Programmable synthesis of difluorinated hydrocarbons from alkenes through a photocatalytic linchpin strategy.

The introduction of difluoromethylene moieties into organic molecules has garnered significant attention due to their profound influence on the physicochemical and biological properties of compounds. Nonetheless, the existing approaches for accessing difluoroalkanes from readily available feedstock chemicals remain limited. In this study, we present an efficient and modular protocol for the synthesis of difluorinated compounds from alkenes, employing the readily accessible reagent, ClCFSONa, as a versatile "difluoromethylene" linchpin.

[Value of complement component 3 in predicting the prognosis of children with sepsis].

Objectives: To investigate changes in complement component 3 (C3) levels in children with sepsis and its correlation with the severity of sepsis and to explore the significance of C3 in predicting mortality in children with sepsis.

Methods: A retrospective analysis was conducted on 529 children with sepsis who were admitted to the Pediatric Intensive Care Unit in Hunan Children's Hospital between November 2019 and September 2021. The children were categorized into two groups based on their prognosis at day 28 after sepsis diagnosis: the survival group (=471) and the death group (=58).

Photoinduced Defluorinative Branch-Selective Olefination of Multifluoro (Hetero)arenes.

We report a photoredox platform for constructing styrenyl polyfluoro (hetero)arenes with branch selectivity by taking advantage of sulfinate as both a radical-relay precursor and a sacrificial nucleofuge. This protocol merges photoredox catalysis with radical-radical coupling and an elimination process in a one-pot operation and features good functional group tolerance, mild conditions, and a facile method to access polyfluoro (hetero)aryl derivatives of natural products and drugs.

Difluoromethylation of Unactivated Alkenes Using Freon-22 through Tertiary Amine-Borane-Triggered Halogen Atom Transfer.

The application of abundant and inexpensive fluorine feedstock sources to synthesize fluorinated compounds is an appealing yet underexplored strategy. Here, we report a photocatalytic radical hydrodifluoromethylation of unactivated alkenes with an inexpensive industrial chemical, chlorodifluoromethane (ClCFH, Freon-22). This protocol is realized by merging tertiary amine-ligated boryl radical-induced halogen atom transfer (XAT) with organophotoredox catalysis under blue light irradiation.

[Using direct enzyme linked immunosorbent assay for the detection of IgG antibody on Bartonella henselae among healthy people in Changping, Beijing].

Objective: To detect Bartonella henselae IgG antibody among healthy people in Changping, Beijing.

Methods: Using indirect enzyme linked immunosorbent assay (ELISA) and immunofluorescence antibody assay (IFA) to detect IgG antibody of Bartonella henselae among human beings.

Results: The sensitivity and specificity of ELISA were 70.

A highly regioselective amination of 6-aryl-2,4-dichloropyrimidine.

[reaction: see text]. A highly regioselective amination of 6-aryl-2,4-dichloropyrimidine with aliphatic secondary amines and aromatic amines has been developed which strongly favors the formation of the C4-substituted product. The reactions with aliphatic amines are carried out using LiHMDS as the base and are catalyzed by Pd, while the aromatic amines require no catalyst.

[3 + 2] Annulation of allylic silanes in acyclic stereocontrol: total synthesis of (9S)-dihydroerythronolide A.

The [3 + 2] annulation reactions of allylic silanes can be utilized to achieve acyclic stereocontrol. This method was employed as a key step in an enantioselective total synthesis of (9S)-dihydroerythronolide A. The key annulation reaction served to establish most of the stereochemistry of the target, including the two tetrasubstituted carbon stereocenters.

Synthesis of (+/-)-5-epi-citreoviral and (+/-)-citreoviral and the kinetic resolution of an allylic silane by a [3 + 2] annulation.

[reaction: see text] The [3 + 2] annulation reaction of allylsilane 1 with an alpha-keto ester provided the highly substituted tetrahydrofuran 2 as a single diastereomer in high yield. The synthesis of (+/-)-5-epi-citreoviral and (+/-)-citreoviral has been accomplished with this annulation reaction as the key step. Using the pantolactone-derived alpha-keto ester, the allylsilane 1 has been resolved with high enantiomeric purity.