268 research outputs found
Conversion of Amides into Esters by the Nickel-Catalyzed Activation of Amide C-N Bonds
The amide function is ubiquitous in natural compounds as
well as in man-made molecules and materials. It is generally
very stable and poorly reactive owing to its resonance-stabilized
C–N group that imparts a planar geometry to amides.
In contrast, carboxylic esters are generally reactive under a
variety of mild conditions; therefore, it is not surprising that
a number of direct methods are available to the chemist for
converting esters into amides (amino-de-alkoxylation reaction)
but very few for achieving the opposite transformation.
Recently, Professors Neil Garg and Ken Houk from the University
of California, Los Angeles (UCLA, USA) reported in Nature
a groundbreaking method for converting amides into esters
with a high degree of efficiency
Bone metastases from renal cell carcinoma: patient survival after surgical treatment
<p>Abstract</p> <p>Background</p> <p>Surgery is the primary treatment of skeletal metastases from renal cell carcinoma, because radiation and chemotherapy frequently are not effecting the survival. We therefore explored factors potentially affecting the survival of patients after surgical treatment.</p> <p>Methods</p> <p>We retrospectively reviewed 101 patients operatively treated for skeletal metastases of renal cell carcinoma between 1980 and 2005. Overall survival was calculated using the Kaplan-Meier method. The effects of different variables were evaluated using a log-rank test.</p> <p>Results</p> <p>27 patients had a solitary bone metastasis, 20 patients multiple bone metastases and 54 patients had concomitant visceral metastases. The overall survival was 58% at 1 year, 37% at 2 years and 12% at 5 years. Patients with solitary bone metastases had a better survival (p < 0.001) compared to patients with multiple metastases. Age younger than 65 years (p = 0.036), absence of pathologic fractures (p < 0.001) and tumor-free resection margins (p = 0.028) predicted higher survival. Gender, location of metastases, time between diagnosis of renal cell carcinoma and treatment of metastatic disease, incidence of local recurrence, radiation and chemotherapy did not influence survival.</p> <p>Conclusions</p> <p>The data suggest that patients with a solitary metastasis or a limited number of resectable metastases are candidates for wide resections. As radiation and chemotherapy are ineffective in most patients, surgery is a better option to achieve local tumor control and increase the survival.</p
Multidirectional Synthesis of Substituted Indazoles via Iridium-Catalyzed C–H Borylation
A Heterogeneous Nickel Catalyst for the Hydrogenolysis of Aryl Ethers without Arene Hydrogenation
A Scalable and Expedient Route to 1-Aza[6]helicene Derivatives and Its Subsequent Application to a Chiral-Relay Asymmetric Strategy
5 Prognostic impact of intensive local therapy to bone lesions in renal cell carcinoma patients with bone metastasis
206 Prognostic significance of sarcopenia in metastatic renal cell carcinoma: Its association with survival benefit from cytoreductive nephrectomy
Coagulation of particles in oil by an a.c. electric field (observation of the coagulation process under various mechanical conditions)
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