We report here a deallylative β-acylalkylation reaction of allylbenzene derivatives with allyl alcohols in the presence of Cp*Rh catalysts. Allylbenzenes possessing pyridyl and pyrazolyl directing groups were converted to β-aryl ketones via the cleavage of C(aryl)-C(allyl) bonds. Synthesis of a quinoline derivative from a β-aryl ketone product bearing a pyrazolyl group was also achieved.
View Article and Find Full Text PDFBackground And Purpose: To minimize cognitive decline without increasing brain tumor recurrence (BTR) by reduced-dose whole-brain radiotherapy (RD-WBRT) (25 Gy, 10 fractions) + stereotactic radiosurgery (SRS) in patients with ≤ 4 brain metastases.
Materials And Methods: Eligible patients with ≤ 4 brain metastases on contrast-enhanced MRI and Karnofsky Performance Status ≥ 70. The primary endpoint was the non-inferiority of BTR at distant sites in the brain (BTR-distant)-free survival at 6 months compared to that of the standard dose (SD)-WBRT (30 Gy, 10 fractions) + SRS arm in a randomized clinical trial (JROSG99-1) of SRS with/without SD-WBRT.
Angew Chem Int Ed Engl
January 2021
High-valent cyclopentadienyl cobalt catalysis is a versatile tool for sustainable C-H bond functionalizations. To harness the full potential of this strategy, control of the stereoselectivity of these processes is necessary. Herein, we report highly enantioselective intermolecular carboaminations of alkenes through C-H activation of N-phenoxyamides catalyzed by Co -complexes equipped with chiral cyclopentadienyl (Cp ) ligands.
View Article and Find Full Text PDFA method for catalytic conversion of C(aryl)-C(alkenyl) bonds in styrene derivatives to new C-C bonds is developed. In the presence of a rhodium catalyst, the alkenyl groups of styrenes bearing a pyrazolyl directing group were efficiently converted to other carbon substituents upon reacting with various alkenes including styrenes, aliphatic alkenes, and allyl alcohols. It is also indicated that the C-C bond cleavage proceeded via a hydrometalation/β-carbon elimination pathway.
View Article and Find Full Text PDFA method for the synthesis of N-arylpyrazoles by palladium-catalyzed coupling of aryl triflates with pyrazole derivatives is described. Using tBuBrettPhos as a ligand, the palladium-catalyzed C-N coupling of a variety of aryl triflates including ortho-substituted ones with pyrazole derivatives proceeded efficiently to give N-arylpyrazole products in high yields. 3-Trimethylsilylpyrazole was found to be an excellent pyrazole substrate for the coupling, and the corresponding product, 1-aryl-3-trimethylsilylpyrazole, also served as a great template for the syntheses of N-arylpyrazole derivatives, as demonstrated by regioselective halogenation at the 3-, 4-, and 5-positions of the pyrazole ring.
View Article and Find Full Text PDFJ Am Chem Soc
August 2018
This is a report of a single-institution prospective study evaluating the safety of a spot-scanning dedicated, small 360-degree gantry, synchrotron-based proton beam therapy (PBT) system. Data collection was performed for 56 patients with 59 treatment sites who received proton beam therapy at Hokkaido University Hospital between March 2014 and July 2015. Forty-one patients were male and 15 were female.
View Article and Find Full Text PDFIntroduction: We retrospectively evaluated the efficacy of three-dimensional conformal radiotherapy (3D-CRT) for spinal schwannoma.
Methods: Nine patients with spinal schwannoma were treated with 3D-CRT. All patients had a paravertebral or intraosseous component.
We report here a method for direct catalytic introduction of simple α-acylalkyl groups via rhodium-catalyzed C-H functionalization with cyclic alkenyl carbonates, synthetic equivalents to enolates bearing leaving groups. The reaction proceeded smoothly without using bases to give α-aryl ketones in high yields. Various nitrogen-containing aromatic rings and amide groups serve as directing groups.
View Article and Find Full Text PDFA 55-year-old woman underwent radiosurgery for a left cerebral hemisphere arteriovenous malformation (AVM) and developed radiation-induced necrosis causing a massive edema in the surrounding brain tissues. Despite various therapies, the edema expanded to the ipsilateral hemisphere and induced neurological symptoms. The radiation-induced necrotic lesion was surgically removed 4 years after radiosurgery.
View Article and Find Full Text PDFBackground: Olfactory neuroblastoma (ONB) is a rare tumor originating from olfactory epithelium. Here we retrospectively analyzed the long-term treatment outcomes and toxicity of radiotherapy for ONB patients for whom computed tomography (CT) and three-dimensional treatment planning was conducted to reappraise the role of radiotherapy in the light of recent advanced technology and chemotherapy.
Methods: Seventeen patients with ONB treated between July 1992 and June 2013 were included.
To investigate whether the neurocognitive function at 4 months could be a relevant primary endpoint in clinical trials dealing with brain metastases, we created a Japanese neurocognitive battery and examined the changes in patients' neurocognitive function for 1 year after their brain radiotherapy. In this prospective pilot study, we enrolled 27 patients (20 patients who received whole-brain radiation therapy [WBRT] and seven who received stereotactic irradiation [STI] alone) between March 2009 and December 2010. The follow-up neurocognitive data at 4, 8 and 12 months were available in 22 (17 WBRT, 5 STI), 19 patients (14 WBRT, 5 STI) and 13 patients (9 WBRT, 4 STI), respectively.
View Article and Find Full Text PDFBackground: The aim of our study was to analyze changes over time in the characteristics, treatment, and outcome of patients with primary central nervous system lymphoma (PCNSL).
Methods: Data on 315 patients with histologically proven PCNSL undergoing radiotherapy between 2005 and 2009 were collected from 20 Japanese institutions using a questionnaire. These data were then compared with data on 273 patients treated during the period 1995-2004 and those on 466 patients treated during the period 1985-1994.
A major problem of current cancer research and therapy is prediction of tumor recurrence after initial treatment, rather than the simple biological characterization of the malignancy and proliferative properties of tumors. Breast conservation therapy (BCT) is a well-approved, standard treatment for patients with early stages of breast cancer, which consists of lumpectomy and whole-breast irradiation. In spite of extensive studies, only 'age' and 'Ki-67 positivity' have been identified to be well correlated with local recurrence after BCT.
View Article and Find Full Text PDFBackground: In-room cone-beam computerized tomography (CBCT) imaging is a promising method to reduce setup errors, especially in organs such as the bladder that often have large intrafractional variations due to organ movement. CBCT image quality is limited by low contrast and imaging artifacts, but few data have been reported about inter-observer variability of bladder boundary delineation on CBCT. The aim of this work was to analyze and evaluate the inter-observer contouring uncertainties of bladder boundary delineation on CBCT images in a prospective fashion.
View Article and Find Full Text PDFJ Comput Assist Tomogr
March 2013
Objective: This study aimed to compare the diagnostic performance in the detection of brain metastases between contrast-enhanced T1-weighted volume isotropic turbo spin echo acquisition (T1-VISTA) and 3-dimensional T1-weighted fluid-attenuated inversion recovery (3D-T1-FLAIR) imaging at 3 T.
Methods: Two neuroradiologists selected 129 true (metastases) and 70 false (vessels and artifacts) lesions on the contrast-enhanced T1-VISTA and 3D-T1-FLAIR images of 14 cancer patients with hyperintense brain lesions. Four blinded neuroradiologists distinguished between the true and false lesions, using a 5-point confidence rating scale.
Int J Radiat Oncol Biol Phys
February 2013
Purpose: The effect of transient tumor expansion after conventionally fractionated stereotactic radiation therapy (SRT) on the symptomatic outcomes is not well-known.
Methods And Materials: This study enrolled 201 consecutive patients who received SRT for vestibular schwannoma. A conventional fractionation schedule was applied in 194 patients (97%), and 142 (71%) received a total dose of 50 Gy.
Two glioblastoma multiforme patients underwent (18)F-FMISO (fluoromisonidazole) positron emission tomography study to access the tumor oxygenation status before and immediately after fractionated radiotherapy concomitant with temozolomide chemotherapy. In both cases, a prominent (18)F-FMISO tumor accumulation observed in the first study was notably decreased in the second study, which was supposed to be a reoxygenation of the tumor. As far as we investigated, this is the first report of the changes of oxygenation status in glioblastoma multiforme treated through radiation therapy with temozolomide.
View Article and Find Full Text PDFObjective: To investigate the outcome of linac-based fractionated stereotactic radiotherapy over the last 10 years for intracranial skull base benign meningiomas in patients who were inoperable, who had residual tumors with some components of high mitotic index after surgery and who experienced relapse of the tumor.
Methods: Twenty-seven patients with intracranial skull base benign meningiomas treated with fractionated stereotactic radiotherapy were retrospectively reviewed. Twenty-seven cases were diagnosed as benign meningiomas on pathological (17 cases) or radiological (10 cases) examination.
Objective: Several recent studies have shown that oligometastatic disease has curative potential, although it was previously considered to signal a patient's last stage of life. Stereotactic body radiotherapy has been available for extra-cranial metastases in addition to stereotactic cranial radiotherapy for brain metastases. The aim of the present study was to retrospectively evaluate the clinical outcomes of stereotactic radiotherapy for patients with oligometastatic lesions.
View Article and Find Full Text PDFInt J Radiat Oncol Biol Phys
June 2010
Purpose: To evaluate the effectiveness of the stereotactic body frame (SBF), with or without a diaphragm press or a breathing cycle monitoring device (Abches), in controlling the range of lung tumor motion, by tracking the real-time position of fiducial markers.
Methods And Materials: The trajectories of gold markers in the lung were tracked with the real-time tumor-tracking radiotherapy system. The SBF was used for patient immobilization and the diaphragm press and Abches were used to actively control breathing and for self-controlled respiration, respectively.
Int J Radiat Oncol Biol Phys
December 2009
Purpose: Although the effectiveness of stereotactic radiosurgery for nonacoustic schwannomas is currently being assessed, there have been few studies on the efficacy of stereotactic radiotherapy (SRT) for these tumors. We investigated the long-term outcome of SRT for nonacoustic intracranial nerve schwannomas.
Methods And Materials: Seventeen patients were treated between July 1994 and December 2006.
Int J Radiat Oncol Biol Phys
March 2006
Background: To reduce the uncertainty of registration for lung tumors, we have developed a four-dimensional (4D) setup system using a real-time tumor-tracking radiotherapy system.
Methods And Materials: During treatment planning and daily setup in the treatment room, the trajectory of the internal fiducial marker was recorded for 1 to 2 min at the rate of 30 times per second by the real-time tumor-tracking radiotherapy system. To maximize gating efficiency, the patient's position on the treatment couch was adjusted using the 4D setup system with fine on-line remote control of the treatment couch.