Herein, we report a manganese-catalyzed three-component coupling of H containing alcohols, methanol, and phosphines for the synthesis of γ-hydroxy phosphines via a borrowing hydrogen strategy. In this development, methanol serves as a sustainable C1 source. A variety of aromatic and aliphatic substituted alcohols and phosphines could undergo the dehydrogenative cross-coupling process efficiently and deliver the corresponding β-phosphinomethylated alcohol products in moderate to good yields.
View Article and Find Full Text PDFA homogeneous manganese-catalyzed cross-coupling of two secondary alcohols for the divergent synthesis of γ-disubstituted alcohols and β-disubstituted ketones is reported. Employing the well-defined Mn-MACHO as the catalyst, this novel protocol has a broad substrate scope with good functional group tolerance and affords a diverse library of valuable disubstituted alcohols and ketones in moderate to good yields. The strong influence of the reaction temperature on the selective formation of alcohol products was theorized in preliminary DFT studies.
View Article and Find Full Text PDFBackground: Multifocal (MF) and multicentric (MC) breast cancer cases have been increasingly diagnosed owing to the extensive use of improved preoperative breast imaging. The current tumor-node-metastasis staging system uses the dimension of the largest tumor and recommends reporting the pathological features of the largest tumor in MF/MC breast cancers.
Aim: This study aimed to explore whether the largest or aggregate dimensions of MF and MC breast cancers can better predict tumor behavior.
Aesthetic Plast Surg
December 2022
Background: Gynecomastia (GYN) is the most common benign disease in males. A vacuum-assisted biopsy is a minimally invasive surgical technique for GYN treatment that achieves satisfactory aesthetic results. However, due to the operation under non-direct vision, it is difficult to localize the bleeding points and assess the residual glandular tissue.
View Article and Find Full Text PDFEpilepsy is a disorder of abnormal brain activity typified by spontaneous and recurrent seizures. MicroRNAs (miRNAs) are short non-coding RNAs, critical for the post-transcriptional regulation of gene expression. MiRNA dysregulation has previously been implicated in the induction of epilepsy.
View Article and Find Full Text PDFNitrate contamination in surface water has become an environmental problem widespread concern. In this study, environmental isotopes (δ(15)N-NO3 (-) and δ(18)O-NO3 (-)) and the chemical compositions of water samples from an urban river in Chongqing, China, were analyzed to evaluate the primary sources of nitrate pollution. A Bayesian isotope mixing model was applied to estimate the relative contributions of five potential NO3 (-) sources to river pollution (sewage/manure, soil N, NH4 (+) in fertilizer and precipitation, NO3 (-) fertilizer, and NO3 (-) in precipitation).
View Article and Find Full Text PDFLand use and ecosystem services need to be assessed simultaneously to better understand the relevant factors in sustainable land management. This paper analyzed land use changes in the middle reach of the arid Heihe River Basin in northwest China over the last two decades and their impacts on water resources and soil organic carbon (SOC) storage. The results indicated that from 1986 to 2007: (1) cropland and human settlements expanded by 45.
View Article and Find Full Text PDFMany spatial interpolation methods perform well for gentle terrains when producing spatially continuous surfaces based on ground point data. However, few interpolation methods perform satisfactorily for complex terrains. Our objective in the present study was to analyze the suitability of several popular interpolation methods for complex terrains and propose an optimal method.
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