http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Addition, Substitution, and Ring-Contraction Reactions of Quinones with N-Heterocyclic Carbenes
Ping, Lucy,Bak, JungMin,Kim, Youngmee,Bouffard, Jean American Chemical Society 2018 Journal of organic chemistry Vol.83 No.16
<P>Despite the common use of quinones as oxidizing agents in N-heterocyclic carbene (NHC)-based organocatalysis and transition-metal catalysis, the direct reactivity of quinones with NHCs remains underexplored. In this paper, we report the reactivity of NHCs with common <I>p</I>- and <I>o</I>-quinones, uncovering three unreported reactions involving contractions of the quinone ring that lead to push-pull furanolactone chromophores, NHC fulvalenes, and α-acylimidazolium cyclopentenone derivatives. These experiments also provide a rationale for the superior compatibility of tetra-<I>tert</I>-alkylated diphenoquinones in NHC-based oxidative transformations.</P> [FIG OMISSION]</BR>
Geschwind, Jean-Franç,ois,Kudo, Masatoshi,Marrero, Jorge A.,Venook, Alan P.,Chen, Xiao-Ping,Bronowicki, Jean-Pierre,Dagher, Lucy,Furuse, Junji,de Guevara, Laura Ladró,n,Papandreou, Christo RADIOLOGICAL SOCIETY OF NORTH AMERICA 2016 Radiology Vol.279 No.2
<P>Purpose: To evaluate transarterial chemoembolization (TACE) use prior to and concomitantly with sorafenib in patients with unresectable hepatocellular carcinoma (HCC) across different global regions. Materials and Methods: GIDEON is an observational registry study of more than 3000 HCC patients. Patients with histologically, cytologically, or radiographically diagnosed HCC, and for whom a decision had been made to treat with sorafenib, were eligible. Patients were enrolled into the registry from 39 countries beginning in January 2009, with the last patient follow-up in April 2012. Detailed data on treatment history, treatment patterns, adverse events, and outcomes were collected. All treatment decisions were at the discretion of the treating physicians. Documented approval from local ethics committees was obtained, and all patients provided signed informed consent. Descriptive statistics, including minimum, median, and maximum, were calculated for metric data, and frequency tables for categorical data. Kaplan-Meier estimates with 95% confidence intervals were calculated for survival end points. Results: A total of 3202 patients were eligible for safety analysis, of whom 2631 (82.2%) were male. Median age was 62 years (range, 15-98 years). A total of 1511 (47.2%) patients underwent TACE prior to sorafenib; 325 (10.1%) underwent TACE concomitantly. TACE prior to sorafenib was more common in Japan and Asia- Pacific compared with all other regions (362 [71.3%] and 560 [60.3%] vs 12-209 [13.3%-37.1%]). Adverse events were reported in 2732 (85.3%) patients overall, with no notable differences in the incidence of adverse events, regardless of TACE treatment history. Overall survival was 12.7 months in prior-TACE patients, 9.2 months in non-prior-TACE patients, 21.6 months in concomitant-TACE patients, and 9.7 months in non-concomitant-TACE patients. Conclusion: Global variation exists in TACE use in sorafenib-treated HCC patients. The combination of TACE with sorafenib appears to be a well-tolerated and viable therapeutic approach. (C) RSNA, 2016</P>