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1.
Angew Chem Int Ed Engl ; 63(7): e202317683, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38150265

RESUMO

Herein, we report the use of isonitriles as alkyl radical precursors in light-mediated hydro- and deuterodeamination reactions. The reaction is scalable, shows broad functional group compatibility and potential to be used in late-stage functionalization. Importantly, the method is general for Cα -primary, Cα -secondary and Cα -tertiary alkyl isonitriles. For most examples, high yields were obtained through direct visible-light irradiation of the isonitrile in the presence of a silyl radical precursor. Interestingly, in the presence of an organic photocatalyst (4CzIPN) a dramatic acceleration was observed. In-depth mechanistic studies using UV/Vis absorption, steady-state and time-resolved photoluminescence, and transient absorption spectroscopy suggest that the excited state of 4CzIPN can engage in a single-electron transfer with the isonitrile.

2.
Biomedicines ; 10(5)2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35625873

RESUMO

More than 1 billion people live in areas endemic for leishmaniasis, which is a relevant threat for public health worldwide. Due to the inadequate treatments, there is an urgent need to develop novel alternative drugs and to validate new targets to fight this disease. One appealing approach is the selective inhibition of protein kinases (PKs), enzymes involved in a wide range of processes along the life cycle of Leishmania. Several PKs, including glycogen synthase kinase 3 (GSK-3), have been validated as essential for this parasite by genetic or pharmacological methods. Recently, novel chemical scaffolds have been uncovered as Leishmania GSK-3 inhibitors with antiparasitic activity. In order to find new inhibitors of this enzyme, a virtual screening of our in-house chemical library was carried out on the structure of the Leishmania GSK-3. The virtual hits identified were experimentally assayed both for leishmanicidal activity and for in vitro inhibition of the enzyme. The best hits have a quinone scaffold. Their optimization through a medicinal chemistry approach led to a set of new compounds, provided a frame to establish biochemical and antiparasitic structure-activity relationships, and delivered molecules with an improved selectivity index. Altogether, this study paves the way for a systemic search of this class of inhibitors for further development as potential leishmanicidal drugs.

3.
Org Lett ; 23(19): 7434-7438, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34524833

RESUMO

We present a strategy for the synthesis of spirocyclic cyclobutanes with modulable exit vectors based on the regioselective monoborylation of spirocyclobutenes. Using an inexpensive copper salt and a commercially available bidentate phosphine, a broad variety of borylated spirocycles have been prepared with complete regiocontrol. The boryl moiety provides a synthetic handled for further functionalization, allowing access to a wide array of spirocyclic building blocks from a common intermediate.

4.
Angew Chem Int Ed Engl ; 60(21): 11763-11768, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33689223

RESUMO

The diastereo- and enantioselective diboration of spirocyclobutenes provides a platform for the rapid preparation of a wide variety of chiral spirocyclic building blocks. The chemoselective functionalization of the carbon-boron bond in the products, including a stereospecific sp3 -sp2 Suzuki-Miyaura cross-coupling reaction, provides a powerful tool to control the directionality and the nature of the exit vectors in the spirocyclic framework.

5.
Chimia (Aarau) ; 74(11): 852-856, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33243319

RESUMO

Herein we describe the reactivity found between vinyl epoxides and catalytically generated copper-boryl complexes. By tuning the substituents of the alkene and/or the reaction conditions, 1,4-diols, allylic alcohols or cyclopropylboronates can be prepared. The stereochemical information of the vinyl epoxide is transferred to the products with high levels of stereocontrol.

6.
Angew Chem Int Ed Engl ; 58(10): 3188-3192, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30600867

RESUMO

Herein, we report a catalytic and stereospecific method for the preparation of enantioenriched α-hydroxy cyclopropylboronates with control in four contiguous stereocenters. The reaction involves the borylation of readily available allylic epoxides using an inexpensive Cu(I) salt and a commercially available phosphine ligand. High diastereocontrol is achieved and different diastereomers can be selectively prepared. Functionalization of the carbon-boron bond provides access to different enantiomerically enriched trisubstituted cyclopropanes from a common intermediate.

7.
Acta méd. colomb ; 38(1): 32-35, ene.-mar. 2013. ilus, tab
Artigo em Espanhol | LILACS, COLNAL | ID: lil-677358

RESUMO

Se presenta el caso de un paciente en el cual ocurrieron dos manifestaciones clínicas consideradas inusuales y poco reportadas en la literatura, la ruptura esplénica espontánea y la ascitis quilosa. La enfermedad de base para estas presentaciones fue un linfoma esplénico de la zona marginal. Hacemos algunas consideraciones generales sobre estas dos presentaciones que deben tenerse en cuenta. (Acta Med Colomb 2013; 38: 32-35).


We report the case of a patient in which there were two clinical manifestations considered unusual and with few reported cases in the literature: spontaneous splenic rupture and chylous ascites. The underlying disease for these presentations was a splenic marginal zone lymphoma. We make some general observations on these two presentations that must be considered. (Acta Med Colomb 2013; 38: 32-35).


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Ruptura Esplênica , Ascite Quilosa , Literatura , Linfoma
8.
Rev. cuba. ortop. traumatol ; 23(1)ene.-jun. 2009.
Artigo em Espanhol | LILACS | ID: lil-581318

RESUMO

Las fracturas femorales periprotésicas son cada vez más comunes, aumentan según se incrementa el número de pacientes con artroplastia. Presentamos un caso de una paciente femenina de 73 años, con historia de colocación de prótesis parcial Thompson por fractura del cuello femoral izquierdo, desde aproximadamente 13 años. Después de una caída de sus pies, sufrió fractura periprotésica de fémur izquierdo tipo II de Johannsson, con vástago femoral estable. Se muestra mediante estudios radiológicos una variante de tratamiento quirúrgico, donde se utilizó una lámina recta AO y cerclajes de alambre. Con este tipo de proceder se obtuvo reducción y estabilidad de la fractura.


Periprosthetic femoral fractures are more and more common, increasing according to an increment in number of patients presenting with arthroplasty. Authors present the case of a female patient aged 73, with a placement history of a partial Thompson prosthesis from left femoral neck fracture approximately 13 years ago. After a spontaneous fall, she suffered a periprosthetic fracture of type II Hohannson in left femur with a stable femoral shaft. By radiological studies a surgical treatment variant is showed using a straight AO plate and wire tiring. Using this procedure it was possible to obtain reduction and stability of fracture.


De nos jours, les fractures fémorales sont de plus en plus fréquentes ; leur nombre s'élève au fur et à mesure que les arthroplasties augmentent. Nous présentons ici le cas d'une patiente âgée de 73 ans, qui porte depuis 13 ans environ une prothèse partielle Thompson due à une fracture du col fémoral gauche. Après tomber de ses propres pieds, elle a souffert une fracture périprothésique du fémur gauche type II de Johannsson. Les auteurs exposent au moyen des études radiologiques une variante du traitement chirurgical, dans lequel une lame droite AO et des cerclages en fil sont utilisés. Grâce à ce type de procédure, on a obtenu la réduction et la stabilité de cette fracture.

9.
Rev. cuba. ortop. traumatol ; 21(2)jul.-dic. 2007.
Artigo em Espanhol | LILACS | ID: lil-499408

RESUMO

Se realizó un estudio descriptivo retrospectivo de 508 pacientes mayores de 15 años con diagnóstico de fractura de cadera, ingresados en el Hospital Clínico Quirúrgico Docente Celia Sánchez Manduley de Manzanillo, en el período comprendido de enero de 2001 a diciembre de 2005. Se dio a conocer la incidencia en la morbilidad y mortalidad real en el medio cubano y se valoró el comportamiento de la relación ingreso hospitalario-acto quirúrgico de urgencia, así como las principales complicaciones posquirúrgicas de los pacientes geriátricos. El grupo más afectado resultó el de mujeres blancas en edades entre 81 y 90 años. Prevalecieron las fracturas del macizo trocantérico con 341 pacientes. Se realizó osteosíntesis en 85,9 por ciento de los casos intervenidos, con un alto porcentaje de uso de lámina angulada AO de 130o (63,9 por ciento). En el caso de las fracturas del cuello femoral (167) se prefierió realizar la osteosíntesis. Se efectuaron de urgencia 82,9 por ciento del total de las intervenciones quirúrgicas. Las complicaciones respiratorias y las metabólicas fueron las más frecuentes y como dato final falleció 4,1 por ciento de los pacientes.


A descriptive and retrospective study was conducted among 508 patients over 15 with a diagnosis of hip fracture admitted in Celia Sánchez Manduley Clinical and Surgical Teaching Hospital of Manzanillo from December 2002 to December 2005. The incidence on real morbidity and mortality in the Cuban environment was made known, and the behaviour of the admission-emergency surgery ratio was assessed, as well as the main postsurgical complications observed in the geriatric patients. The most affected group was that of white females aged 81-90. The trochanteric mass fracture prevailed with 341 patients. Osteosynthesis was performed in 85.9 percent of the operated on, with AO angular plate of 130o (63.9 percent). In the case of the fractures of the femoral neck (167) osteosynthesis was preferred. 82.9 percent of the operations carried out were emergency operations. The respiratory and metabolic complications were the most frequent. 4.1 percent of the patients died.


Assuntos
Humanos , Adolescente , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/mortalidade
10.
Rev. colomb. radiol ; 4(2): 63-6, mayo-ago. 1992. ilus
Artigo em Espanhol | LILACS | ID: lil-293667

RESUMO

La cateterización de la arteria umbilical es un procedimiento frecuentemente utilizado en las Unidades de Cuidado Intensivo Neonatal. A partir de 1970 se han reportado aneurismas aórticos como complicaciones de este procedimiento. En el presente artículo se describe el caso de un lactante menor a quien se diagnóstica mediante diferentes modalidades por imágen aneurisma de la aorta abdominal


Assuntos
Humanos , Recém-Nascido , Aneurisma Aórtico/etiologia , Aneurisma Infectado , Cateterismo Periférico , Artérias Umbilicais
12.
Rev. colomb. radiol ; 3(1): 21-32, abr. 1991. ilus
Artigo em Espanhol | LILACS | ID: lil-293637

RESUMO

Este artículo actualiza las indicaciones y aplicaciones de la ecografía en los pacientes pediátricos a la luz de los avances tecnológicos de éste método de imágen como son los transductores de alta resolución y la modalidad Doppler


Assuntos
Humanos , Pediatria , Ultrassom , Ultrassonografia
13.
Rev. colomb. radiol ; 2(1): 24-35, ene.-abr. 1990. ilus, graf
Artigo em Espanhol | LILACS | ID: lil-293619

RESUMO

En la presente actualización se describe la técnica de la ecografía doppler, se revisan sus fundamentos físicos, sus limitaciones y se señalan las múltiples aplicaciones de este método diagnóstico en la evaluación de las diferentes patologías pediátricas


Assuntos
Humanos , Criança , Pré-Escolar , Lactente , Pediatria , Ultrassonografia
14.
Rev. colomb. radiol ; 1(2): 34-8, sept.-dic. 1989. ilus
Artigo em Espanhol | LILACS | ID: lil-293611

RESUMO

Se presenta un paciente con aneurisma de la vena de Galeno diagnosticado mediante ultrasonido bifimensional y doppler pulsado. Estos estudios revelaron una masa anecoica intracraneana con flujo venoso y arterial, confirmando así los hallazgos clínicos de insuficiencia cardiaca congestiva. Se describe además la velocidad de flujo de esta estructura vascular anómala y los hallazgos radiológicos de dicha malformación


Assuntos
Humanos , Veias Cerebrais , Veias Cerebrais/anormalidades , Malformações Arteriovenosas Intracranianas , Ultrassom
15.
Rev. colomb. radiol ; 1(1): 7-27, mayo-ago. 1989. ilus, graf
Artigo em Espanhol | LILACS | ID: lil-293600

RESUMO

El presente artículo describe la utilidad del ultrasonido cerebral a través de la fontanela anterior, en el diagnóstico y seguimiento de anomalías congénitas, lesión anoxo-isquémica, hemorrágica intracraneana, patología infecciosa, tumores cerebrales y evaluación del tamaño ventricular


Assuntos
Humanos , Recém-Nascido , Lactente , Cérebro , Cérebro/anormalidades , Cérebro/anatomia & histologia , Ultrassom , Ultrassonografia
16.
In. Asociacion de Medicos del Hospital de la Misericordia; Universidad Nacional de Colombia. 3er Curso, 82 Aniversario, Hospital de la Misericordia: Presentacion de Casos Clinicos, Servicios Medicos y Quirurgicos. s.l, s.n, 1988. p.59-60.
Não convencional em Espanhol | LILACS | ID: lil-86478
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