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1.
Org Lett ; 26(15): 2955-2959, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38567894

ABSTRACT

An Eosin Y-catalyzed visible light-promoted 1,4-peroxidation-sulfonylation of enynones was achieved to give tetrasubstituted allenes. The photoredox catalysis of Eosin Y allowed the concomitant formation of peroxy and sulfonyl radicals, where the preferential peroxy radical addition to the alkene moiety of enynones resulted in the subsequent α-keto radical-sulfonyl radical cross couplings. The developed photoredox catalysis of Eosin Y demonstrates a regioselective 1,4-diradical addition strategy, opening up a new possibility of diradical functionalization of conjugate systems.

2.
Org Lett ; 26(18): 4008-4012, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38683186

ABSTRACT

The facile electron transfer catalysis of diaryl diselenides was utilized for the visible-light [4+2] homodimerization of decomposition-prone styrenes. The reaction required only 0.5 mol % TPT+BF4- photocatalyst and 1.5 mol % electron transfer catalyst (ArSe)2. The spontaneous electron transfer capability of diaryl diselenides was demonstrated for the first time, leading to the sequestration of redox-prone radical cation intermediates via electron transfer processes. A variety of polymerization-prone styrenes smoothly underwent the visible-light-promoted [4+2] homodimerization to tetralin derivatives.

3.
J Orthop Sci ; 29(2): 695-702, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37558597

ABSTRACT

Calcium pyrophosphate dihydrate (CPPD) deposition disease is an inflammatory arthritis induced by calcium pyrophosphate (CPP) crystals and clinically it is called pseudogout. It usually deposits in articular cartilage and in periarticular soft tissues. But no cases of pseudogout in the rotator cuff without cartilage deposition or destruction have been reported so far. We present a case of a 57-year-old woman who was diagnosed as pseudogout with rotator cuff tear.


Subject(s)
Cartilage, Articular , Chondrocalcinosis , Rotator Cuff Injuries , Female , Humans , Middle Aged , Chondrocalcinosis/diagnostic imaging , Calcium Pyrophosphate , Rotator Cuff Injuries/diagnostic imaging , Rotator Cuff Injuries/surgery
4.
Orthop J Sports Med ; 11(10): 23259671231205240, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37900867

ABSTRACT

Background: The biomechanical properties of the 1.2-mm suture tape have outperformed conventional sutures in previous studies. Purpose: To compare the loop and knot security of 2 tape-type and 1 cord-type sutures using different arthroscopic knot techniques. Study Design: Controlled laboratory study. Methods: The biomechanical characteristics of the 1.2-mm tape, 2.0-mm tape, and 0.5-mm No. 2 suture were compared using 4 different knot types: 2 sliding knots (Samsung Medical Center [SMC] and Tennessee) and 2 nonsliding knots (2-throw surgeon's and 2-throw square) with 2 and 3 additional reverse half-hitches on alternating posts (RHAPs) in a closed-loop system on a materials testing device. Each configuration was tested for loop security (maximal load applied between 0 and 3 mm of displacement), knot security (ultimate failure load), and failure mode with cyclical loading (30 N load for 20 cycles at 1 cycle per sec until failure). Loop and knot security among the configurations were compared using an analysis of variance. Results: With 2 RHAPs, the 2.0-mm tape showed significantly greater loop security than the 1.2-mm tape and suture (P = .001). With 3 RHAPs, the loop security of the suture was significantly superior compared with the 1.2-mm tape (P = .010). Regarding knot security, with 2 RHAPs, the 2.0-mm tape was significantly better than the 1.2-mm tape and suture (P < .001), while with 3 RHAPs, the suture was significantly superior to the 1.2-mm tape (P = .012). Using a square knot with 2 RHAPs, the 2.0-mm tape had significantly greater loop security (P = .001) and better knot security (P = .001) to the 1.2-mm tape and suture. Using the Tennessee knot with 2 RHAPs, the 1.2-mm tape had less loop security (P = .011) and knot security (P = .005) than the suture. Using the SMC knot with 3 RHAPs, the 2.0-mm tape and suture were significantly superior in loop security (P = .001) and knot security (P < .001) to the 1.2-mm tape. There was no significant difference in the failure mode between tapes and sutures with 2 and 3 RHAPs. Conclusion: With 2 RHAPs, the 2.0-mm tape demonstrated greater resistance to suture loop displacement and better knot security compared with the 1.2-mm tape and suture. However, with 3 RHAPs, the 1.2-mm tape manifested weaker loop and knot security compared with the suture.

5.
Org Lett ; 25(39): 7204-7208, 2023 Oct 06.
Article in English | MEDLINE | ID: mdl-37737122

ABSTRACT

The visible light excitation of areneazo-2-(2-nitro)propane·HCl salts generated the singlet aryl cation that readily underwent aromatic SN1 reactions with a variety of nucleophiles. The in situ generated singlet aryl cation was stabilized by a counter nitronate anion that prevented other intersystem crossing and single electron transfer processes. With the improved safety features of neutral areneazo-2-(2-nitro)propane derivatives, the current visible-light-promoted aromatic SN1 reactions provide an alternative aryl Csp2-X bond forming strategy.

6.
Knee Surg Sports Traumatol Arthrosc ; 31(11): 5238-5247, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37594502

ABSTRACT

PURPOSE: Joint stiffness after arthroscopic rotator cuff repair is a major concern for orthopaedic surgeons. Various antiadhesive agents are commonly administered after rotator cuff repair for its prevention. This study aimed to compare the outcomes among patients injected with different types and amounts of anti-adhesive agents after rotator cuff repair. It was hypothesized that the outcomes might differ depending on the use of the anti-adhesive agent and its type and dose. METHODS: A total of 267 patients who underwent arthroscopic rotator cuff repair with or without subacromial injection of anti-adhesive agents were enrolled. The first group (group A; 51 patients) were injected with 3 mL of poloxamer/sodium alginate-based anti-adhesive agent. The second group (group B; 93 patients) were injected with 3 mL of sodium hyaluronate-based anti-adhesive agent. The third group (group C; 82 patients) were injected with 1.5 mL of sodium hyaluronate-based anti-adhesive agent. Finally, the last group (group D; 41 patients) who did not use anti-adhesive agents served as the control. The range of motion (ROM) and pain VAS scores were measured preoperatively and at 5 weeks, 3 months, 6 months, and 1 year postoperatively. Functional outcomes were evaluated using American Shoulder and Elbow Surgeons and Constant scores, whereas cuff integrity was assessed via MRI or ultrasonography at least 6 months postoperatively. RESULTS: All ROM measurements, pain VAS scores, and functional scores were significantly improved regardless of the use, type, and dose of the anti-adhesive agents. In addition shoulder ROM and rotator cuff healing did not significantly differ among the groups (all n.s.). CONCLUSIONS: No significant differences were found in the clinical and anatomical outcomes according to the type and dose of the anti-adhesive agents subacromially injected after rotator cuff repair. LEVEL OF EVIDENCE: III.

7.
Org Lett ; 25(30): 5697-5701, 2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37494288

ABSTRACT

Different addition modes of sulfinic acids were developed for the chemodivergent sulfonylation of enynones, where the ionic sulfonylation to an alkyne moiety of enynones was effected through a salt-controlled syn-addition pathway. The radical sulfonylation of an alkene moiety also provided the stereodefined sulfonylated alkenes. A one-pot tandem sequence of the Ti(Oi-Pr)4-catalyzed α-vinyl aldol condensation of (E)-ß-chlorovinyl ketones followed by the chemodivergent sulfonylations was also explored, allowing for ready access to highly substituted dienes and enynes.

8.
ACS Infect Dis ; 9(8): 1582-1592, 2023 08 11.
Article in English | MEDLINE | ID: mdl-37415514

ABSTRACT

The HIV-1 infection epidemic remains a global health problem. Current antiretroviral treatments are effective in controlling the progression of a severe infection. However, the emergence of drug resistance requires an urgent identification of new treatment regimes. HIV-1 reverse transcriptase (RTs) has been a successful therapeutic target owing to its high specificity and potent antiviral properties; therefore, it has become an essential component of current HIV-1 standard treatments. This study identified a new HIV-1 RTs inhibitor (Compound #8) that is structurally unique and greatly effective against HIV-1 through chemical library screening and a medicinal chemistry program by analyzing the structure-activity relationship (SAR). Further analysis of molecular docking and mechanisms of action demonstrated that Compound #8 is a novel type of HIV-1 non-nucleoside reverse transcriptase inhibitor (NNRTI) with a flexible binding mode. Therefore, it exhibits great therapeutic potential when combined with other existing HIV-1 drugs. Our current studies suggest that Compound #8 is a promising novel scaffold for the development of new HIV-1 treatments.


Subject(s)
HIV Infections , HIV-1 , Humans , Reverse Transcriptase Inhibitors/pharmacology , Reverse Transcriptase Inhibitors/therapeutic use , Reverse Transcriptase Inhibitors/chemistry , Molecular Docking Simulation , Antiviral Agents/pharmacology , HIV Infections/drug therapy
9.
PLoS One ; 18(5): e0284111, 2023.
Article in English | MEDLINE | ID: mdl-37200275

ABSTRACT

INTRODUCTION: Rotator cuff tear (RCT) is a challenging and common musculoskeletal disease. Magnetic resonance imaging (MRI) is a commonly used diagnostic modality for RCT, but the interpretation of the results is tedious and has some reliability issues. In this study, we aimed to evaluate the accuracy and efficacy of the 3-dimensional (3D) MRI segmentation for RCT using a deep learning algorithm. METHODS: A 3D U-Net convolutional neural network (CNN) was developed to detect, segment, and visualize RCT lesions in 3D, using MRI data from 303 patients with RCTs. The RCT lesions were labeled by two shoulder specialists in the entire MR image using in-house developed software. The MRI-based 3D U-Net CNN was trained after the augmentation of a training dataset and tested using randomly selected test data (training: validation: test data ratio was 6:2:2). The segmented RCT lesion was visualized in a three-dimensional reconstructed image, and the performance of the 3D U-Net CNN was evaluated using the Dice coefficient, sensitivity, specificity, precision, F1-score, and Youden index. RESULTS: A deep learning algorithm using a 3D U-Net CNN successfully detected, segmented, and visualized the area of RCT in 3D. The model's performance reached a 94.3% of Dice coefficient score, 97.1% of sensitivity, 95.0% of specificity, 84.9% of precision, 90.5% of F1-score, and Youden index of 91.8%. CONCLUSION: The proposed model for 3D segmentation of RCT lesions using MRI data showed overall high accuracy and successful 3D visualization. Further studies are necessary to determine the feasibility of its clinical application and whether its use could improve care and outcomes.


Subject(s)
Deep Learning , Rotator Cuff Injuries , Humans , Imaging, Three-Dimensional/methods , Rotator Cuff Injuries/diagnostic imaging , Image Processing, Computer-Assisted/methods , Algorithms , Magnetic Resonance Imaging/methods
10.
Knee Surg Sports Traumatol Arthrosc ; 31(8): 3541-3558, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37038019

ABSTRACT

PURPOSE: This study aimed to compare the clinical results of revision Bankart repair versus the Latarjet procedure for failed Bankart repair. METHODS: A literature search was performed in databases, such as Pubmed, Embase, and Scopus Library. The studies were appraised using the Methodological Index for Non-randomized Studies tool. Studies for failed Bankart repair with revision Bankart repair or Latarjet procedure were included. The pain VAS, ROWE score, rate of return to sports and preinjury level of sports, recurrent instability, range of motion, and complications were compared. Additionally, the pain VAS, ROWE score, forward flexion, and external rotation at side were subjected to a meta-analysis. RESULTS: Twenty-four articles were included in the systematic review. The functional outcomes in terms of the ROWE score, recurrent instability, return to sports, and the preinjury level of sports was better in the Latarjet procedure group than those in the revision Bankart repair group (ROWE score, 91 vs. 86.7; recurrent instability rate, 3.5% vs. 14.4%; return to sports rate, 100% vs. 87.9%; return to preinjury level of sports rate, 89.9% vs. 74.9%; all P < 0.001). However, the results of postoperative pain and the postoperative limitation of external rotation at side were worse in the Latarjet procedure group than those in the revision Bankart repair group (pain VAS, 1.4 vs. 0.8; postoperative external rotation at side, 38° vs. 60°; all P < 0.001). In addition, the majority of the complications occurred in the Latarjet procedure group. In the meta-analysis, the postoperative ROWE score was significantly higher in the Latarjet procedure group than that in the revision Bankart group (revision Bankart repair: 95% CI 88.9-80.9, I2 = 65.70; Latarjet procedure: 95% CI 95.8-88.1, I2 = 93.37; P = 0.014). However, the pain VAS, forward flexion, and external rotation at side did not reach the significant level in the meta-analysis. CONCLUSION: Compared with revision Bankart repair, the Latarjet procedure for failed Bankart repair showed better ROWE scores, stability, and return to sports or preinjury level of sports; however, the postoperative pain and the limitation of external rotation at side were worse with more complications. IRB NO: KUMC 2022-01-024. LEVEL OF EVIDENCE: Level IV.


Subject(s)
Joint Instability , Shoulder Dislocation , Shoulder Joint , Humans , Shoulder Dislocation/surgery , Shoulder Joint/surgery , Return to Sport , Arthroscopy/methods , Recurrence , Pain , Retrospective Studies
11.
Org Lett ; 25(2): 449-453, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36626165

ABSTRACT

Secondary nitroalkanes underwent oxygen-mediated nitro-nitrite isomerization, serving as versatile N-nitrosating agents under aerobic conditions. To capitalize on the newly discovered aerobic nitro-nitrite isomerization phenomenon, a phase-transfer catalysis system employing KSeCN and TBAI was developed, in which the tandem diazotization and azo coupling with nitroalkanes as well as N-nitrosation of amines were accomplished. The current tandem diazotization and azo coupling strategy provides a facile synthesis of areneazo-2-(2-nitro)propane derivatives, a safe synthetic alternative to aryl diazonium salts.

12.
Clin Shoulder Elb ; 26(3): 302-305, 2023 Sep.
Article in English | MEDLINE | ID: mdl-35545243

ABSTRACT

The authors present a case of transient postoperative inferior subluxation of the shoulder after arthroscopic surgical stabilization for recurrent anterior dislocation. The patient was a 61-year-old woman with myasthenia gravis (MG). The first anterior shoulder dislocation occurred because of a fall to the ground. Despite a successful closed reduction, two more dislocations occurred in 3 weeks. Magnetic resonance imaging revealed an anterior labroligamentous periosteal sleeve avulsion (ALPSA) lesion, an engaging Hill-Sachs lesion, and large tears of the supraspinatus and infraspinatus tendons. The patient underwent arthroscopic rotator cuff repair and ALPSA repair with a remplissage procedure. Intraoperatively, no tendency for instability was found; however, a widened glenohumeral joint space and inferior subluxation of the humeral head without functional compromise was observed on the day after surgery and disappeared spontaneously on radiographs 2 weeks later. To the authors' knowledge, this is the first report documenting the occurrence of transient postoperative inferior subluxation of the shoulder in a patient with MG.

13.
Org Lett ; 25(1): 288-292, 2023 01 13.
Article in English | MEDLINE | ID: mdl-36580377

ABSTRACT

A one-pot tandem approach to [1,2,3]triazolo[1,5-a]quinolines was developed from (E)-ß-chlorovinyl ketones and 2-azidoaryl carbonyls using a sequence of α-vinyl aldol and azide-alkyne cycloaddition reactions. In particular, the intramolecular azide-alkyne cycloaddition of allenol intermediates was readily promoted by a synergistic action of NEt3 and nickel catalysts. Given that the [1,2,3]triazolo[1,5-a]quinolines are useful synthetic precursors to α-diazoimines through ring-chain isomerization process, the subsequent denitrogenative transformations should provide ready access to valuable heterocyclic compounds.


Subject(s)
Nickel , Quinolines , Azides , Cycloaddition Reaction , Molecular Structure , Cyclization , Alkynes , Catalysis
14.
Org Lett ; 24(46): 8531-8535, 2022 Nov 25.
Article in English | MEDLINE | ID: mdl-36354741

ABSTRACT

The catalytic diazotization of aryl amines was developed using ortho-naphthoquinone catalyst under aerobic conditions, where the 2-nitropropane served as a source of nitrosonium ion. The catalytic generation of diazonium species from aryl amines was further explored in the hydrode-diazotization to give the corresponding products. The mechanistic studies indicated the involvement of aryl radical species that readily underwent the radical cyclization to alkenes as well as the halogen abstraction reactions.

15.
Org Lett ; 24(46): 8465-8469, 2022 Nov 25.
Article in English | MEDLINE | ID: mdl-36367131

ABSTRACT

A photocatalyst-free visible-light-induced selenofunctionalization of alkenes has been developed using a variety of nucleophiles. The homolytic scission of diselenides under visible-light conditions coupled with the aerobic selenol oxidation to diselenides allowed the successful implementation of three-component selenofunctionalization under visible-light irradiation in open-air conditions. The mechanistic studies revealed the critical role of oxygen content in a reaction medium, where the electron transfer process from the carbon-based radicals to either molecular oxygen or selenyl radicals was controlled.

16.
Org Lett ; 24(31): 5840-5844, 2022 Aug 12.
Article in English | MEDLINE | ID: mdl-35921551

ABSTRACT

The photoaddition of N-nitrosopiperidines to terminal alkynes was effected under visible-light irradiation, in which a novel synthetic access to tetrahydroimidazo[1,2-a]pyridine 1-oxides was achieved via the dehydrogenative cycloisomerization of ß-nitroso enamine intermediates. The decomposition pathways of N-nitrosamines, alkynes, and ß-nitroso enamine intermediates were better handled in a continuous flow setting through the diffusion control of chemical species that negatively affected the formation of tetrahydroimidazo[1,2-a]pyridine 1-oxides under batch reaction conditions.

17.
Org Lett ; 24(27): 4982-4986, 2022 07 15.
Article in English | MEDLINE | ID: mdl-35796666

ABSTRACT

A biomimetic alcohol dehydrogenase (ADH)-like oxidation protocol was developed using an ortho-naphthoquinone catalyst in the presence of a catalytic amount of base. The developed organocatalytic aerobic oxidation protocol proceeds through the intramolecular 1,5-hydrogen atom transfer of naphthalene alkoxide intermediates, a mechanistically distinctive feature from the previous alcohol dehydrogenase mimics that require metals in the active form of catalysts. The ADH-like aerobic oxidation protocol should provide green alternatives to the existing stoichiometric and metal-catalyzed alcohol oxidation reactions.


Subject(s)
Alcohols , Aldehydes , Alcohol Dehydrogenase , Catalysis , Ketones , Metals , Naphthoquinones , Oxidation-Reduction
18.
Org Lett ; 24(29): 5287-5292, 2022 Jul 29.
Article in English | MEDLINE | ID: mdl-35848887

ABSTRACT

A continuous flow system to 1,4-benzothiazines was developed using the point of reaction control, where the ambivalent (E)-ß-chlorovinyl ketones and 2,2'-dithiodianilines were confined in a diffusion controlled flow setting. The successful segregation of reactive chemical species in a flow setting allowed more defined reaction pathways that are not feasible in traditional batch reaction conditions. The point of reaction control in flow systems helps to execute the reactions often plagued with the concurrent generation of multiple chemical species.

19.
Org Lett ; 24(14): 2636-2640, 2022 04 15.
Article in English | MEDLINE | ID: mdl-35385289

ABSTRACT

A traceless arylsulfinate mediator strategy has been developed to switch the reaction course of ß-chlorovinyl ketones with N-hydroxyamine. The soft α-vinyl enolization of (E)-ß-chlorovinyl ketones was conducted in the presence of sodium arylsulfinate to give transient alkenyl sulfones that in turn reacted with NH2OH to give novel access to N-hydroxypyrroles. The mechanistic studies revealed the initial formation of oxazine intermediates that rearranged to thermodynamically stable aromatic products, N-hydroxypyrroles, under microwave-assisted heating conditions.


Subject(s)
Ketones
20.
Org Lett ; 24(9): 1812-1816, 2022 03 11.
Article in English | MEDLINE | ID: mdl-35200032

ABSTRACT

A catalytic asymmetric desymmetrization of cyclohexadienones was accomplished via Van Leusen pyrrole synthesis in the presence of a chiral silver catalyst. The ready access to chiral-fused pyrrole derivatives is attributed to the identification of a suitable isocyanomethyl sulfone surrogate, NasMIC. The current Ag(I)-chiral phosphino-carboamide ligand system can be extended to the kinetic resolution of racemic cyclohexadienones, capitalizing on the differentiated reactivity of chiral quaternary complexes from AgSbF6, chiral ligand (L*), cyclohexadienone, and NasMIC.


Subject(s)
Pyrroles , Silver , Catalysis , Cyclohexenes , Ligands , Stereoisomerism
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