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1.
J Org Chem ; 88(19): 14236-14241, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37729603

RESUMEN

This note discusses the application of a Minisci-type reaction for the direct alkylation of azoles with carboxylic acids as radical precursors. Different reaction conditions were investigated to achieve high yield of the desired products, focusing on acid strength and solvent screening. Moreover, the reactivity of imidazoles with various carboxylic acids was investigated, showing good yield for most cases. The study reveals the potential of this approach for late-stage functionalization in drug discovery.

2.
Chemistry ; 28(49): e202200818, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35666172

RESUMEN

Synergistic catalysis offers the unique possibility of simultaneous activation of both the nucleophile and the electrophile in a reaction. A requirement for this strategy is the stability of the active species towards the reaction conditions and the two concerted catalytic cycles. Since the beginning of the century, aminocatalysis has been established as a platform for the stereoselective activation of carbonyl compounds through HOMO-raising or LUMO-lowering. The burgeoning era of aminocatalysis has been driven by a deep understanding of these activation and stereoinduction modes, thanks to the introduction of versatile and privileged chiral amines. The aim of this review is to cover recent developments in synergistic strategies involving aminocatalysis in combination with organo-, metal-, photo-, and electro-catalysis, focusing on the evolution of privileged aminocatalysts architectures.


Asunto(s)
Aminas , Catálisis
3.
Angew Chem Int Ed Engl ; 61(47): e202209564, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-36111496

RESUMEN

The versatility of olefin metathesis is evident from its successful applications ranging from natural product synthesis to the valorization of renewable feedstocks. On the other side, flow chemistry has recently gained particular interest among the synthetic community, offering valuable alternatives to classic batch chemistry and paving the way to the development of new transformations. The application of continuous-flow methods to olefin metathesis represents one of the most promising evolutions in the field at the interface of industrially relevant synthesis and reactor engineering, significantly improving some of the typical problems such as undesired self-reactions and ethylene-mediated catalyst deactivation. This Minireview aims to provide a brief survey covering the major aspects of those techniques which we hope may be of interest for the chemical community as well as those interested in catalysis, continuous processing, enabling technologies and reactor design.


Asunto(s)
Productos Biológicos , Rutenio , Alquenos , Catálisis
4.
Chemistry ; 26(48): 10936-10947, 2020 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-32329534

RESUMEN

C-H activation has emerged as one of the most efficient tools for the formation of carbon-carbon and carbon-heteroatom bonds, avoiding the use of prefunctionalized materials. In spite of tremendous progress in the field, stoichiometric quantities of toxic and/or costly chemical redox reagents, such as silver(I) or copper(II) salts, are largely required for oxidative C-H activations. Recently, electrosynthesis has experienced a remarkable renaissance that enables the use of storable, safe and waste-free electric current as a redox equivalent. While major recent momentum was gained in electrocatalyzed C-H activations by 4d and 5d metals, user-friendly and inexpensive nickela-electrocatalysis has until recently proven elusive for oxidative C-H activations. Herein, the early developments of nickela-electrocatalyzed reductive cross-electrophile couplings as well as net-redox-neutral cross-couplings are first introduced. The focus of this Minireview is, however, the recent emergence of nickel-catalyzed electrooxidative C-H activations until April 2020.

5.
Angew Chem Int Ed Engl ; 59(32): 13490-13495, 2020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32348625

RESUMEN

A transition-metal-free carbon isotope exchange procedure on phenyl acetic acids is described. Utilizing the universal precursor CO2 , this protocol allows the carbon isotope to be inserted into the carboxylic acid position, with no need of precursor synthesis. This procedure enabled the labeling of 15 pharmaceuticals and was compatible with carbon isotopes [14 C] and [13 C]. A proof of concept with [11 C] was also obtained with low molar activity valuable for distribution studies.

6.
Am J Perinatol ; 36(S 02): S115-S119, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31238371

RESUMEN

BACKGROUND: The application of noninvasive ventilation (NIV) modalities from birth in the delivery room (DR) during fetal-neonatal transition reduces the need for invasive mechanical ventilation, mortality, and bronchopulmonary dysplasia (BPD). The use of a RAM nasal cannula (RAM NC) in the DR for resuscitation results in less need for intubation, chest compressions, and epinephrine administration when compared with using a face mask for PPV in the DR. OBJECTIVE: To evaluate the need for endotracheal intubation in the DR among extremely low gestational age neonates treated at birth with sustained inflation (SI) followed by a nasal continuous positive airway pressure (NCPAP) (range: 6-8 cm of H2O) delivered through the RAM NC. STUDY DESIGN: A retrospective study was conducted to compare the use of NIV techniques in the DR and the need for intubation in the DR in premature infants 23 to 28 weeks' gestational age from December 2016 to July 2018 (group A). These data were compared with those of premature inborn infants with similar GA born between April 2015 and November 2016 (group B). In the DR, immediately after birth, neonates in group A received SI through RAM NC followed by CPAP ranging from 6 to 8 cm H2O, whereas the neonates in group B were treated in the DR with SI administered through a face mask followed by the application of CPAP of 5 cm H2O delivered through a nasopharyngeal tube. RESULTS: A total of 65 preterm infants 23 to 28 weeks of gestational age, 31 in group A and 34 in group B, were included in the study. The percentage of neonates intubated in the DR was significantly lower in group A (p < 0.008). In both groups, no neonates died in the DR, and no one required epinephrine and/or chest compressions. For those neonates who did not require intubation in the DR, there was no significant difference in the average FiO2 on arrival in the neonatal intensive care unit, rate of intubation within 24 hours, and use of surfactant. The incidence of BPD was similar in the two groups. Only one infant in group A developed moderate BPD, and no one needed oxygen and/or ventilatory assistance at discharge. Mortality was similar in the two groups, with a slight prevalence in group B (27.7 vs. 19.2%). CONCLUSION: SI with RAM NC followed by NCPAP ranging from 6 to 8 cm H2O, administered with RAM NC resulted in a significant reduction of intubation in the DR.


Asunto(s)
Cánula , Presión de las Vías Aéreas Positiva Contínua , Recien Nacido Extremadamente Prematuro , Ventilación no Invasiva/métodos , Resucitación/métodos , Salas de Parto , Femenino , Edad Gestacional , Humanos , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro , Intubación Intratraqueal , Masculino , Máscaras , Estudios Retrospectivos
7.
Am J Perinatol ; 35(6): 561-565, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29694997

RESUMEN

Lactoferrin is one of the most represented and important bioactive proteins in human and mammal milk. In humans, lactoferrin is responsible for several actions targeting anti-infective, immunological, and gastrointestinal domains in neonates, infants, and young children. Evidence-based data vouch for the ability of supplemented lactoferrin to prevent sepsis and necrotizing enterocolitis in preterm infants and to reduce the burden of morbidity related to gastrointestinal and respiratory pathogens in young children. However, several issues remain pending regarding answers and clarification related to quality control, correct intakes, optimal schedules and schemes of supplementations, interactions with probiotics, and different types of milk and formulas. This review summarizes the current evidence regarding lactoferrin and discusses the areas in need of further guidance prior to the adoption of strategies that include a routine use of lactoferrin in neonates and young children.


Asunto(s)
Antiinfecciosos/uso terapéutico , Suplementos Dietéticos , Enfermedades del Prematuro/prevención & control , Lactoferrina/uso terapéutico , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Ensayos Clínicos Controlados Aleatorios como Asunto
8.
J Labelled Comp Radiopharm ; 61(13): 988-1007, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29926506

RESUMEN

Heterocycles play an essential role in modern pharmaceutical and agrochemical developments, representing a very common structural unit in marketed drugs. Over the 46 new drugs approved in 2017 by the FDA, 25 contain in their structure a heterocyclic core. The development of novel and straightforward labeling strategies for the effective insertion of carbon isotopes into heterocylic scaffolds is an inspiring and vibrant field of research. The use of carbon-11, carbon-13, and carbon-14 isotopes is well established in life science and particularly in pharmaceutical and agrochemical industry. Their introduction into small organic molecules represents a crucial step for the radiochemists. Because the labeling should occur in metabolically stable positions and in the shortest synthetic route, their incorporation into the heterocycles represents a viable solution. This review summarizes recent contributions to this area of research through the analysis of different industrial and academic cases.


Asunto(s)
Isótopos de Carbono/química , Compuestos Heterocíclicos/química , Marcaje Isotópico/métodos , Catálisis
9.
Minerva Pediatr ; 70(6): 579-588, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30334620

RESUMEN

Infants born prematurely before 37 weeks of gestational age (GA) have particular anatomical, immunological and metabolic characteristics that predispose them, even in the absence of diseases at birth, to severe morbidity. Respiratory syncytial virus (RSV) is the leading cause of hospitalization for lower respiratory tract infections (LRTI) in the first year of life, as well as an important cause of respiratory outcomes as recurrent wheezing in industrialized countries or mortality in developing countries. Prematurity is an important risk factor for hospitalization for severe RSV disease, but epidemiological, environmental and demographic risk factors also play a role in RSV infection. Currently, there is no effective antiviral therapy for the treatment of RSV infection, nor the possibility of using maternal immunization or vaccination of children to prevent infection, although numerous preclinical and clinical studies are still ongoing. Passive immunization with palivizumab has been shown to be safe and effective in preventing RSV hospitalization in children at greater risk of contracting a serious infection. Costs associated with palivizumab prophylaxis and its monthly intramuscularly administration has prompted many health institutions of different countries to implement specific recommendations, with the aim of protecting at risk infants for whom RSV infection is likely to cause serious illness or death. The cost-effectiveness ratio of prophylaxis, related to reduce hospitalization costs and the impact of the burden of RSV disease worldwide, greatly affects the drafting and the adoption of specific recommendations and the adherence to them, concerning the passive immunization with palivizumab.


Asunto(s)
Recien Nacido Prematuro , Palivizumab/administración & dosificación , Infecciones por Virus Sincitial Respiratorio/prevención & control , Animales , Antivirales/administración & dosificación , Antivirales/economía , Análisis Costo-Beneficio , Hospitalización/estadística & datos numéricos , Humanos , Recién Nacido , Palivizumab/economía , Infecciones por Virus Sincitial Respiratorio/economía , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/prevención & control , Infecciones del Sistema Respiratorio/virología , Factores de Riesgo
10.
Angew Chem Int Ed Engl ; 57(31): 9744-9748, 2018 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-29862657

RESUMEN

A robust, click-chemistry-inspired procedure for radiolabeling of cyclic ureas was developed. This protocol, suitable for all carbon isotopes (11 C, 13 C, 14 C), is based on the direct functionalization of carbon dioxide: the universal building block for carbon radiolabeling. The strategy is operationally simple and reproducible in different radiochemistry centers, exhibits remarkably wide substrate scope with short reaction times, and demonstrates superior reactivity as compared to previously reported systems. With this procedure, a variety of pharmaceuticals and an unprotected peptide were labeled with high radiochemical efficiency.


Asunto(s)
Dióxido de Carbono/química , Marcaje Isotópico , Radiofármacos/síntesis química , Urea/síntesis química , Isótopos de Carbono , Química Clic , Estructura Molecular , Radiofármacos/química , Urea/análogos & derivados , Urea/química
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