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1.
N Engl J Med ; 390(13): 1176-1185, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38598572

RESUMEN

BACKGROUND: Lixisenatide, a glucagon-like peptide-1 receptor agonist used for the treatment of diabetes, has shown neuroprotective properties in a mouse model of Parkinson's disease. METHODS: In this phase 2, double-blind, randomized, placebo-controlled trial, we assessed the effect of lixisenatide on the progression of motor disability in persons with Parkinson's disease. Participants in whom Parkinson's disease was diagnosed less than 3 years earlier, who were receiving a stable dose of medications to treat symptoms, and who did not have motor complications were randomly assigned in a 1:1 ratio to daily subcutaneous lixisenatide or placebo for 12 months, followed by a 2-month washout period. The primary end point was the change from baseline in scores on the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part III (range, 0 to 132, with higher scores indicating greater motor disability), which was assessed in patients in the on-medication state at 12 months. Secondary end points included other MDS-UPDRS subscores at 6, 12, and 14 months and doses of levodopa equivalent. RESULTS: A total of 156 persons were enrolled, with 78 assigned to each group. MDS-UPDRS part III scores at baseline were approximately 15 in both groups. At 12 months, scores on the MDS-UPDRS part III had changed by -0.04 points (indicating improvement) in the lixisenatide group and 3.04 points (indicating worsening disability) in the placebo group (difference, 3.08; 95% confidence interval, 0.86 to 5.30; P = 0.007). At 14 months, after a 2-month washout period, the mean MDS-UPDRS motor scores in the off-medication state were 17.7 (95% CI, 15.7 to 19.7) with lixisenatide and 20.6 (95% CI, 18.5 to 22.8) with placebo. Other results relative to the secondary end points did not differ substantially between the groups. Nausea occurred in 46% of participants receiving lixisenatide, and vomiting occurred in 13%. CONCLUSIONS: In participants with early Parkinson's disease, lixisenatide therapy resulted in less progression of motor disability than placebo at 12 months in a phase 2 trial but was associated with gastrointestinal side effects. Longer and larger trials are needed to determine the effects and safety of lixisenatide in persons with Parkinson's disease. (Funded by the French Ministry of Health and others; LIXIPARK ClinicalTrials.gov number, NCT03439943.).


Asunto(s)
Antiparkinsonianos , Agonistas Receptor de Péptidos Similares al Glucagón , Enfermedad de Parkinson , Péptidos , Humanos , Antiparkinsonianos/administración & dosificación , Antiparkinsonianos/efectos adversos , Antiparkinsonianos/uso terapéutico , Personas con Discapacidad , Método Doble Ciego , Trastornos Motores/tratamiento farmacológico , Enfermedad de Parkinson/tratamiento farmacológico , Péptidos/administración & dosificación , Péptidos/efectos adversos , Péptidos/uso terapéutico , Resultado del Tratamiento , Agonistas Receptor de Péptidos Similares al Glucagón/administración & dosificación , Agonistas Receptor de Péptidos Similares al Glucagón/efectos adversos , Agonistas Receptor de Péptidos Similares al Glucagón/uso terapéutico , Progresión de la Enfermedad , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/efectos adversos , Fármacos Neuroprotectores/uso terapéutico , Inyecciones Subcutáneas
2.
Mov Disord ; 39(3): 618-622, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38291616

RESUMEN

BACKGROUND: Acting on the main target of dopaminergic cells, the striatal γ-aminobutyric acid (GABA)-ergic cells, might be a new way to treat persons with Parkinson's disease (PD). OBJECTIVE: The objective of this study was to assess the efficacy of bumetanide, an Na-K-Cl cotransporter (NKCC1) inhibitor, to improve motor symptoms in PD. METHODS: This was a 4-month double-blind, randomized, parallel-group, placebo-controlled trial of 1.75 to 3 mg/day bumetanide as an adjunct to levodopa in 44 participants with PD and motor fluctuations. RESULTS: Compared to the baseline, the mean change in OFF Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III score after 4 months of treatment (primary endpoint) did not improve significantly compared with placebo. No changes between participants treated with bumetanide and those treated with placebo were observed for most other outcome measures. Despite no relevant safety signals, bumetanide was poorly tolerated. CONCLUSIONS: There was no evidence in this study that bumetanide has efficacy in improving motor symptoms of PD. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/tratamiento farmacológico , Antiparkinsonianos , Bumetanida/uso terapéutico , Levodopa/uso terapéutico , Evaluación de Resultado en la Atención de Salud , Método Doble Ciego , Resultado del Tratamiento
3.
N Engl J Med ; 389(19): 1753-1765, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37937777

RESUMEN

BACKGROUND: Local injections of botulinum toxin type A have been used to treat essential head tremor but have not been extensively studied in randomized trials. METHODS: In a multicenter, double-blind, randomized trial, we assigned, in a 1:1 ratio, adult patients with essential or isolated head tremor to receive botulinum toxin type A or placebo. Botulinum toxin or placebo was injected under electromyographic guidance into each splenius capitis muscle on the day of randomization (day 0) and during week 12. The primary outcome was improvement by at least 2 points on the Clinical Global Impression of Change (CGI) scale at week 6 after the second injection (week 18 after randomization). The CGI scale was used to record the patient's assessment of the degree of improvement or worsening of head tremor since baseline; scores range from 3 (very much improved) to -3 (very much worse). Secondary outcomes included changes in tremor characteristics from baseline to weeks 6, 12, and 24. RESULTS: A total of 120 patients were enrolled; 3 patients were excluded during screening, and 117 patients were randomly assigned to receive botulinum toxin (62 patients) or placebo (55 patients) and were included in the intention-to-treat analysis. Twelve patients in the botulinum toxin group and 2 patients in the placebo group did not receive injections during week 12. The primary outcome - improvement by at least 2 points on the CGI scale at week 18 - was met by 31% of the patients in the botulinum toxin group as compared with 9% of those in the placebo group (relative risk, 3.37; 95% confidence interval, 1.35 to 8.42; P = 0.009). Analyses of secondary outcomes at 6 and 12 weeks but not at 24 weeks were generally supportive of the primary-outcome analysis. Adverse events occurred in approximately half the patients in the botulinum toxin group and included head and neck pain, posterior cervical weakness, and dysphagia. CONCLUSIONS: Injection of botulinum toxin into each splenius capitis muscle on day 0 and during week 12 was more effective than placebo in reducing the severity of isolated or essential head tremor at 18 weeks but not at 24 weeks, when the effects of injection might be expected to wane, and was associated with adverse events. (Funded by the French Ministry of Health; Btx-HT ClinicalTrials.gov number, NCT02555982.).


Asunto(s)
Toxinas Botulínicas Tipo A , Temblor Esencial , Fármacos Neuromusculares , Temblor , Adulto , Humanos , Toxinas Botulínicas Tipo A/administración & dosificación , Toxinas Botulínicas Tipo A/efectos adversos , Toxinas Botulínicas Tipo A/uso terapéutico , Método Doble Ciego , Temblor Esencial/tratamiento farmacológico , Cabeza , Resultado del Tratamiento , Temblor/tratamiento farmacológico , Electromiografía/métodos , Inyecciones Intramusculares/métodos , Cefalea/inducido químicamente , Dolor de Cuello/inducido químicamente , Fármacos Neuromusculares/administración & dosificación , Fármacos Neuromusculares/efectos adversos , Fármacos Neuromusculares/uso terapéutico
4.
J Neurol ; 270(12): 6033-6043, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37648911

RESUMEN

BACKGROUND: Longitudinal measures of structural brain changes using MRI in relation to clinical features and progression patterns in PD have been assessed in previous studies, but few were conducted in well-defined and large cohorts, including prospective clinical assessments of both motor and non-motor symptoms. OBJECTIVE: We aimed to identify brain volumetric changes characterizing PD patients, and determine whether regional brain volumetric characteristics at baseline can predict motor, psycho-behavioral and cognitive evolution at one year in a prospective cohort of PD patients. METHODS: In this multicentric 1 year longitudinal study, PD patients and healthy controls from the MPI-R2* cohort were assessed for demographical, clinical and brain volumetric characteristics. Distinct subgroups of PD patients according to motor, cognitive and psycho-behavioral evolution were identified at the end of follow-up. RESULTS: One hundred and fifty PD patients and 73 control subjects were included in our analysis. Over one year, there was no significant difference in volume variations between PD and control subjects, regardless of the brain region considered. However, we observed a reduction in posterior cingulate cortex volume at baseline in PD patients with motor deterioration at one year (p = 0.017). We also observed a bilateral reduction of the volume of the amygdala (p = 0.015 and p = 0.041) and hippocampus (p = 0.015 and p = 0.053) at baseline in patients with psycho-behavioral deterioration, regardless of age, dopaminergic treatment and center. CONCLUSION: Brain volumetric characteristics at baseline may predict clinical trajectories at 1 year in PD as posterior cingulate cortex atrophy was associated with motor decline, while amygdala and hippocampus atrophy were associated with psycho-behavioral decline.


Asunto(s)
Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/complicaciones , Estudios Longitudinales , Estudios Prospectivos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Atrofia/patología
5.
Neuroimage Clin ; 36: 103231, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36279753

RESUMEN

Several postmortem studies have shown iron accumulation in the substantia nigra of Parkinson's disease patients. Iron concentration can be estimated via MRI-R2∗ mapping. To assess the changes in R2∗ occurring in Parkinson's disease patients compared to controls, a multicentre transversal study was carried out on a large cohort of Parkinson's disease patients (n = 163) with matched controls (n = 82). In this study, 44 patients and 11 controls were removed due to motion artefacts, 21 patient and 6 controls to preserve matching. Thus, 98 patients and 65 age and sex-matched healthy subjects were selected with enough image quality. The study was conducted on patients with early to late stage Parkinson's disease. The images were acquired at 3Tesla in 12 clinical centres. R2∗ values were measured in subcortical regions of interest (substantia nigra, red nucleus, striatum, globus pallidus externus and globus pallidus internus) contralateral (dominant side) and ipsilateral (non dominant side) to the most clinically affected hemibody. As the observed inter-subject R2∗ variability was significantly higher than the disease effect, an original strategy (intrasubject subcortical quantitative referencing, ISQR) was developed using the measurement of R2∗ in the red nucleus as an intra-subject reference. R2∗ values significantly increased in Parkinson's disease patients when compared with controls; in the substantia nigra (SN) in the dominant side (D) and in the non dominant side (ND), respectively (PSN_D and PSN_ND < 0.0001). After stratification into four subgroups according to the disease duration, no significant R2∗ difference was found in all regions of interest when comparing Parkinson's disease subgroups. By applying our ISQR strategy, R2(ISQR)∗ values significantly increased in the substantia nigra (PSN_D and PSN_ND < 0.0001) when comparing all Parkinson's disease patients to controls. R2(ISQR)∗ values in the substantia nigra significantly increased with the disease duration (PSN_D = 0.01; PSN_ND = 0.03) as well as the severity of the disease (Hoehn & Yahr scale <2 and ≥ 2, PSN_D = 0.02). Additionally, correlations between R2(ISQR)∗ and clinical features, mainly related to the severity of the disease, were found. Our results support the use of ISQR to reduce variations not directly related to Parkinson's disease, supporting the concept that ISQR strategy is useful for the evaluation of Parkinson's disease.


Asunto(s)
Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico por imagen , Sustancia Negra/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Núcleo Rojo , Hierro
6.
Parkinsonism Relat Disord ; 103: 34-41, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36030666

RESUMEN

INTRODUCTION: There is a growing interest in personality evaluation in Parkinson's disease (PD), following observations of specific temperaments in PD patients. Therefore, our objective was to evaluate personality dimensions from the Temperament and Character Inventory (TCI) in a cohort of fluctuating PD patients considered for deep brain stimulation. METHODS: Fluctuating PD patients from the PREDISTIM cohort were included. Description of TCI dimensions and comparison with a French normative cohort were performed. Pearson correlations between TCI dimensions and motor, behavioral and cognitive variables were investigated. Structural and internal consistency analysis of the TCI were further assessed. RESULTS: The 570 PD patients presented significant higher scores in Harm Avoidance, Reward Dependence, Persistence, Self-Directedness and Cooperativeness and significant lower scores in Self-Transcendence compared to the French normative cohort; only Novelty Seeking scores were not different. Harm Avoidance and Self-directedness scores were correlated with PDQ-39 total, HAMD, HAMA scores, and anxiolytic/antidepressant treatment. Novelty Seeking scores were correlated with impulsivity. Pearson correlations between TCI dimensions, principal component analysis of TCI sub-dimensions and Cronbach's alpha coefficients showed adequate psychometric proprieties. CONCLUSION: The TCI seems to be an adequate tool to evaluate personality dimensions in PD with good structural and internal consistencies. These fluctuating PD patients also have specific personality dimensions compared to normative French population. Moreover, Harm Avoidance and Self-Directedness scores are associated with anxio-depressive state or quality of life and, and Novelty Seeking scores with impulsivity.


Asunto(s)
Ansiolíticos , Enfermedad de Parkinson , Humanos , Temperamento , Inventario de Personalidad , Enfermedad de Parkinson/diagnóstico , Calidad de Vida , Determinación de la Personalidad , Antidepresivos
7.
BMJ Open ; 9(1): e022720, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30782684

RESUMEN

OBJECTIVES: We tested the hypothesis that stroke outcomes in patients with preadmission use of benzodiazepine are worse. METHOD: In a prospective cohort study, we recruited patients with acute ischaemic stroke. Mortality, functional outcomes and cognition were evaluated at 8 and 90 days after stroke. RESULTS: 370 patients were included. 62 (18.5%) of the 336 remaining patients were treated with benzodiazepines when stroke occurred, and they did not receive any other psychotropic drug. The mortality rate was higher in benzodiazepines users than non-users at day 8 (2.2% vs 8.1%, p=0.034) and day 90 (8.1% vs 25.9%, p=0.0001). After controlling for baseline differences using propensity-score matching, only the difference in mortality rate at day 90 was of borderline of significance, with a matched OR of 3.93 (95% CI, 0.91 to 16.98). In propensity-score-adjusted cohort, this difference remained significant with a similar treatment effect size (adjusted OR, 3.50; 95% CI, 1.57 to 7.76). A higher rate of poor functional outcome at day 8 and day 90 defined bymodified Rankin scale (mRS) ≥2 or by theBarthel index (BI) <95 was found in benzodiazepines users. In propensity-score-adjusted cohort, only the difference in mRS≥2 at day 90 remained significant (adjusted OR, 1.89; 95% CI, 1.02 to 3.48). In survivors at day 8 and at day 90, there was no significant difference in cognitive evaluation. CONCLUSION: Our study has shown that preadmission use of benzodiazepines could be associated with increased post-stroke mortality at 90 days. These findings do not support a putative neuroprotective effect of γ-aminobutyric acidA receptors agonists and should alert clinicians of their potential risks. TRIAL REGISTRATION NUMBER: NCT00763217.


Asunto(s)
Antipsicóticos/uso terapéutico , Benzodiazepinas/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/mortalidad , Anciano , Anciano de 80 o más Años , Causas de Muerte , Femenino , Francia , Humanos , Tiempo de Internación , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Puntaje de Propensión , Estudios Prospectivos , Factores de Tiempo
8.
Neurology ; 90(23): e2059-e2067, 2018 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-29752303

RESUMEN

OBJECTIVE: To delineate the natural history, diagnosis, and treatment response of Parkinson disease (PD) in individuals with 22q11.2 deletion syndrome (22q11.2DS), and to determine if these patients differ from those with idiopathic PD. METHODS: In this international observational study, we characterized the clinical and neuroimaging features of 45 individuals with 22q11.2DS and PD (mean follow-up 7.5 ± 4.1 years). RESULTS: 22q11.2DS PD had a typical male excess (32 male, 71.1%), presentation and progression of hallmark motor symptoms, reduced striatal dopamine transporter binding with molecular imaging, and initial positive response to levodopa (93.3%). Mean age at motor symptom onset was relatively young (39.5 ± 8.5 years); 71.4% of cases had early-onset PD (<45 years). Despite having a similar age at onset, the diagnosis of PD was delayed in patients with a history of antipsychotic treatment compared with antipsychotic-naive patients (median 5 vs 1 year, p = 0.001). Preexisting psychotic disorders (24.5%) and mood or anxiety disorders (31.1%) were common, as were early dystonia (19.4%) and a history of seizures (33.3%). CONCLUSIONS: Major clinical characteristics and response to standard treatments appear comparable in 22q11.2DS-associated PD to those in idiopathic PD, although the average age at onset is earlier. Importantly, treatment of preexisting psychotic illness may delay diagnosis of PD in 22q11.DS patients. An index of suspicion and vigilance for complex comorbidity may assist in identifying patients to prioritize for genetic testing.


Asunto(s)
Síndrome de DiGeorge/complicaciones , Síndrome de DiGeorge/diagnóstico , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico , Adulto , Antiparkinsonianos/uso terapéutico , Bases de Datos Bibliográficas/estadística & datos numéricos , Estimulación Encefálica Profunda , Síndrome de DiGeorge/mortalidad , Síndrome de DiGeorge/terapia , Femenino , Humanos , Cooperación Internacional , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/mortalidad , Enfermedad de Parkinson/terapia , Índice de Severidad de la Enfermedad , Distribución por Sexo , Estadísticas no Paramétricas , Tetrabenazina/análogos & derivados , Tetrabenazina/metabolismo , Tomografía Computarizada de Emisión de Fotón Único
9.
Mult Scler ; 24(9): 1256-1258, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29676204

RESUMEN

Brain MRI was originally considered to appear normal in neuromyelitis optica spectrum disorders (NMO-SD). Typical brain lesions are now well described and have been integrated in the latest revision of NMO-SD criteria, but the NMO-SD MRI pattern remains not yet comprehensive. We report here extensive white matter lesions (EWML) mimicking leukodystrophy in a 50-year-old woman with long-lasting anti-AQP4+ NMO-SD. We suggest that EWML could be a possible brain MRI presentation of NMO-SD patients.


Asunto(s)
Leucoencefalopatías/patología , Neuromielitis Óptica/patología , Sustancia Blanca/patología , Encefalopatías/diagnóstico por imagen , Encefalopatías/patología , Diagnóstico Diferencial , Femenino , Humanos , Leucoencefalopatías/diagnóstico por imagen , Imagen por Resonancia Magnética , Persona de Mediana Edad , Neuromielitis Óptica/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen
10.
Fundam Clin Pharmacol ; 32(2): 227-233, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29143369

RESUMEN

The aim of this study was to assess an automated detection method of serious adverse reactions induced by oral targeted therapy (OTT) in patients with cancer, performed in the French Diagnosis Related Groups (DRG) database. Patients with cancer of the Poitiers hospital who started an OTT between 2014 and 2015 were included. This study focused on adverse drug reaction which required inpatient hospitalization (ADRh ). All diagnoses coded in the DRG database for hospital stays that occurred within 3 months after OTT initiation were collected (potential ADRh ). Filters (exclusion criteria) were automatically applied on potential ADRh to exclude diagnoses that were not adverse drug reactions (false positives). A pharmacovigilance review was carried out to identify ADRh in the medical records (reported ADRh ). The sensitivity and specificity of the detection method were estimated for each filter combinations by comparison between potential and reported ADRh . This study included 129 patients. The medical records review led to identify 19 ADRh (all coded in the DRG database) in 14 patients. To maintain a 100% sensitivity of the method detection, the best specificity obtained was 58.3% (95% IC: [55.2-61.4]).The use of restrictive filters ('drug' in the diagnostic label, specific diagnosis code for adverse cancer drug reaction) resulted in a 97.8% specificity (95% IC: [96.6-98.5]) with a 38.2% sensitivity (95% IC: [23.9-55.0]). Our method has detected the third of ADRh with an excellent specificity. Complementary experimentations in pharmacovigilance centers are necessary to evaluate the interest of this tool in routine in addition to spontaneous reporting.


Asunto(s)
Antineoplásicos/efectos adversos , Minería de Datos/métodos , Grupos Diagnósticos Relacionados , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/diagnóstico , Terapia Molecular Dirigida/efectos adversos , Administración Oral , Anciano , Antineoplásicos/administración & dosificación , Automatización , Bases de Datos Factuales , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/terapia , Femenino , Francia/epidemiología , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Farmacovigilancia , Factores de Tiempo
11.
Fundam Clin Pharmacol ; 31(2): 237-244, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27736027

RESUMEN

Progressive multifocal leukoencephalopathy (PML) is an often fatal demyelinating disease of the central nervous system. As effective treatment is unavailable, identification of all drugs that could be associated with PML is essential. The objective of this study was to investigate the putative association of reports of PML and drugs. We used the case/noncase method in the French PharmacoVigilance database (FPVD). Cases were reports of PML in the FPVD between January 2008 and December 2015. Noncases were all other reports during the same period. To assess the association between PML and drug intake, we calculated an adverse drug report odds ratio (ROR) with its 95% confidence interval. We have studied the delay of onset of PML for each drug concerned. Among the 101 cases of PML, 39 drugs were mentioned as suspect. The main therapeutic classes suspected with significant ROR were antineoplastic agents (n = 85), immunosuppressants (n = 67), and corticosteroids. A latent interval from the time of drug initiation to the development of PML is established: the median time to onset was 365 days (123-1095 days). The onset of PML is highly variable and differs among drug classes [from 1 to 96 months (IQR: 39.0-126)]. An association between PML and some immunosuppressant drugs was found as expected, but also with antineoplastic agents and glucocorticoids. An important delay of PML onset after stopping treatment is suspected and should alert prescribers. Prescribers but also patients should be informed about the potential associations with all these drugs. Monitoring could be necessary for many drugs to early detect PML.


Asunto(s)
Sistemas de Registro de Reacción Adversa a Medicamentos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Leucoencefalopatía Multifocal Progresiva/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Bases de Datos Factuales , Femenino , Francia/epidemiología , Glucocorticoides/efectos adversos , Humanos , Inmunosupresores/efectos adversos , Leucoencefalopatía Multifocal Progresiva/inducido químicamente , Masculino , Persona de Mediana Edad , Farmacovigilancia , Factores de Tiempo
13.
JAMA Neurol ; 72(10): 1209, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26457635
14.
Magn Reson Chem ; 52(6): 273-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24652706

RESUMEN

Pyridylmethylamines or pma are versatile platforms for different catalytic transformations. Five pma-ligands and their respective Pd complexes have been studied by liquid state NMR. By comparing (1)H, (13)C and (15)N chemical shifts for each pma/pma-Pd couple, a general trend for the metallacycle atoms concerns variations of the electronic distribution at the pendant arm, especially at the nitrogen atom of the ligand. Moreover, the increase of the chemical shift of the pendant arm nitrogen atom from primary to tertiary amine is also related to the increase of crowding within the complex. This statement is in good agreement with X-ray data collected for several complexes. Catalytic results for the Suzuki-Miyaura reaction involving the pma-Pd complexes showed within this series that a sterically crowded and electron-rich ligand in the metallacycle was essential to reach the coupling product with a good selectivity. In this context, NMR study of chemical shifts of all active nuclei especially in the metallacycle could give a trend of reactivity in the studied family of pma-Pd complexes.

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