Copper-Catalyzed Regio- and Enantioselective Hydroboration of Difluoroalkyl-Substituted Internal Alkenes.

Catalytic asymmetric hydroboration of fluoroalkyl-substituted alkenes is a straightforward approach to access chiral small molecules possessing both fluorine and boron atoms. However, enantioselective hydroboration of fluoroalkyl-substituted alkenes without fluorine elimination has been a long-standing challenge in this field. Herein, a copper-catalyzed hydroboration of difluoroalkyl-substituted internal alkenes with high levels of regio- and enantioselectivities is reported. The native carbonyl directing group, copper hydride system, and bisphosphine ligand play crucial roles in suppressing the undesired fluoride elimination. This atom-economic protocol provides a practical synthetic platform to obtain a wide scope of enantioenriched secondary boronates bearing the difluoromethylene moieties under mild conditions. Synthetic applications including functionalization of biorelevant molecules, versatile functional group interconversions, and preparation of difluoroalkylated Terfenadine derivative are also demonstrated.

Diffuse midline glioma with H3K27 alteration in adults: a clinicopathological analysis / 中华病理学杂志

Objective: To investigate the clinicopathological characteristics, pathological diagnosis and prognosis of diffuse midline glioma (DMG) with H3K27 alteration in adults. Methods: Twenty cases of H3K27-altered adult DMG diagnosed in the First Affiliated Hospital of Nanjing Medical University were enrolled from 2017 to 2022. All cases were evaluated by clinical and imaging presentations, HE, immunohistochemical staining and molecular genetics; and the relevant literature was reviewed. Results: The ratio of male to female was 1∶1, and the median age was 53 years (range from 25 to 74 years); the tumors were located in the brainstem (3/20, 15%) and non-brainstem (17/20, 85%; three in thoracolumbar spinal cord and one in pineal region). The clinical manifestations were non-specific, mostly dizziness, headache, blurred vision, memory loss, low back pain, limb sensation and/or movement disorders, etc. Microscopically, the tumors showed infiltrative growth, with WHO grade 2 (3 cases), grade 3 (12 cases), and grade 4 (5 cases). The tumors showed astrocytoma-like and oligdendroglioma-like, pilocytic astrocytoma-like and epithelioid-like patterns. Immunohistochemically, the tumor cells were positive for GFAP, Olig2 and H3K27M, and H3K27me3 expression was variably lost. ATRX expression was lost in four cases, p53 was strongly positive in 11 cases. Ki-67 index was about 5%-70%. Molecular genetics showed p. k27m mutation in exon 1 of H3F3A gene in 20 cases; BRAF mutation in two cases: V600E and L597Q mutation in one case each. Follow up intervals ranged from 1 to 58 months, and the survival time for brainstem (6.0 months) and non-brainstem (30.4 months) tumors was significantly different (P<0.05). Conclusions: DMG with H3K27 alteration is uncommonly found in adults, mostly occurs in non-brainstem, and can present in adults of all ages. Owing to the wide histomorphologic features, mainly astrocytic differentiation, routine detection of H3K27me3 in midline glioma is recommended. Molecular testing should be performed on any suspected cases to avoid missed diagnosis. Concomitant BRAF L597Q mutation and PPM1D mutation are novel findings. The overall prognosis of this tumor is poor, with tumors located in the brainstem showing worse outcome.

Programmed Intermittent Epidural Bolus in Comparison with Continuous Epidural Infusion for the Effects of Enhanced Recovery after Cesarean Section / 中山大学学报(医学科学版)

ObjectiveTo compare the effects of programmed intermittent epidural bolus （PIEB） and continuous epidural infusion （CEI） on enhanced recovery after cesarean section. MethodsTotally 120 women scheduled to undergo elective cesarean section under combined spinal and epidural anesthesia， aged 18-45 years， with single fetus， full-term pregnancy （≥37 weeks）， ASA grade II or III， were recruited， with 60 cases in each group. At the end of the surgery， after a similar epidural loading dose， patients were randomLy assigned to receive either PIEB （6 mL·h-1 beginning 30 minutes after the loading dose） or CEI （6 mL·h-1， beginning immediately after the loading dose） for the maintenance of analgesia with 0.1% ropivacaine. At 2， 6， 12， 24 and 36 h postoperatively， VAS score was used to evaluate the composite pain， and Bromage Score was used to evaluate the degree of lower extremity motor block. The time to first flatus， time to first ambulation and the satisfaction scores were also recorded. ResultsThe VAS scores at 12， 24 and 36 h postoperatively and the lower extremity motor block scores at 6， 12 and 24 h postoperatively in the PIEB group were significantly lower than those in the CEI group （P < 0.01）. The epidural analgesic dosage was less in the PIEB group than that of the CEI group （P=0.002）. The time to first flatus and time to first ambulation were significantly shorter than those in the CEI group （P < 0.05）. The satisfaction scores were significantly higher in the PIEB group than in the CEI group （P < 0.05）. There was no significant difference in the first urination time after urinary catheter removal and the length of hospital stay between the two groups （P > 0.05）. ConclusionCompared with CEI， PIEB provides better postoperative analgesia， less motor block scores， lower epidural analgesic dosage， shorter the time to first flatus and defecation and time to first ambulation， and greater patient satisfaction， which is more consistent with the ERAS concept of analgesia.

Potassium Acetate-Catalyzed Double Decarboxylative Transannulation To Access Highly Functionalized Pyrroles.

The development of new synthetic strategies for the efficient construction of versatile pyrrole pharmacores, especially in an operationally simple and environmentally benign fashion, still remains a momentous yet challenging goal. Here, we report a KOAc-catalyzed double decarboxylative transannulation between readily accessible oxazolones and isoxazolidinediones. This transformation represents a new way for skeletal remodeling by utilizing CO2 moiety as traceless activating and directing groups in both reaction partners. The synthetic value is evidenced by the rapid preparation of a broad spectrum of highly functionalized 3-carbamoyl-4-aryl pyrroles in good to excellent yields with exclusive regio-control, including the important Atorvastatin core.

Grinding enhances the magnetic hardness of heterometallic diruthenium(ii,iii) carbonates with a kagome lattice structure.

The assembly of paddle-wheel Ru2 building units affords a new trimetallic carbonate, Cs3Cd(H2O)6[{Cd(H2O)3}2{Ru2(CO3)4}3]·10H2O (1), that contains structurally near-perfect kagome layers, {Ru2(CO3)4}n3n-, linked by octahedral Cd(H2O)32+ into a nanoscale kagome network exhibiting ferromagnetic ordering below 3.5 K. The investigation of influences of the grinding method on the crystal samples of compound 1 reveals that the coercivity increases from ∼2.5 Oe to 44.0 Oe upon a grinding treatment for 180 minutes. The results demonstrate that compound 1 can vary from a soft magnet to a hard magnet simply by manually grinding the crystal samples to the nanoscale.

Enhancing magnetic hardness by sonication assisted synthesis of heterometallic carbonato spin-glass Na[Ni(H2O)4Ru2(CO3)4]·3H2O.

Control of magnetic performances of molecular magnets is essential but few efforts have been documented. A green and efficient sonication assisted synthesis of a new heterometallic diruthenium(ii,iii) carbonate, Na[Ni(H2O)4Ru2(CO3)4]·3H2O (1), was carried out by self-assembling in aqueous solution. Compound 1 exhibits spin-glass behavior below ∼5.0 K, and a systematic investigation of the ultrasonic irradiation influence on the powder samples reveals that their coercivity increases from 50 Oe to 743 Oe with the control of ultrasonic power under appropriate conditions.

Alkali counterions tune diruthenium(iii,iii)-based ferrimagnetic chain structured antiferromagnets exhibiting step-like hysteresis loops.

The synthesis of antiferromagnets (AFMs) has attracted extensive attention in the area of magnetic devices, such as spintronics and memory devices. Following our initial work on the employment of the homo-valent diruthenium(iii,iii) paddle wheel species with high spin states (S = 2) as building blocks and active components for the construction of molecule-based magnetic materials, the reaction of mixed-valent diruthenium(ii,iii) phosphates Ru2(H2PO4)2(H1.5PO4)2(H2O)2·2H2O (1) with H2O2, Cu2+ and ACl (A = K, Rb and Cs) in aqueous solution led to the formation of heterometallic copper diruthenium(iii,iii) phosphates A2[Cu(H2O)4Ru2(HPO4)2(PO4)2(H2O)2]·nH2O [A = K (2); A = Rb and n = 2 (3); A = Cs and n = 3 (4)]. The compounds consist of chain structures in which each octahedral environment of Cu(H2O)42+ bonds to two [Ru(HPO4)2(PO4)2]2- units in a trans manner, forming a ferrimagnetic negative chain {Cu(H2O)4Ru2(HPO4)2(PO4)2(H2O)2}n2n-, exhibiting anomalous magnetic properties. Long-range ordering temperatures, Tc, were observed around 10 K, and the control of the chain structured antiferromagnets exhibiting step-like hysteresis loops was successfully achieved through counterion tuning by replacing K with either Rb or Cs.