ABSTRACT
A straightforward electrochemical protocol for efficient hydrogenation of unsaturated CîC bonds has been reported in an undivided cell. A series of versatile 1,4-diketones are smoothly generated under metal-free and external-reductant-free electrolytic conditions. Moreover, the tolerance of various functional groups and decagram-scale experiments have shown the practicability and potential applications of this methodology. Moreover, a range of heterocyclic compounds were easily prepared through follow-up procedures of 1,4-diketones.
ABSTRACT
The efficient electrochemically promoted [3 + 2] annulation of imidazo[1,2-a]pyridines with alkynes using traceless electrons as green reagents has been developed, leading to the synthesis of a large class of polycyclic heteroaromatics in good yields with a broad substrate scope under mild and green conditions. The scaled-up experiment, follow-up procedures, and potential biological applications show the practicability and feasibility of the electrochemical method.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the value of in vivo proton magnetic resonance spectroscopy (MRS) in the assessment of hepatocellular carcinoma (HCC) and monitor its metabolic change shortly after transcatheter arterial chemoembolization (TACE).</p><p><b>METHODS</b>In this prospective study, 28 consecutive patients with large HCC (> or = 3 cm in diameter) confirmed by fine needle aspiration biopsy were recruited. The 1H MRS of all hepatic lesions and some uninvolved liver parenchyma were performed with 1. 5T whole body MR scanner. Among them, 15 cases were evaluated again about one week after TACE. The main metabolites such as choline and lipid before and after interventional therapy were measured to assess the early response of the tumor.</p><p><b>RESULTS</b>The technical success rate of 1H MRS in liver was high (33/41, 80%), closely related to breath motion, location of lesion, and size of voxel. In spectra, the choline compound peak of HCC elevated compared with uninvolved liver parenchyma. After TACE, both the amplitude and the area of choline resonance peak significantly descended (choline-to-lipid ratios from 0.352 +/- 0.080 to 0.167 +/- 0.030, P = 0.026; from 0.205 +/- 0.060 to 0.070 +/-0.020, P = 0.042, respectively); yet lipid resonance peak ascended.</p><p><b>CONCLUSIONS</b>In vivo 1H MRS is technically feasible for the evaluation of large focal hepatic lesions, however, the reproducibility and stability are not as good as routine MR scan. 1H MRS can monitor the early stage metabolic changes of HCC after TACE but limitation like quantification still exists.</p>
