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Herein, we report an unprecedented copper‐catalyzed highly enantio‐ and diastereoselective radical oxyboration of β‐substituted styrenes. The lynchpin of success is ascribed to the development of a late‐stage stereomutation strategy, which enables enantioenriched cis‐isomers among a couple of early‐generated diastereomers to be converted into trans‐isomer counterparts, thus fulfilling high diastereocontrol; while the degree of enantio‐differentiation is determined by the borocupration process of the C=C bond. This reaction provides an efficient protocol to access enantioenriched trans‐1,2‐ dioxygenation products. The value of this method has further been highlighted in a diversity of follow‐up stereospecific transformations and further modifying complex molecules. [ABSTRACT FROM AUTHOR]

NF1 is a tumor suppressor gene that negatively regulates Ras signaling. NF1 deficiency plays an important role in carcinogenesis. To investigate the frequency and clinical significance of NF1 mutation, we examined mutation status of NF1, TP53, LKB1 and RB1 in 704 surgically resected lung adenocarcinomas from East Asian patients using semiconductor‐based Ion Torrent sequencing platform. Common driver events, including mutations in EGFR, KRAS, HER2, BRAF, MET, and fusions affecting ALK, RET and ROS1, were also concurrently detected. The correlation between NF1 mutations and clinicomolecular features of patients was further evaluated. Among 704 patients, 42 NF1 mutations were found in 33 patients (33/704, 4.7%), including 14 patients harboring EGFR/NF1 comutations (14/33, 42.4%). Comparing with EGFR‐mutant patients, patients harboring NF1 mutations were closely associated with solid component subtype (p = 0.028). Comparing with KRAS mutations, NF1 mutations were found more common in female and never smokers (p = 0.003 and p = 0.004, respectively). Kaplan–Meier survival analysis revealed that patients harboring NF1 mutation had similar disease‐free survival (DFS) and overall survival (OS) with patients with KRAS mutation. Although frequently overlapped with EGFR mutation, patients harboring NF1 mutation had significantly shorter DFS (p = 0.019) and OS (p = 0.004) than patients with EGFR mutation. During follow‐up, one female patient with EGFR exon 19 deletion and NF1 Q1815X comutation showed poor response to EGFR TKIs (Gefitinib and Osimertinib) after disease relapse. In conclusion, NF1 mutations define a unique molecular and clinicopathologic subtype of lung adenocarcinoma. Examination of NF1 mutation may contribute to molecular subtyping and therapeutic intervention of lung adenocarcinoma. What's new? Mutations in the tumor suppressor gene NF1 can lead to cancer. Here, the authors sequenced DNA from 704 cancers to investigate the prevalence of NF1 mutations in lung adenocarcinomas from an East Asian population. Only 4.5% of patients had NF1 mutations, fewer than expected. This could reflect ethnic differences between Asian and Western populations, or perhaps NF1 mutations are less common in early stage disease. They compared the characteristics of NF1 mutated cancers with various other mutations, and identified unique clinical characteristics and outcomes associated with NF1. Identifying NF1 tumors could improve therapeutic decision making for these patients. [ABSTRACT FROM AUTHOR]

Abstract: The enantioselective reduction of α‐hydroxy ketones with catecholborane has been developed employing 5 mol% of an 1,1′‐bi‐2‐naphthol (BINOL)‐derived ion‐pair organocatalyst. This methodology provides a straightforward access to the corresponding aromatic 1,2‐diols in high yields (up to 90%) with excellent enantioselectivities (up to 97%). Furthermore, the α‐amino ketones also could be reduced with moderate ee values under mild reaction condition. [ABSTRACT FROM AUTHOR]

A rhodium(II)/chiral phosphoric acid system has been developed for the asymmetric catalytic insertion of α-diazo esters into the O-H bond of carboxylic acids to generate an array of synthetically useful α-hydroxy ester derivatives in good ee (up to 95% ee). Furthermore, the substrate scope could be successfully extended to a range of phenols and alcohols with high yield (up to 92%) and excellent enantioselectivity (up to 97%) under mild reaction conditions. Additionally, a density functional theory (DFT) study was performed to elucidate the reaction mechanism. [ABSTRACT FROM AUTHOR]

A highly efficient and enantioselective hydrogenation of diversely substituted C=N-containing heterocyclic compounds such as 3-aryl-1,4-benzoxazines and 2-arylquinolines was experimentally explored by using 1,1′-spirobiindane-7,7′-diol-derived chiral phosphoric acids as the catalyst. This method provides straightforward access to the corresponding tetrahydroquinolines and dihydro-2 H-1,4-benzothiazines in high yields (85-99 %) with excellent enantioselectivities (91-99 %). The attractive features of this procedure, which include mild reaction conditions, operational simplicity, relatively low catalyst loading (1 mol-%), and high levels of enantioselectivities, make it a useful approach for the practical synthesis of optically active nitrogen-containing aromatic heterocycles. [ABSTRACT FROM AUTHOR]

Hydrogenation of C=N-containing heterocycles is carried out by using 1,1′-spirobiindane-7,7′-diol-derived chiral phosphoric acids as the catalyst. [ABSTRACT FROM AUTHOR]

Objective/hypothesis: The distribution of gentamicin in the inner ear via the endolymphatic sac (ES) or round window (RW) routes was investigated., Study Design: Experimental study., Methods: A fluorescent gentamicin-Texas Red conjugate (GTTR) was adopted to visualize the gentamicin. Adult guinea pigs were treated with GTTR applied to the ES or RW, the animals were allowed to recover for 3 days, then confocal microscopy was used to observe and quantify GTTR distributions in cochlear and vestibular sensory epithelium., Results: When GTTR was applied via the ES, strong GTTR labeling was observed in the vestibule while little GTTR was detected in the cochlea (P < .0001). However, distinct GTTR fluorescence was observed in the cochlea and vestibule following RW application (P = .7967). There was less GTTR labeling in cochlea via ES application than through RW administration (P < .0001)., Conclusions: ES drug application may be preferable for the treatment of intractable Meniere's disease. Laryngoscope, 2010.