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1.
Nat Commun ; 14(1): 4565, 2023 Jul 28.
Article in English | MEDLINE | ID: mdl-37507379

ABSTRACT

Direct functionalization of C(sp3)-H bonds allows rapid access to valuable products, starting from simple petrochemicals. However, the chemical transformation of non-activated methylene groups remains challenging for organic synthesis. Here, we report a general electrochemical method for the oxidation of C(sp3)-H and C(sp2)-H bonds, in which cyclic alkanes and (cyclic) olefins are converted into cycloaliphatic ketones as well as aliphatic (di)carboxylic acids. This resource-friendly method is based on nitrate salts in a dual role as anodic mediator and supporting electrolyte, which can be recovered and recycled. Reducing molecular oxygen as a cathodic counter reaction leads to efficient convergent use of both electrode reactions. By avoiding transition metals and chemical oxidizers, this protocol represents a sustainable oxo-functionalization method, leading to a valuable contribution for the sustainable conversion of petrochemical feedstocks into synthetically usable fine chemicals and commodities.

5.
AJR Am J Roentgenol ; 184(1): 169-74, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15615969

ABSTRACT

OBJECTIVE: The objective of this study was to describe MRI findings in patients with eosinophilic fasciitis (EF) and to correlate clinical and laboratory findings with the MRI findings. MATERIALS AND METHODS: Six patients with histologically proven EF underwent MRI at the time of diagnosis and after therapy (15 MRI examinations). Unenhanced T1-weighted, T2-weighted, and STIR sequences were performed using a 1.5-T MRI system. In addition, all patients were imaged with contrast-enhanced T1-weighted sequences. MRI findings, clinical findings, and laboratory parameters were retrospectively reviewed. RESULTS: At the time the six patients presented, all eight MRI examinations revealed symmetric thickening and hyperintensity of the superficial muscle fasciae of the thigh, calves, or arms on unenhanced T1-weighted, T2-weighted, or STIR sequences, with strong enhancement after administration of IV contrast agent. In seven of the eight MRI examinations, similar signal changes were also present in the deep muscle fasciae. After treatment, the fascial abnormalities found on MRI disappeared on six of eight MRI examinations performed in five patients-a rate that correlated well with the clinical findings. In one patient with EF involvement of the thigh, the MRI abnormalities showed partial remission, which also correlated well with the clinical findings. CONCLUSION: In EF, MRI reveals characteristic findings including thickening, signal abnormalities, and contrast enhancement of the superficial and, to a lesser extent, deep muscle fasciae. MRI is useful for establishing the diagnosis, guiding the choice of biopsy site, and assessing treatment response.


Subject(s)
Eosinophilia/diagnosis , Extremities , Fasciitis/diagnosis , Magnetic Resonance Imaging/methods , Soft Tissue Infections/diagnosis , Adult , Aged , Diagnosis, Differential , Eosinophilia/pathology , Fasciitis/pathology , Female , Humans , Male , Middle Aged , Retrospective Studies , Soft Tissue Infections/pathology
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