on a novel method to accomplish regioselective B(4)-allenylation of o-carborane that cannot be realized through conventional solution-based reactions. Control experiments, including solution, neat, microwave, and high-temperature reactions, reveal that the B(4)-H allenylation of o-carborane is unique for ball-milling conditions.

9.
Org Lett ; 23(2): 416-420, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33377789

RESUMEN

Described is the Ir-catalyzed cage B(4)-amidation of o-carboranes with dioxazolones by carboxylic acid-assisted B(4)-H bond activation under extremely mild conditions, affording amidated o-carboranes and amidated and methoxycarbonylated nido-carboranes through sequential B(4)-amidation, O-methylation, and B(3)-deboronation in one pot. Carboxylic acid used as a directing group after the cage B(4)-amidation is efficiently trapped by trimethylsilyldiazomethane instead of undergoing decarboxylation. Mechanism studies demonstrated that the O-methylation through trapping of acid occurred first, followed by the B(3)-deboronation.

10.
Org Lett ; 23(21): 8622-8627, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34662139

RESUMEN

Mechanochemistry was successfully applied to the functionalization of carboranes. The mechanochemical iridium(III)-catalyzed regioselective B(3)- and B(4)-amidation of unsubstituted o-carboranes with dioxazolones was developed. In addition, the mechanochemical iridium(III)-catalyzed regioselective B(4)-amidation of substituted o-carboranes was demonstrated. Because mechanochemical B-amidation proceeds smoothly without organic solvents or external heating, the present method is regarded as a sustainable and environmentally friendly surrogate for typical solvent-based reactions.

12.
Org Lett ; 19(3): 452-455, 2017 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-28093911

RESUMEN

A palladium-catalyzed propargyl substitution reaction of propargyl acetates with indium organothiolates is developed for the synthesis of multisubstituted allenyl sulfides. This procedure can be applied to the synthesis of multisubstituted furans and pyrroles via tandem palladium-catalyzed propargyl substitution and cycloisomerization reaction in one pot.

13.
Org Lett ; 17(4): 908-11, 2015 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-25644690

RESUMEN

Alkenylation of phosphacoumarins is developed from the reaction of phosphacoumarins with a variety of activated as well as nonactivated alkenes via aerobic oxidative Heck reactions. In addition, 3-alkenylphosphacoumarins undergo an inverse electron demand Diels-Alder reaction (IEDDA) with enamines in situ generated from ketone and pyrrolidine followed by 1,2-elimination and a dehydrogenation, producing fluorescent benzophosphacoumarins.


Asunto(s)
Alquenos/química , Cumarinas/síntesis química , Colorantes Fluorescentes/síntesis química , Catálisis , Cumarinas/química , Colorantes Fluorescentes/química , Cetonas/química , Estructura Molecular , Oxidación-Reducción
14.
Org Lett ; 16(11): 2930-3, 2014 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-24856076

RESUMEN

An efficient phosphaannulation by Pd-catalyzed carbonylation of C-H bonds of phosphonic and phosphinic acids for the synthesis of oxaphosphorinanone oxides is reported. These compounds are novel phosphorus heterocyclic scaffolds, thus opening a new avenue to sequential C-C/C-O bond formation in one pot.


Asunto(s)
Paladio/química , Ácidos Fosfínicos/química , Ácidos Fosforosos/química , Compuestos de Fósforo/química , Compuestos de Fósforo/síntesis química , Catálisis , Enlace de Hidrógeno , Estructura Molecular , Óxidos/química
15.
Chem Commun (Camb) ; 49(77): 8671-3, 2013 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-23949774

RESUMEN

Rhodium-catalyzed oxidative coupling reactions via C-H activation and annulation directed by phosphonamide and phosphinamide groups were developed under aerobic conditions, which produced benzazaphosphole 1-oxides and phosphaisoquinolin-1-oxides.

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