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Purpose: Many systemic inflammatory markers have been identified to be prognostic factors in various diseases, including colorectal cancer (CRC). The Colon Inflammatory Index (CII), which is based on the lactate dehydrogenase (LDH) level and the neutrophil-to-lymphocyte ratio (NLR), is reportedly a predictor of the outcome of chemotherapy in patients with metastatic CRC. This retrospective review study aimed to determine whether CII can predict the prognosis after surgical resection of CRC. Methods: A total of 1,273 patients who underwent CRC resection were enrolled and divided into a training cohort (n = 799) and a validation cohort (n = 474). The impact of the preoperative CII score on overall survival (OS) and recurrence-free survival (RFS) was assessed. Results: In the training cohort, the CII score was good in 569 patients (71.2%), intermediate in 209 (26.2%), and poor in 21 (2.6%). There were significant between-group differences in body mass index, American Society of Anaesthesiologists physical status, and preoperative tumour markers. The 5-year OS rate was significantly lower in patients with an intermediate or poor CII score (CII risk) than in those with no CII risk (73.8% vs. 84.2%; p < 0.001, log-rank test). In multivariate analysis, CII risk remained a significant independent predictor of poor OS (hazard ratio 1.75; 95% confidence interval 1.18–2.60; p = 0.006). In the validation cohort, the 5-year OS rate was significantly lower in patients with CII risk than in those with no CII risk (82.8% vs. 88.4%; p = 0.046, log-rank test). Conclusion: These findings indicate that the CII can predict OS after resection of CRC. [ABSTRACT FROM AUTHOR]

Thymic carcinoma, a rare mediastinal neoplasm, is characterized by extensive local invasion and distant metastasis. To our knowledge, this is the first case report demonstrating the efficacy of laparoscopic dissection for pelvic lymph node metastases from thymic carcinoma. A 64‐year‐old man was found to have a mediastinal mass by CT and underwent radical resection. Six months after resection of his thymic carcinoma, follow‐up CT revealed a gluteal tumor and enlarged pelvic lymph nodes. The gluteal tumor was resected percutaneously. Two months after this procedure, PET showed that the three pelvic lymph nodes had abnormal uptake of 18F‐fluorodeoxyglucose and had enlarged further. The patient accordingly underwent laparoscopic dissection of these lymph nodes. Pathological examination of all resected specimens showed metastatic thymic carcinoma. We recommend laparoscopic dissection of pelvic lymph node metastases because it provides a clear intraoperative view and is minimally invasive. [ABSTRACT FROM AUTHOR]

Pelvic infection is a significant clinical problem after pelvic exenteration. The clinical benefit of an omental flap in reducing the incidence of such infections is unknown. The aim of this study was to evaluate whether an omental flap after pelvic exenteration reduces the incidence of pelvic infection and the length of postoperative hospital stay. In this study, we demonstrate a safe, effective, simple method for reducing the incidence of pelvic infection using an omental flap. We performed pelvic exenteration for tumors that were suspected to have extensive invasion to the bladder, prostate, or uterus. The omentum was dissected from the transverse colon and greater curvature of the stomach. The flap was based on the right gastroepiploic vessels and tunneled in the retrocolic plane, through the mesentery of the transverse colon and ileocecum, to the defect. Twenty-seven patients were analyzed retrospectively. Ten patients received omental flaps, and 17 patients underwent pelvic exenteration without an omental flap. The incidence of pelvic infection was significantly reduced in the patients with omental flaps. [ABSTRACT FROM AUTHOR]

A strategy for oxidative kinetic resolution of racemic indolines was developed, employing salicylaldehyde derivative as the pre-resolving reagent and chiral phosphoric acid as the catalyst. The iminium intermediate, formed by the condensation reaction of an enantiomer of indoline with salicylaldehyde derivative, was hydrogenated by the same enantiomer of indoline to afford another enantiomer of indoline by a self-redox mechanism. The oxidative kinetic resolution of 2-aryl-substituted indolines proceeded to give enantiomers in good yields with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

A strategy for oxidative kinetic resolution of racemic indolines was developed, employing salicylaldehyde derivative as the pre-resolving reagent and chiral phosphoric acid as the catalyst. The iminium intermediate, formed by the condensation reaction of an enantiomer of indoline with salicylaldehyde derivative, was hydrogenated by the same enantiomer of indoline to afford another enantiomer of indoline by a self-redox mechanism. The oxidative kinetic resolution of 2-aryl-substituted indolines proceeded to give enantiomers in good yields with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

Described herein are differences in behavior between a Hantzsch ester and a benzothiazoline as hydrogen donors in the chiral phosphoric acid catalyzed asymmetric reductive amination of ketones with p-anisidine. The asymmetric reductive amination of ketones with a Hantzsch ester as a hydrogen donor provided the corresponding chiral amines exclusively, regardless of the structures of the ketones, whereas a similar transformation with a benzothiazoline provided chiral amines and p-methoxyphenyl-protected primary amines in variable yields, depending on the structures of both the ketones and benzothiazolines. Because a benzothiazoline has an N,S-acetal moiety that is vulnerable to p-anisidine, the primary amine can be formed through transimination of the benzothiazoline with p-anisidine followed by reduction of the resulting aldimine with remaining benzothiazoline. [ABSTRACT FROM AUTHOR]

[21][24] We wish to report herein our synthetic approach toward -hydroxyamino ketones, which involves the radical acylation of nitrone with 2-acylbenzothiazolene under organophotoredox catalysis (route C). Metal- and Additive-Free Synthesis of -Hydroxyamino Ketones Enabled by Organophotocatalyst Hydroxyamino ketone, hydroxylamine, nitrone, benzothiazoline, metal-free, organophotocatalyst Keywords: hydroxyamino ketone; hydroxylamine; nitrone; benzothiazoline; organophotocatalyst; metal-free EN hydroxyamino ketone hydroxylamine nitrone benzothiazoline organophotocatalyst metal-free 1391 1394 4 07/11/23 20230725 NES 230725 Graph Nitrogen-containing compounds are prevalent in organic compounds, and a range of novel catalytic approaches have been extensively explored. [Extracted from the article]

The high-yield reduction of aromatic ketimines into amines by using a novel catalyst based on a metallacarborane structure, 8,8'-μ-phosphate[(1,2-dicarba-closo-undecaborane)-3,3'-cobalt(- 1)(1',2'-dicarba-closo-undecaborane)] acid, is described. [ABSTRACT FROM AUTHOR]

Abstract: The enantioselective hydrophosphonylation reaction of diisopropyl phosphite with aldimine furnished α-amino phosphonates with high enantioselectivities by means of a chiral phosphoric acid. DFT calculation of the effect of 3,3′-substituents of the phosphoric acid revealed the reason for the high enantioselectivities. [Copyright &y& Elsevier]

In order to determine the separatrix shapes of field-reversed configuration plasmas with high accuracy, an iterative method that compares measured magnetic fluxes with the solution of the Grad-Shafranov equation is discussed in detail. Several suggestions for successfully treating the iterative method are given using numerical simulation and a mock-up experiment where conductors with three kinds of shape are inserted into the coil instead of the plasma. The iterative method is also applied to the field-reversed configuration plasma, and it is found that the separatrix shape has distinct ends and the axial location of the X point can be determined. [ABSTRACT FROM AUTHOR]

Photoinduced single‐electron reduction is an efficient method for the mono‐selective activation of the C−F bond on a trifluoromethyl group to construct a difluoroalkyl group. We have developed an electron‐donor‐acceptor (EDA) complex mediated single‐electron transfer (EDA‐SET) of α,α,α‐trifluoromethyl arenes in the presence of lithium salt to give α,α‐difluoroalkylarenes. The C−F bond reduction was realized by lithium iodide and triethylamine, two common feedstock reagents. Mechanistic studies revealed the generation of a α,α‐difluoromethyl radical by single‐electron reduction and defluorination, followed by the radical addition to alkenes. Lithium salt interacted with the fluorine atom to promote the photoinduced reduction mediated by the EDA complex. Computational studies indicated that the lithium‐assisted defluorination and the single‐electron reduction occurred concertedly. We call this phenomenon fluoride‐coupled electron transfer (FCET). FCET is a novel approach to C−F bond activation for the synthesis of organofluorine compounds. [ABSTRACT FROM AUTHOR]

Asymmetric catalysis stands at the forefront of modern chemistry, serving as a cornerstone for the efficient creation of enantiopure chiral molecules characterized by their high selectivity. In this review, we delve into the realm of asymmetric catalytic reactions, which spans various methodologies, each contributing to the broader landscape of the enantioselective synthesis of chiral molecules. Transition metals play a central role as catalysts for a wide range of transformations with chiral ligands such as phosphines, N-heterocyclic carbenes (NHCs), etc., facilitating the formation of chiral C-C and C-X bonds, enabling precise control over stereochemistry. Enantioselective photocatalytic reactions leverage the power of light as a driving force for the synthesis of chiral molecules. Asymmetric electrocatalysis has emerged as a sustainable approach, being both atom-efficient and environmentally friendly, while offering a versatile toolkit for enantioselective reductions and oxidations. Biocatalysis relies on nature's most efficient catalysts, i.e., enzymes, to provide exquisite selectivity, as well as a high tolerance for diverse functional groups under mild conditions. Thus, enzymatic optical resolution, kinetic resolution and dynamic kinetic resolution have revolutionized the production of enantiopure compounds. Enantioselective organocatalysis uses metal-free organocatalysts, consisting of modular chiral phosphorus, sulfur and nitrogen components, facilitating remarkably efficient and diverse enantioselective transformations. Additionally, unlocking traditionally unreactive C-H bonds through selective functionalization has expanded the arsenal of catalytic asymmetric synthesis, enabling the efficient and atom-economical construction of enantiopure chiral molecules. Incorporating flow chemistry into asymmetric catalysis has been transformative, as continuous flow systems provide precise control over reaction conditions, enhancing the efficiency and facilitating optimization. Researchers are increasingly adopting hybrid approaches that combine multiple strategies synergistically to tackle complex synthetic challenges. This convergence holds great promise, propelling the field of asymmetric catalysis forward and facilitating the efficient construction of complex molecules in enantiopure form. As these methodologies evolve and complement one another, they push the boundaries of what can be accomplished in catalytic asymmetric synthesis, leading to the discovery of novel, highly selective transformations which may lead to groundbreaking applications across various industries. [ABSTRACT FROM AUTHOR]

Highlights: [•] In this study we examine the hydrodefluorination of trifluorotoluene derivatives. [•] TiCl4 proved to be more active than NbCl5 as a co-catalyst. [•] Selective hydrodefluorination is possible. [Copyright &y& Elsevier]

Abstract: A benzothiazoline bearing 4-carboxyphenyl group at 2-position was developed as an efficient hydrogen donor for the transfer hydrogenation reaction. Introduction of the carboxyl group significantly facilitated the removal of the residual benzothiazoline and benzothiazole by washing with aqueous basic solution. The present approach provides a convenient and straightforward access to various amines with broad substrate scope and in good yields. [Copyright &y& Elsevier]

A variety of indoles underwent enantioselective Friedel–Crafts alkylation with α,β-unsaturated acyl phosphonates in the presence of 10 mol% chiral BINOL-based phosphoric acid and subsequent treatment with methanol and DBU to give methyl 3-(indol-3-yl)propanoates in good yields and with high enantioselectivities. [ABSTRACT FROM AUTHOR]

Abstract: The Brønsted acid-catalyzed Nazarov cyclization of pyrrole derivatives was developed. Microwave irradiation accelerated the Nazarov cyclization significantly at 40°C to give cyclopenta[b]pyrrole derivatives in excellent yields with high trans selectivity. [Copyright &y& Elsevier]

A novel chiral phosphoric acid bearing a biphenol backbone was synthesized and its catalytic activity was investigated in the enantioselective Mannich-type reaction of ketene silyl acetals with aldimines. [ABSTRACT FROM AUTHOR]

A novel chiral phosphoric acid bearing a biphenol backbone was synthesized and its catalytic activity was investigated in the enantioselective Mannich-type reaction of ketene silyl acetals with aldimines. [ABSTRACT FROM AUTHOR]

Treatment of trifluoroacetaldehyde N,O-acetal with diazoacetate in the presence of a Lewis acid furnished CF3-substituted aziridinecarboxylates in good yields. Both cis and trans isomers were obtained stereoselectively by the proper choice of the ester substituents. Use of a chiral diazoacetate derived from (R)-pantolactone led to highly diastereoselective aziridination (94% de). [Copyright &y& Elsevier]

Introduction: The present study assessed the utility of a dry box time trial during laparoscopic surgical training to improve laparoscopic surgical skills and surgical outcomes. Methods: In a monthly time trial, surgeon trainees twice completed a set task that involved grasping a suture, aligning a needle with a needle holder, passing the suture, making three knots, and cutting the two tails of the suture. The mean suturing time was then analyzed. To assess the utility of this time trial, we analyzed the short‐term outcomes of patients with stage I to III colon cancer who had undergone laparoscopic colectomy before and after the introduction of the time trial. Results: The monthly time trial was introduced in October 2018, and 52 surgeon trainees participated in the trials examined in this study. Within 6 months of the program's introduction, the mean suturing time had significantly declined to less than 70% of the time trial, while the standard deviations had declined to less than 30%. In comparisons of the short‐term outcomes of laparoscopic colon cancer surgery before (n = 49) and after (n = 46) the introduction of the time trial, the operative time tended to decline (P =.074) after the introduction of the time trial, and blood loss was significantly reduced (P =.018). The rate of postoperative complications was similar before and after the introduction. Conclusion: Regular time trials of laparoscopic surgical suture training using a dry box can be useful for improving laparoscopic surgical skills and surgical outcomes. Moreover, time trials can keep trainees motivated. [ABSTRACT FROM AUTHOR]

Quinoline and indole are important core structures in biologically active compounds and materials. Atropisomeric biaryls consisting of quinoline and indole are a unique class of axially chiral molecules. We report herein enantioselective synthesis of 3-(N-indolyl)quinolines having both C–N axial chirality and carbon central chirality by a photoredox Minisci-type addition reaction catalyzed by a chiral lithium phosphate/Ir-photoredox complex. The catalytic system enabled access to a unique class of 3-(N-indolyl)quinolines with high chemo-, regio-, and stereoselectivities in good yields through the appropriate choice of an acid catalyst and a photocatalyst. This is the first example of the synthesis of 3-(N-indolyl)quinoline atropisomers in a highly enantioselective manner. [ABSTRACT FROM AUTHOR]

Purpose: Advanced esophageal cancer often results in esophageal stenosis or tracheoesophageal fistula. Esophageal bypass surgery and esophageal stent insertion are palliative treatments for esophageal cancer. With improvements in metallic stents and the stent insertion technique, esophageal stent insertion appears to be performed more frequently than bypass surgery, worldwide. The aim of this study was to evaluate the outcomes of bypass surgery and stent insertion in our hospital and reevaluate which patients would benefit from bypass surgery. Methods: A total of 70 esophageal cancer patients who could not tolerate oral feeding due to esophageal stenosis or tracheoesophageal fistula underwent palliative treatment [esophageal bypass surgery (N = 34) and esophageal stent insertion (N = 36)] at Kumamoto University. We retrospectively investigated the clinicopathological factors, postoperative outcomes, and complications. Results: Both treatments could significantly improve the amount of food intake and the dietary form (P < 0.01). The length of hospital stay was shorter (P < 0.01) and complications associated with treatment were reduced in the stent group (P = 0.03). The overall survival did not differ significantly between the groups (log rank P = 0.22). Importantly, in the bypass surgery group, the patients who received postoperative treatment had a better prognosis than those who did not receive postoperative treatment (log rank P < 0.01). Conclusion: Both bypass surgery and stent insertion allowed oral intake in patients who could not tolerate oral feeding because of esophageal stenosis or tracheoesophageal fistula. Considering that patients who undergo stent insertion have a shorter hospital stay and fewer complications, stent insertion may be a better first choice for treatment than bypass surgery. However, bypass surgery may be an option for patients who can tolerate postoperative treatment. [ABSTRACT FROM AUTHOR]

The hydrosilylation of alkenes is one of the most important methods for the synthesis of organosilicon compounds. In addition to the platinum‐catalyzed hydrosilylation, silyl radical addition reactions are notable as economic reactions. An efficient and widely applicable silyl radical addition reaction was developed by using 2‐silylated dihydroquinazolinone derivatives under photocatalytic conditions. Electron‐deficient alkenes and styrene derivatives underwent hydrosilylation to give addition products in good to high yields. Mechanistic studies indicated that the photocatalyst functioned not as a photoredox catalyst but as an energy transfer catalyst. DFT calculations clarified that the triplet excited state of 2‐silylated dihydroquinazolinone derivatives released a silyl radical through the homolytic cleavage of a carbon‐silicon bond, and this was followed by the hydrogen atom transfer pathway, not the redox pathway. [ABSTRACT FROM AUTHOR]

Background: Regorafenib and TAS-102 are standard salvage-line treatment options for patients with chemorefractory metastatic colorectal cancer (mCRC). We aimed to evaluate the prognostic significance of skeletal muscle mass in mCRC patients receiving these salvage-line therapies. Methods: We conducted a retrospective analysis of 52 patients with mCRC who received regorafenib or TAS-102 as salvage-line treatment. Skeletal muscle cross-sectional area was measured by pretreatment CT to obtain the skeletal muscle index (SMI, cm2/m2). We divided patients into 2 groups (low-SM/high-SMI) based on the median value of SMI. Result: The median SMI was 51.8 cm2/m2 in males and 39.2 cm2/m2 in females. In Kaplan-Meier analysis, patients in the low-SMI group showed significantly shorter overall survival (3.7 vs. 7.3 months, log-rank p = 0.002) and progression-free survival (1.9 vs. 2.8 months, log-rank test p = 0.009) than those in the high-SMI group. Subsequent multivariate analysis revealed that the SMI was an independent prognostic factor (hazard ratio = 2.381, 95% CI 1.189–4.944, p = 0.014). Patients in the low-SMI group had significantly more grade 3 or 4 adverse events than those in the high-SMI group (46 vs.12%, p = 0.013). Conclusion: Low skeletal muscle mass is a negative factor for survival outcomes in mCRC patients treated with salvage-line chemotherapy. [ABSTRACT FROM AUTHOR]

The oxidative kinetic resolution involves an asymmetric intermolecular hydride transfer from indoline to an iminium intermediate generated from indoline and the salicylaldehyde reagent. [ABSTRACT FROM AUTHOR]

Attempted asymmetric reductive amination of benzyl methyl ketones with benzothiazoles (II) as hydrogen donor does not give any yields of the expected β-arylamine whereas phenyl methyl ketone gives the reductive amination product (VII) with moderate e.e. [ABSTRACT FROM AUTHOR]

Review: [17 refs. [ABSTRACT FROM AUTHOR]

Review: 246 refs. [ABSTRACT FROM AUTHOR]

The article reports on the inverse electron-demand aza Diels-Alder reaction of azabutadiene with an electron-rich alkene which is an efficient method in preparing tetrahydroquinoline derivative. Such derivative exhibits antitumor activity and is a core structure of the compounds possessing 5-lipoxygenase inhibitory properties and potential therapeutic application in asthma.

The article presents information about the low-valent niobium-mediated double activation of carbon-fluorine and carbon-hydrogen bonds. The carbon-fluorine bond is believed to be the strongest single bond connected to carbon. The authors have developed a double carbon-fluorine and carbon-hydrogen bond activation protocol for ortho-arylated trifluorotolunes. Further, it is reported that with the help of a low-valent niobium-mediated system, a diverse variety of substituted fluorenes were also developed. The niobium-mediated cyclization often contributes to the areas of research that deal with the synthesis of fluorenes.

Describes a novel approach to the cycloaddition reaction of alkenyl Fischer carbene complexes with simple imines. Production of 3-alkoxy-2,5-disubstituted-3-pyrroline derivatives in high yields due to the reaction; Application of the reaction to one-pot, three-component synthesis of 3-pyrroline derivatives.

Fibroblast activation protein (FAP) generally shows low or undetectable expression in most normal tissues but is highly expressed in fibroblasts in almost all carcinomas. FAP is one of the potential molecules to detect activated fibroblasts and has multiple roles in tumour progression. We generated transgenic mice that specifically expressed tdTomato along with FAP promoter activity. Coculturing a mouse gastric cancer cell line and FAP‐tdTomato transgenic mouse‐derived fibroblasts showed that tdTomato expression was elevated in the cocultured fibroblasts. Moreover, stomach wall transplanted tumours in mice also showed FAP‐tdTomato expression in fibroblasts of the stomach and each metastatic legion. These results indicated that FAP‐tdTomato expression in fibroblasts was elevated by stimulation through the interaction with cancer cells. Functionally, collagen production was increased in FAP/tdTomato‐positive fibroblasts cocultured with mouse cancer cells. These FAP‐tdTomato transgenic mice have the potential to be used to investigate real‐time FAP dynamics and the importance of FAP expression in tumour development. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Phosphoric Acid Bridged Cobalt Bis(dicarbollide) Ion as a Highly Efficient Catalyst for the Organocatalytic Hydrogenation of Ketimines" by T. Akiyama and others, published in the journal "Synlett" in 2014.

The article presents chemical structures of hydrocarbons representing hydrodefluorinations of trifluorotoluenes by lithiumaluminium hydride (LiAlH4) and titanium tetrachloride (TiCl4).

Background: Remodeling the tumor microenvironment (TME) to benefit cancer cells is crucial for tumor progression. Although diffuse-type gastric cancer (DGC) preferentially interacts with the TME, the precise mechanism of the complicated network remains unknown. This study aimed to investigate the mutual activation mechanism underlying DGC progression. Methods: Mass cytometry analysis of co-cultured macrophages, noncancerous fibroblasts (NFs), and DGC cells was performed. RNA sequencing was applied to examine gene expression in fibroblasts. DGC cells were treated with cytokines to examine their effect on characteristic changes. The TCGA and Kumamoto University cohorts were used to evaluate the clinical relevance of the in vitro findings. Results: Cohort analysis revealed that DGC patients had a poor prognosis. The fibroblasts and macrophages interacted with DGC cells to form a cell cluster in the invasive front of DGC tissue. The original 3D triple co-culture system determined the promotional effects of nonmalignant cells on DGC invasive growth. We notably identified a mixed-polarized macrophage cell type with M1/M2 cell surface markers in a triple co-culture system. IL-1β from mixed-polarized macrophages induced the conversion of NFs to cancer-associated fibroblast-like (CAF-like) cells, promoting the malignant phenotype of DGC cells by inducing the secretion of IL-6, IL-24, and leukemia inhibitory factor (LIF). Moreover, IL-6 and colony stimulating factor 2 (GM-CSF) cooperated to maintain the stable state of mixed-polarized macrophages. Finally, we found that mixed-polarized macrophages were frequently detected in DGC tissues. Conclusion: These findings demonstrated that mixed-polarized macrophages exist as a novel subtype through the reciprocal interaction between DGC cells and nonmalignant cells. [ABSTRACT FROM AUTHOR]

Background: Advanced lung cancer inflammation index (ALI) is reported to be a prognosticator in various cancer patients with chemotherapy. However, the clinical impact of the ALI on treatment strategies in metastatic colorectal cancer (mCRC) patients remains unclear. Methods: A total of 356 patients, who received first-line chemotherapy for mCRC between April 2005 and November 2019 in a single institution, were retrospectively enrolled. The association of pretreatment ALI (calculated as follows: BMI × albumin value/neutrophil-to-lymphocyte ratio) status with clinicopathological factors and patient survival outcome was analyzed, using subgroup analysis. Results: The ALI-low cases were significantly associated with female sex, more synchronous metastasis, multiple metastatic sites, less primary tumor resection, less liver resection after chemotherapy, and poor overall survival (OS). A multivariate Cox proportional hazards analysis clarified that the ALI-low status was independently associated with poor OS (HR: 1.78, 95% CI 1.27–2.48, P = 0.001), in addition to right side tumor, multiple metastatic sites, and the non-performance of liver resection after chemotherapy. A subgroup analysis revealed that primary tumor resection and the resection of liver metastases after chemotherapy could not improve the prognosis of ALI-low cases in comparison with ALI-high cases, and the type of first-line chemotherapy did not significantly affect the association between the prognosis and the ALI status. Conclusion: ALI comprehensively evaluates the prognostic host status and is a reliable prognosticator for the mCRC patients with chemotherapy. Calculating pretreatment ALI may serve as a cost-effective and easily available tool for constructing treatment strategies. [ABSTRACT FROM AUTHOR]

Review: 174 refs. [ABSTRACT FROM AUTHOR]

A highly enantioselective protocol for the reductive amination of aliphatic ketones with aromatic amines catalyzed by a chiral phosphoric acid is presented. [ABSTRACT FROM AUTHOR]

Reported herein is an enantiodivergent synthesis of chiral biaryls by a chiral phosphoric acid catalyzed asymmetric transfer hydrogenation reaction. Upon treatment of biaryl lactols with aromatic amines and a Hantzsch ester in the presence of chiral phosphoric acid, dynamic kinetic resolution (DKR) involving a reductive amination reaction proceeded smoothly to furnish both R and S isomers of chiral biaryls with excellent enantioselectivities by proper choice of hydroxyaniline derivative. This trend was observed in wide variety of substrates, and various chiral biphenyl and phenyl naphthyl adducts were synthesized with satisfactory enantioselectivities in enantiodivergent fashion. The enantiodivergent synthesis of synthetically challenging, chiral o-tetrasubstituted biaryls were also accomplished, and suggests high synthetic potential of the present method. [ABSTRACT FROM AUTHOR]

Reported herein is an enantiodivergent synthesis of chiral biaryls by a chiral phosphoric acid catalyzed asymmetric transfer hydrogenation reaction. Upon treatment of biaryl lactols with aromatic amines and a Hantzsch ester in the presence of chiral phosphoric acid, dynamic kinetic resolution (DKR) involving a reductive amination reaction proceeded smoothly to furnish both R and S isomers of chiral biaryls with excellent enantioselectivities by proper choice of hydroxyaniline derivative. This trend was observed in wide variety of substrates, and various chiral biphenyl and phenyl naphthyl adducts were synthesized with satisfactory enantioselectivities in enantiodivergent fashion. The enantiodivergent synthesis of synthetically challenging, chiral o-tetrasubstituted biaryls were also accomplished, and suggests high synthetic potential of the present method. [ABSTRACT FROM AUTHOR]

A chiral calcium phosphate-catalyzed enantioselective Friedel–Crafts alkylation reaction of pyrroles and α-trifluoromethyl-β-nitrostyrenes has been developed. Pyrroles bearing an all-carbon quaternary center at 2-position were obtained with high to excellent enantioselectivity. Use of 4,7-dihydroindole as a nucleophile and subsequent oxidation resulted in the formation a 2-substituted indole derivative with excellent enantioselectivity. A 3,4-dihydropyrrolo[1,2- c ]pyrimidine derivative was successfully synthesized by reduction followed by benzoylation of the product without loss of enantioselectivity. Application to a 1 mmol scale reaction was successfully achieved. [ABSTRACT FROM AUTHOR]

The titanium tetrachloride-catalyzed hydrodefluorination reaction of trifluorotoluene derivatives was developed using triethylsilane as the reducing agent. The reaction produced various toluene derivatives with high chemoselectivities by means of readily accessible reagents. This hydrodefluorination process was extended to the intramolecular Friedel-Crafts benzylation reaction, furnishing polycyclic aromatics of various ring sizes in good yields. [ABSTRACT FROM AUTHOR]

A chiral Brønsted acid catalyzed dehydrogenative kinetic resolution of tetrahydroquinoline derivatives, which are representative of cyclic secondary amines, based on their hydrogen transfer to aromatic imines was efficiently achieved with high enantioselectivities. This hydrogen transfer of tetrahydroquinolines to imines was not driven by their aromatization to quinolines. This dehydrogenative kinetic resolution could be also applied to the asymmetric synthesis of various benzofused heterocycles containing secondary amine cores. [ABSTRACT FROM AUTHOR]

Described herein is a highly enantioselective synthesis of fused piperidine and pyrrolidine derivatives with all-carbon stereogenic centers. The enantioselective reductive amination from Cs-symmetric 1,3-dione derivatives proceeded in a highly stereoselective manner by taking advantage of the desymmetrization approach to afford fused heterocycles with contiguous stereogenic centers in good to excellent enantioselectivities (up to 98% ee). [ABSTRACT FROM AUTHOR]

Background: Signet ring cell carcinoma (SRCC) is a particular histologic variant of gastric cancer (GC). However, the critical factor related to the aggressive characteristics of SRCC has not been determined. Methods: We collected surgically resected tissues from 360 GC patients in the Kumamoto University cohort and generated survival curves via the Kaplan–Meier method. In vitro, we identified the specific transcript variant of MUC20 in SRCC cells by direct sequencing and investigated the role of MUC20 in GC progression using GC cells with MUC20 silencing and forced expression. In vivo, we examined chemoresistance using MUC20 variant 2 (MUC20v2)-overexpressing non-SRCC cells to construct a xenograft mouse model. Results: We analyzed a comprehensive GC cell line database to identify the specifically expressed genes in gastric SRCC. We focused on MUC20 and investigated its role in GC progression. Survival analysis revealed that GC patients with high MUC20 expression exhibited a poor prognosis and that MUC20 expression was significantly correlated with SRCC histological type. Moreover, we found that gastric SRCC cells specifically expressed MUC20v2, which was dominantly expressed in the cytoplasm. Silencing MUC20v2 caused cell death with characteristic morphological changes in gastric SRCC cells. To further determine the types of cell death, we examined apoptosis, pyroptosis and ferroptosis by detecting cleaved PARP, gasdermin E-N-terminal (GSDME-N), and lipid reactive oxygen species (ROS) levels, respectively. We found that apoptosis and pyroptosis occurred in MUC20-silenced gastric SRCC cells. In addition, MUC20v2-overexpressing GC cells exhibited chemoresistance to cisplatin (CDDP) and paclitaxel (PTX). RNA sequencing revealed that the pathways involved in intracellular calcium regulation were significantly upregulated in MUC20v2-overexpressing GC cells. Notably, forced expression of MUC20v2 in the cytoplasm of GC cells led to the maintenance of mitochondrial calcium homeostasis and mitochondrial membrane potential (MMP), which promoted cell survival and chemoresistance by suppressing apoptosis and pyroptosis. Finally, we investigated the significance of MUC20v2 in a xenograft model treated with CDDP and showed that MUC20v2 overexpression caused chemoresistance by inhibiting cell death. Conclusion: These findings highlight the novel functions of MUC20v2, which may confer cell survival and drug resistance in GC cells. Significance: MUC20v2 protects GC cells from apoptosis and pyroptosis by maintaining mitochondrial calcium levels and mitochondrial membrane potential and subsequently induces drug resistance. [ABSTRACT FROM AUTHOR]

A concise route to 3-aryl-1-trifluoromethyltetrahydroisoquinolines by a benzylic [1,5]-hydride shift-mediated C--H bond functionalization was developed. The [1,5]-hydride shift of the benzylic C(sp3)-H bond to the trifluoromethylketimine derived from para-anisidine occurred smoothly to produce cis-1-trifluoromethyl-3-aryltetrahydroisoquinolines in good to excellent chemical yields with good diastereoselectivities. In contrast, use of the N--H ketimine furnished N-unprotected tetrahydroisoquinolines in good yields in favor of the trans-isomer. [ABSTRACT FROM AUTHOR]

The chiral phosphoricacid catalyzed enantioselective transferhydrogenation of various ketimines was achieved by the use of 2-arylindoline as the hydrogen donor. Corresponding chiral amines were obtainedin good chemical yields with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

A good mix: The title reaction of o‐alkynylacetophenones with the Hantzsch ester in the presence of a chiral copper/phosphate catalyst proceeds in good yields with excellent enantioselectivities. The key intermediate for enantiocontrol is the ion pair of the carbonyl ylide with a chiral phosphate anion, and this process provides straight forward access to highly enantioriched chiral isochromenes. [ABSTRACT FROM AUTHOR]

Gute Mischung: o ‐ Alkinylacetophenone werden in der Titelreaktion mit dem Hantzsch ‐ Ester in guten Ausbeuten erhalten. Das entscheidende Intermediat für die Enantioselektivität ist ein Ionenpaar aus dem Carbonyl ‐ Ylid und einem chiralen Phosphatanion. Der Prozess führt direkt zu hoch enantiomerenangereicherten chiralen Isochromenen. [ABSTRACT FROM AUTHOR]