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1.
RSC Adv ; 13(46): 32077-32082, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37920755

RESUMO

A general protocol for the europium-catalyzed rearrangement of aryl-pentadienyl-ethers is described. The mode of rearrangement and product formation in this reaction was solely determined by the aryl substituent para to the phenol. If the para-position is occupied by a substituent, the substrate undergoes a [3,3] rearrangement to the ortho-position to form a prochiral branched diene. In turn, a free para-position in the starting material allows the reaction to proceed via a [5,5] rearrangement and leads to a linear conjugated diene product. The severely underdeveloped and synthetically valuable [5,5] rearrangement was investigated in terms of scope and mechanism.

2.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 3): 177-181, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36909998

RESUMO

The two substituted 1,2,3,4-tetra-hydro-naphthalenes, methyl (R)-3-{(1R,4S)-6-meth-oxy-4,7-dimethyl-5,8-bis-[(triiso-propyl-sil-yl)-oxy]-1,2,3,4-tetra-hydro-naph-th-al-en-1-yl}butano-ate, C36H66O5Si2, (2), and methyl (E)-3-{(1R,4S)-8-hy-droxy-6-meth-oxy-4,7-dimethyl-5-[(triiso-propyl-sil-yl)-oxy]-1,2,3,4-tetra-hydro-naphthalen-1-yl}acrylate, C26H42O5Si, (8), crystallize in the Sohncke space groups P212121 and P21, respectively, with the absolute structure determined on the basis of anomalous dispersion effects. The configurations of the stereo centres in the 1,2,3,4-tetra-hydro-naphthalene moiety of (2) and (8) are the same, and the conformation of the non-aromatic part of the ring system is nearly identical. In the crystal of (2), weak non-classical C-H⋯O inter-actions consolidate the packing, whereas in (8), inter-molecular O-H⋯O hydrogen-bonding inter-actions of medium-to-weak strength direct the mol-ecules into Z-shaped strands extending parallel to [010].

3.
J Org Chem ; 87(22): 15333-15349, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36283031

RESUMO

We describe our efforts toward the total synthesis of the natural product elisabethin A. The first route was guided by the proposed biosynthesis, assembling the 6,6-ring system before forming the five-membered ring including the quaternary carbon. The second approach includes a high yielding cyclization under Mitsunobu conditions as a key step. It allowed the preparation of an unusual and highly functionalized bicyclic 6,5-spiro compound. Both routes share a common advanced precursor obtained from an "underdeveloped" Claisen rearrangement of an aryl dienyl ether.


Assuntos
Diterpenos , Compostos de Espiro , Estereoisomerismo , Ciclização
4.
Pathogens ; 10(6)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200808

RESUMO

BACKGROUND: Dialister pneumosintes (D. pneumosintes) is known to cause dental, periodontal or sinus infections. To date, the pathogen has only been described in a small number of cases with a severe infection. CASE REPORT: We describe the clinical case of a 13-year-old, obese female patient that presented with acute respiratory failure and sepsis. A CT-scan showed extensive bilateral patchy areas, subpleural and peribronchovascular consolidations with surrounding ground-glass opacity, extensive consolidations in the lower lobes of both lungs matching to a severe pneumonia and clinically emerging acute respiratory distress syndrome. Moreover, it showed extensive sinusitis of the right sinus frontalis, maxillaris and right cellulae ethmoidales. D. pneumosintes was isolated from an anaerobic blood culture obtained at admission. The antibiotic treatment included piperacillin/tazobactam and oral switch to ampicillin/sulbactam plus ciprofloxacin. CONCLUSIONS: We describe the first adolescent with severe systemic D. pneumosintes infection. Since the pathogen is difficult to culture the systemic virulence remains unclear. This work aims to sensitize health care specialists to consider D. pneumosintes infection in patients with periodontal or sinusal infection.

5.
J Neural Transm (Vienna) ; 128(3): 305-314, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33146753

RESUMO

Non-motor symptoms (NMS) occur in patients with cervical dystonia (CD) but with variable frequencies and impact on health-related quality of life (HRQoL). To define non-motor and motor profiles and their respective impact on HRQoL in CD patients using the newly validated Dystonia Non-Motor Symptoms Questionnaire (DNMSQuest). In an observational prospective multicentre case-control study, we enrolled 61 patients with CD and 61 age- and sex-matched healthy controls (HC) comparing demographic data, motor and non-motor symptoms and HRQoL measurements. 95% CD patients reported at least one NMS. Mean total NMS score was significantly higher in CD patients (5.62 ± 3.33) than in HC (1.74 ± 1.52; p < 0.001). Pain, insomnia and stigma were the most prevalent NMS and HRQoL was significantly impaired in CD patients compared to HC. There was strong correlation of NMS burden with HRQoL (CDQ-24: r = 0.72, EQ-5D: r = - 0.59; p < 0.001) in CD patients. Regression analysis between HRQoL and NMS suggested that emotional well-being (standardized beta = - 0.352) and pain (standardized beta = - 0.291) had a major impact on HRQoL while, in contrast motor severity had no significant impact in this model. Most NMS with the exception of pain, stigma and ADL did not correlate with motor severity. NMS are highly prevalent in CD patients and occur independent of age, sex, disease duration, duration of botulinum neurotoxin therapy and socio-economic status. Specific NMS such as emotional well-being and pain have a major impact on HRQoL and are more relevant than motor severity.


Assuntos
Qualidade de Vida , Torcicolo , Estudos de Casos e Controles , Humanos , Dor , Estudos Prospectivos
6.
Ann Clin Transl Neurol ; 6(10): 2054-2065, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31560179

RESUMO

OBJECTIVE: To develop and validate a novel 14-item self-completed questionnaire (in English and German) enquiring about the presence of non-motor symptoms (NMS) during the past month in patients with craniocervical dystonia in an international multicenter study. METHODS: The Dystonia Non-Motor Symptoms Questionnaire (DNMSQuest) covers seven domains including sleep, autonomic symptoms, fatigue, emotional well-being, stigma, activities of daily living, sensory symptoms. The feasibility and clinimetric attributes were analyzed. RESULTS: Data from 194 patients with CD (65.6% female, mean age 58.96 ± 12.17 years, duration of disease 11.95 ± 9.40 years) and 102 age- and sex-matched healthy controls (66.7% female, mean age 55.67 ± 17.62 years) were collected from centres in Germany and the UK. The median total NMS score in CD patients was 5 (interquartile range 3-7), significantly higher than in healthy controls with 1 (interquartile range 0.75-2.25) (P < 0.001, Mann-Whitney U-test). Evidence for intercorrelation and convergent validity is shown by moderate to high correlations of total DNMSQuest score with motor symptom severity (TWSTRS: rs  = 0.61), clinical global impression (rs  = 0.40), and health-related quality of life measures: CDQ-24 (rs  = 0.74), EQ-5D index (rs  = -0.59), and scale (rs  = -0.49) (all P < 0.001). Data quality and acceptability was very satisfactory. INTERPRETATION: The DNMSQuest, a patient self-completed questionnaire for NMS assessment in CD patients, appears robust, reproducible, and valid in clinical practice showing a tangible impact of NMS on quality of life in CD. As there is no specific, comprehensive, validated tool to assess the burden of NMS in dystonia, the DNMSQuest can bridge this gap and could easily be integrated into clinical practice.


Assuntos
Psicometria/instrumentação , Psicometria/normas , Torcicolo/diagnóstico , Torcicolo/fisiopatologia , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Inquéritos e Questionários/normas , Torcicolo/psicologia
7.
Angew Chem Int Ed Engl ; 55(36): 10886-9, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27392232

RESUMO

Mixtures of alkyllithium and heavier alkali-metal alkoxides are often used to form alkyl compounds of heavier alkali metals, but these mixtures are also known for their high reactivity in deprotonative metalation reactions. These organometallic mixtures are often called LiC-KOR superbases, but despite many efforts their constitution remains unknown. Herein we present mixed alkali-metal alkyl/alkoxy compounds produced by reaction of neopentyllithium with potassium tert-butoxide. The key to success was the good solubility and temperature-stability of neopentyl alkali-metal compounds, leading to hexane-soluble mixtures, which allowed handling at ambient temperatures and isolation by crystallization. The compounds in solid state and in solution were identified by X-ray crystallography and NMR spectroscopy as mixtures of lithium/potassium neopentyl/tert-butoxy aggregates of varying compositions Lix Ky Npz (OtBu)x+y-z .

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