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Treatment of the benzylallene-internal alkynes with [RhCl(CO)2]2 effected a cycloisomerization via a Csp2-H bond activation to produce the tricyclo[9.4.0.03,8]pentadecapentaene skeleton. The reaction mechanism via formation of the rhodabicyclo[4.3.0] intermediates and s-bond metathesis between the Csp2-H bond on the benzene ring and the Csp2-RhIII bond was proposed. In addition, a plausible alternative mechanism for the previously reported cycloisomerization of the benzylallene-terminal alkynes could also be proposed. [ABSTRACT FROM AUTHOR]

The first total synthesis of (+)-sieboldine A was completed starting from 5-(p-methoxybenzyloxy)pentyne in 19 steps. The enantioselective Keck allylation provided the dienyne derivative, which was exposed to the Pauson-Khand conditions to afford the bicyclo[4.3.0]nonenone derivative with high stereoselectivity with an ee value of 93%. The following Ueno-Stork reaction formed the cis-hydrindane core with a quaternary carbon center. The late-stage Schmidt glycosylation led to the formation of the N-hydroxyazacyclononane ring. [ABSTRACT FROM AUTHOR]

Treatment of aryliron complexes [CpFe(CO)2Ar] with organolithium reagents RLi in THF affords the corresponding ketones RCOAr. The reaction, wherein the aryliron complexes serve as arylcarbonyl cation equivalents, would begin with nucleophilic addition of RLi to one of the carbonyl ligands to form acyliron [CpFe(CO)(RCO)Ar] without lithiation of the Cp ring. [ABSTRACT FROM AUTHOR]

Treatment of aryliron complexes [CpFe(CO)2Ar] with styrenes in boiling xylene affords the corresponding stilbenes. The aryliron complexes, which become active upon heating, serve as arylating agents in the reaction. [ABSTRACT FROM AUTHOR]

Transmetalation between [CpFe(CO)2I] and arylzinc reagents or arylboronic acids under palladium catalysis yields the corresponding aryliron complexes [CpFe(CO)2Ar]. The reactions offer easy and reliable accesses to a variety of [CpFe(CO)2Ar] species bearing a functionalized aryl group. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed transmetalation between [CpFe(CO) 2I] and aryl Grignard reagents emerges as a new method for the synthesis of [CpFe(CO) 2Ar]. The aryliron complexes thus formed are useful arylmetal reagents that become active upon oxidation or UV irradiation. [ABSTRACT FROM AUTHOR]

Transmetalation between [CpFe(CO)2I] and aryltin reagents in the presence of copper salts yields the corresponding aryliron complexes [CpFe(CO)2Ar]. The high functional group compatibility of this copper-mediated reaction enables us to obtain [CpFe(CO)2Ar] having an acetyl or formyl group, which cannot be prepared by the previous methods with arylzinc or arylboron reagents under palladium catalysis. [ABSTRACT FROM AUTHOR]

Purpose Pencil beam scanning offers excellent conformity, but is sensitive to organ motion. We conducted a simulation study to validate our rescanning approach in combination with gating in the irradiation of liver tumors. Materials and methods 4DCT imaging was performed under free-breathing conditions in 30 patients with hepatocellular carcinoma. Dose distributions for a two-field approach were calculated for layered phase controlled rescannings (PCR) under organ motion conditions. A total dose of 45 Gy(RBE) was delivered to respective field-specific target volumes (FTVs) in two fractions, each composed of two orthogonal uniform fields of 11.25 Gy(RBE) at beam angles of either 0° and 90° or 0° and 270°. The number of rescannings was changed from 1 to 10. Results Good dose conformity was achieved with 4x PCR or more, and over 95% of the prescribed dose was delivered to the CTV independent of the use of gating. D95, Dmax/min and dose homogeneity were similar with or without gating, whereas V10 dose to the liver as well as maximal doses to healthy tissue (esophagus and cord) were about 40% lower with gating. However, total time increased by about 50% with gating. Conclusions Gated rescanning provides good target coverage and homogeneity with maximal sparing of healthy tissue. Our results suggest that carbon-ion pencil beam scanning may soon be available for the safe treatment of liver tumors. [ABSTRACT FROM AUTHOR]

Abstract Purpose  Progress of the novel carbon ion radiotherapy (CIRT) in the treatment of cancers has created the need for a method to accurately evaluate the response. We investigated whether l-[11C]methyl-methionine (11C-methionine) uptake at pre- and post-CIRT could be an early response predictor in patients with pelvic recurrence of rectal cancer. Procedures   11C-Methionine-positron emission tomography (PET) was performed prospectively in 53 patients with pelvic recurrence of rectal cancer before CIRT, and 48 patients were performed 11C-methionine PET at 1 month after CIRT. 11C-Methionine tumor uptake was measured by the tumor to muscle ratio (T/M ratio). The T/M ratios were evaluated in relation to clinical outcomes such as local re-recurrence, distant metastasis, and survival. The response to CIRT was also judged by computed tomography (CT) and magnetic resonance imaging (MRI). 11C-Methionine PET judgment was compared with CT/MRI judgment regarding the relevance to clinical outcome. Results  Baseline T/M ratio was 5.27 ± 1.90 (mean ± SD) in patients without developing local re-recurrence and 7.66 ± 3.17 in patients with local re-recurrence (p = 0.023, Mann–Whitney U test). Post-CIRT T/M ratios were 3.10 ± 1.28 in patients without local re-recurrence and 6.15 ± 2.98 in patients with local re-recurrence (p = 0.006, Mann–Whitney U test). By Kaplan–Meier analysis with log-rank test, patients with a baseline T/M ratio of ≦7.6 or a post-CIRT T/M ratio of ≦5.0 had significant lower pelvic re-recurrence rate. However, the percent change (reduction rate) from baseline to post-CIRT T/M ratio did not have significant relation to pelvic re-recurrence. There were no significant differences between 11C-methionine results (baseline T/M ratio, post-CIRT T/M ratio and percent change) and other clinical parameters (distant metastasis and survival). Conclusion   11C-methionine-PET can be used for early prediction of local re-recurrence after CIRT. Because CIRT is local therapy, 11C-methionine-PET cannot predict distant metastasis or survival after CIRT. [ABSTRACT FROM AUTHOR]