Electrochemically Driven Deoxygenative Borylation of Alcohols and Carbonyl Compounds.

We present a new, unified approach for the transformation of benzylic and allylic alcohols, aldehydes, and ketones into boronic esters under electroreductive conditions. Key to our strategy is the use of readily available pinacolborane, which serves both as an activator and an electrophile by first generating a redox-active trialkylborate species and then delivering the desired deoxygenatively borylated product. This strategy is applicable to a variety of substrates and can be employed for the late-stage functionalization of complex molecules.

Titanium Radical Redox Catalysis: Recent Innovations in Catalysts, Reactions, and Modes of Activation.

Radical chemistry has emerged as a cornerstone in modern organic synthesis, providing chemists with numerous new tools to rapidly expand reactivity and chemical space in academic and industrial research. In this regard, titanium complexes have been recognized as an attractive class of catalysts owing to their rich redox activities in addition to the abundance and low toxicity of this early transition metal. Traditionally employed for the activation of epoxides and carbonyl compounds, Ti radical redox catalysis has broken into new grounds in recent years, giving rise to a diverse repertoire of useful transformations. In this Perspective, we highlight recent developments in the area of TiIII/IV catalysis with respect to the activation of different types of chemical bonds. Furthermore, we discuss future opportunities in integrating Ti radical chemistry with other catalytic systems as well as with emerging new technologies such as photochemistry and electrochemistry.

Enantioselective Synthesis of N-Alkylamines through ß-Amino C-H Functionalization Promoted by Cooperative Actions of B(C6F5)3 and a Chiral Lewis Acid Co-Catalyst.

We disclose a catalytic method for ß-C(sp3)-H functionalization of N-alkylamines for the synthesis of enantiomerically enriched ß-substituted amines, entities prevalent in pharmaceutical compounds and used to generate different families of chiral catalysts. We demonstrate that a catalyst system comprising of seemingly competitive Lewis acids, B(C6F5)3, and a chiral Mg- or Sc-based complex, promotes the highly enantioselective union of N-alkylamines and α,ß-unsaturated compounds. An array of δ-amino carbonyl compounds was synthesized under redox-neutral conditions by enantioselective reaction of a N-alkylamine-derived enamine and an electrophile activated by the chiral Lewis acid co-catalyst. The utility of the approach is highlighted by late-stage ß-C-H functionalization of bioactive amines. Investigations in regard to the mechanistic nuances of the catalytic processes are described.

B(C6F5)3-Catalyzed α-Deuteration of Bioactive Carbonyl Compounds with D2O.

An efficient deuteration process of α-C-H bonds in various carbonyl-based pharmaceutical compounds has been developed. Catalytic reactions are initiated by the action of Lewis acidic B(C6F5)3 and D2O, converting a drug molecule into the corresponding boron-enolate. Ensuing deuteration of the enolate by in situ-generated D2O+-H then results in the formation of α-deuterated bioactive carbonyl compounds with up to >98% deuterium incorporation.

Catalytic Deuterium Incorporation within Metabolically Stable ß-Amino C-H Bonds of Drug Molecules.

An efficient deuteration process of ß-amino C-H bonds in various N-alkylamine-based pharmaceutical compounds has been developed. Catalytic reactions begin with the action of Lewis acidic B(C6F5)3 and Brønsted basic N-alkylamine, converting a drug molecule into the corresponding enamine. The acid/base catalysts also promote the dedeuteration of acetone-d6 to afford a deuterated ammonium ion. Ensuing deuteration of the enamine then leads to the formation of ß-deuterated bioactive amines with up to 99% deuterium incorporation.

Correction to: Three-dimensional soft tissue changes according to skeletal changes after mandibular setback surgery by using cone-beam computed tomography and a structured light scanner.

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Three-dimensional soft tissue changes according to skeletal changes after mandibular setback surgery by using cone-beam computed tomography and a structured light scanner.

BACKGROUND: To evaluate the three-dimensional (3D) changes after mandibular setback surgery (MSS) in skeletal Class III malocclusion using cone-beam computed tomography (CBCT) and a structured light-based scanner. METHODS: Twenty-eight adult Korean patients with skeletal Class III malocclusion treated by MSS were evaluated. CBCT and facial scan images were recorded one week before and six months after surgery. To use an identical 3D coordinate system, superimposition was performed, and nine skeletal and 18 soft tissue landmarks were identified. Changes in the landmarks and correlation coefficients and ratios between hard and soft tissue changes were evaluated. Paired t test and Pearson's correlation test were performed. RESULTS: After MSS, the amount of transverse correction was 2.45 mm; mandibular setback, 5.80 mm; and vertical reduction, 1.64 mm at the menton, on average. In the transverse axis, there were significant changes and correlations in the lips and chin and an increasing gradient of ratios from the lower lip to the chin. In the anteroposterior axis, the lower lip and chin moved backward significantly and showed notable correlation with hard tissue movement. In the vertical axis, significant upward movement was observed in the landmarks related to the chin, but only lower facial height was significantly decreased. CONCLUSIONS: Soft tissue changes according to hard tissue movement after MSS exhibited a distinct pattern of an increasing gradient from the lips to the chin in a transverse aspect.

An OMICS-based study of the role of C3dg in keratinocytes: RNA sequencing, antibody-chip array, and bioinformatics approaches.

Previously, we have identified the C3dg protein as an important player in the pathogenesis of atopic dermatitis (AD). In this study, we aimed to identify critical factors associated with C3dg in human keratinocytes based on high-throughput screening (HTS) approaches. We overexpressed C3dg in HaCaT human keratinocytes and conducted serial HTS studies, including RNA sequencing analysis integrated with antibody-chip arrays and implementation of bioinformatics algorithms (PPI mappings). Cumulatively, these approaches identified several novel C3dg-associated genes and proteins that are thought to be significantly involved in skin diseases including AD. These novel genes and proteins included LPA, PROZ, BLK, CLDN11, and FGF22, which are believed to play important roles in C3dg-associated skin functions in keratinocytes, as well as genes related to the two important pathways of systemic lupus erythematosus and Staphylococcus aureus infection. In particular, FGF22 is a unique gene that was detected and validated in all methods applied in this study. By integrating the datasets obtained from these HTS studies and utilizing the strengths of each method, we obtained new insights into the functional role of C3dg in keratinocytes. The approach used here contributes to clinical understanding of C3dg-associated applications and may also be applicable to treatment of AD.

B(C6F5)3-Catalyzed C-H Alkylation of N-Alkylamines Using Silicon Enolates without External Oxidant.

An efficient method for the coupling of N-alkylamines with silicon enolates to generate ß-amino carbonyl compounds is disclosed. These reactions proceed by activation of α-amino C-H bonds by B(C6F5)3, which likely generates a "frustrated" acid/base complex in the presence of large N-alkylamines. The transformation requires no external oxidant and releases hydrosilane as a byproduct. The utility of this method is demonstrated in the late-stage functionalization of bioactive molecules such as citalopram, atomoxetine, and fluoxetine.

C-H Functionalization of Amines via Alkene-Derived Nucleophiles through Cooperative Action of Chiral and Achiral Lewis Acid Catalysts: Applications in Enantioselective Synthesis.

Catalytic transformations of α-amino C-H bonds to afford valuable enantiomerically enriched α-substituted amines, entities that are prevalent in pharmaceuticals and bioactive natural products, have been developed. Typically, such processes are carried out under oxidative conditions and require precious metal-based catalysts. Here, we disclose a strategy for an enantioselective union of N-alkylamines and α,ß-unsaturated compounds, performed under redox-neutral conditions, and promoted through concerted action of seemingly competitive Lewis acids, B(C6F5)3, and a chiral Mg-PyBOX complex. Thus, a wide variety of ß-amino carbonyl compounds may be synthesized, with complete atom economy, through stereoselective reaction of an in situ-generated enantiomerically enriched Mg-enolate and an appropriate electrophile.

Measurement of three-dimensional perioral soft tissue changes in dentoalveolar protrusion patients after orthodontic treatment using a structured light scanner.

OBJECTIVE: To evaluate the three-dimensional (3D) perioral soft tissue changes after orthodontic treatment in patients with dentoalveolar protrusion using structured light-based scanners. MATERIALS AND METHODS: Forty-four Korean adults (19 men and 25 women, 21.4 ± 3.4 years) with dentoalveolar protrusion treated by extraction of all four first premolars and then en masse retraction with maximum anchorage were evaluated. Lateral cephalograms and 3D facial scans were obtained before treatment (T1) and immediately after debonding (T2). Superimposition was performed, and 27 perioral landmarks were identified. The 3D changes in the landmarks and ratio of movement of the soft tissue relative to the horizontal incisal tip were evaluated. A paired t-test and one-way analysis of variance were performed. RESULTS: The upper incisors were retracted 5.76 mm and the lower incisors were retracted 4.62 mm (P < .001). The upper lip moved inferoposteriorly, and the lower lip moved superoposteriorly. In the lower lip, upward movement was greater than backward movement (P < .001). The most prominent changes appeared at the greatest bulge area. The relative ratios were 42%-53% in the upper lip area and 22%-82% in the lower lip area. The lip corners moved superoposteriorly (P < .001). Subnasale moved downward (P < .05) and posteriorly (P < .001), while the landmarks under the nostrils moved upward and posteriorly (P < .001). CONCLUSION: Facial scans from white structured light scanners efficiently evaluated 3D perioral soft tissue in dentoalveolar protrusion patients. Backward movement and significant vertical movement of the lip were observed. The nasal and lip angle areas showed considerable changes.