Mcleodmccullough7857

The tri(n-butyl)phosphine-catalyzed reaction of isatylidene malononitriles and bis-chalcones in chloroform at 65 °C afforded functionalized spiro[cyclohexane-1,3'-indolines] in good yields and with good diastereoselectivity. On the other hand, the tri(n-butyl)phosphine-catalyzed reaction of 3-(ethoxycarbonylmethylene)oxindoles and bis-chalcones gave functionalized spiro[cyclohexane-1,3'-indolines] with different regioselectivity. Additionally, the tri(n-butyl)phosphine-promoted domino annulation reaction of isatins and ethyl isatylidene cyanoacetates produced spiro[indoline-3,2'-furan-3',3-indolines] in satisfactory yields.The direct and selective mechanochemical halogenation of C-H bonds in unsymmetrically substituted azobenzenes using N-halosuccinimides as the halogen source under neat grinding or liquid-assisted grinding conditions in a ball mill has been described. Depending on the azobenzene substrate used, halogenation of the C-H bonds occurs in the absence or only in the presence of PdII catalysts. Insight into the reaction dynamics and characterization of the products was achieved by in situ Raman and ex situ NMR spectroscopy and PXRD analysis. A strong influence of the different 4,4'-substituents of azobenzene on the halogenation time and mechanism was found.A method has been developed for the preparation of 2-alkyl-6-aryl-, 2-aryl-6-aryl and 2,6-diaryl-5-aryl/hetaryl-substituted methyl 4-oxo-1,4-dihydropyridine-3-carboxylates by Mo(CO)6-mediated ring expansion of methyl 2-(isoxazol-5-yl)-3-oxopropanoates. The high reactivity of 4-oxo-1,4-dihydropyridine-3-carboxylates synthesized provide easy access to 2,4,6-triaryl-substituted and 1,2,5,6-tetrasubstituted nicotinates.Aromatic prenylated metabolites have important biological roles and activities in all living organisms. Compared to their importance in all domains of life, we know relatively little about their substrate scopes and metabolic functions. Here, we describe a new UbiA-like prenyltransferase (Ptase) Ubi-297 encoded in a conserved operon of several bacterial taxa, including marine Flavobacteria and the genus Sacchromonospora. In silico analysis of Ubi-297 homologs indicated that members of this Ptase group are composed of several transmembrane α-helices and carry a conserved and distinct aspartic-rich Mg2+-binding domain. We heterologously produced UbiA-like Ptases from the bacterial genera Maribacter, Zobellia, and Algoriphagus in Escherichia coli. Investigation of their substrate scope uncovered the preferential farnesylation of quinoline derivatives, such as 8-hydroxyquinoline-2-carboxylic acid (8-HQA) and quinaldic acid. The results of this study provide new insights into the abundance and diversity of Ptases in marine Flavobacteria and beyond.Inductive heating has developed into a powerful and rapid indirect heating technique used in various fields of chemistry, but also in medicine. Traditionally, inductive heating is used in industry, e.g., for heating large metallic objects including bending, bonding, and welding pipes. In addition, inductive heating has emerged as a partner for flow chemistry, both of which are enabling technologies for organic synthesis. This report reviews the combination of flow chemistry and inductive heating in industrial settings as well as academic research and demonstrates that the two technologies ideally complement each other.The enhanced reaction rate in the epoxidation of cyclohexene with air as an oxidant was discovered without any added catalyst utilizing a continuous flow reactor constructed with readily available stainless steel parts and devices. This continuous-flow process demonstrates a significant improvement in reaction time for highly selective epoxide production over the batch process due to the efficient mass transfer between the liquid phase and air. The flow process discovered was operated continuously with good operational stability, evaluated by a constant high yield of cyclohexene oxide, to obtain the desired product with high productivity.The solution phase 1,2-debromination of polycyclic imides using the Zn/Ag couple was successfully transferred to solid state mechanochemical conditions. The Zn/Ag couple was replaced by the Zn/Cu couple which was prepared without any metal activation by in situ ball milling of zinc and copper dusts. The advantage of the ball milling process is that the whole procedure is operationally very simplified. The reactive alkene generated was trapped in situ by several dienes and the respective Diels-Alder cycloadducts were obtained. It was demonstrated that mechanochemical milling offers complementary conditions to solution (thermal) reaction by allowing chemical transformations to proceed which were not possible in solution and vice versa.Isocyanides are hardly produced, dramatically sensitive to purification processes, and complex to handle as synthetic tools. Notwithstanding, they represent one of the most refined and valuable compounds for accessing sophisticated and elegant synthetic routes. A unique interest has always been addressed to their production, though their synthetic pathways usually involve employing strong conditions and toxic reagents. The current paper intends to provide a conceptually innovative synthetic protocol for mechanochemical isocyanide preparation, simultaneously lowering the related reagents' toxicity and improving their purification in a straightforward procedure.Endoperoxide natural products are widely distributed in nature and exhibit various biological activities. Due to their chemical features, endoperoxide and endoperoxide-derived secondary metabolites have attracted keen attention in the field of natural products and organic synthesis. In this review, we summarize the structural analyses, mechanistic investigations, and proposed reaction mechanisms of endoperoxide-forming oxygenases, including cyclooxygenase, fumitremorgin B endoperoxidase (FtmOx1), and the asnovolin A endoperoxygenase NvfI.

Vascular invasion is a well-known independent prognostic factor in colon cancer and tumor sidedness is also being considered a prognostic factor. The aim of this study was to compare the oncological impact of vascular invasion depending on the tumor location in stages I to III colon cancer.

A retrospective analysis was performed using data from patients who underwent curative resection between 2004 and 2015. Patients were divided into right-sided colon cancer (RCC) and left-sided colon cancer (LCC) groups according to the tumor location. Disease-free survival (DFS) and overall survival (OS) were compared between the RCC and LCC groups, depending on the presence of vascular invasion.

A total of 793 patients were included, of which 304 (38.3%) had RCC and 489 (61.7%) had LCC. DFS and OS did not differ significantly between the RCC and LCC groups. Vascular invasion was a poor prognostic factor for DFS in both RCC (hazard ratio [HR], 2.291; 95% confidence interval [CI], 1.186-4.425;

= 0.010) and LCC (HR, 1.848; 95% CI, 1.139-2.998;

= 0.011). Additionally, it was associated with significantly worse OS in the RCC (HR, 3.503; 95% CI, 1.681-7.300;

< 0.001), but not in the LCC group (HR, 1.676; 95% CI, 0.885-3.175;

= 0.109). Multivariate analysis revealed that vascular invasion was independently poor prognostic factor for OS in the RCC (HR, 3.186; 95% CI, 1.391-7.300;

= 0.006).

This study demonstrated that RCC with vascular invasion had worse OS than LCC with vascular invasion.

This study demonstrated that RCC with vascular invasion had worse OS than LCC with vascular invasion.Acute cholecystitis (AC) is the most common biliary tract disease, and laparoscopic cholecystectomy (LC) is recognized as the treatment of choice. The present study in this issue compared the surgical outcomes, particularly the occurrence of postoperative surgical site infections (SSIs) in patients with and without drain placement following complicated LC for AC. It showed that late drain removal demonstrated significantly worse surgical outcomes than no drain placement and early drain removal for overall complications, postoperative hospital stay, and SSIs. Drain placement is not routinely recommended, even after complicated LC for AC. When placing a drain, early drain removal is recommended for postoperative outcomes such as SSIs.Transduodenal ampullectomy (TDA) is the treatment of choice for large premalignant lesions of the ampulla of Vater (AoV). With the development of surgical techniques, various methods, including the open, laparoscopic, and robotic approaches, for performing TDA have emerged. Herein, we report four consecutive cases treated with open, laparoscopic, and robotic TDA, with technical pitfalls and future perspectives of TDA in treating premalignant lesions of the AoV. The surgical techniques and principles for TDA were the same regardless of the surgical approaches. After surgery, none of the patients showed any abnormal findings or complications, except for digestive problems. All these surgical approaches are appropriate for patients requiring TDA; however, minimally invasive TDA, particularly the robotic approach is ideal. Considering the surgical complexity of TDA, the robotic approach is considered to be effective.While laparoscopic colonoscopy was reported by several surgeons in the early 1990s, laparoscopic colorectal surgery has been attempted sporadically since 1992 in Korea. Then, in 2000, the Korean Laparoscopic Colorectal Surgery Study Group was established. Didactic lectures, videos, and live surgery by the early pioneers of this group inspired and helped many surgeons initiate the laparoscopic approach to the treatment of colorectal disease. As a result, the penetration rate of minimally invasive colorectal cancer surgery nationwide is increasing to 80% in 2018. As a witness on this journey, I would like to share my personal minimally invasive colorectal cancer surgery history and perspectives on future surgery in this field.Chronic posttraumatic diaphragmatic hernia is an unusual disease with challenging diagnosis and treatment. Surgery represents the treatment of choice which can be transabdominal, transthoracic, or combined approach. The principles of surgery consist of herniated visceral organs reduction and diaphragmatic defect closure. This video demonstrates the steps of chronic posttraumatic diaphragmatic hernia repair via a laparoscopic approach and concerning points during the operation.

This study was performed to investigate the effect of drain placement on complicated laparoscopic cholecystectomy (cLC) for acute cholecystitis (AC).

This single-center retrospective study reviewed patients with AC who underwent cLC between January 2010 and December 2020. cLC was defined as open conversion, subtotal cholecystectomy, adjacent organ injury during surgery, operation time of ≥90 minutes, or estimated blood loss of ≥100 mL. One-to-one propensity score matching was performed to compare the surgical outcomes between patients with and without drain on cLC.

A total of 216 patients (mean age, 65.8 years; 75 female patients [34.7%]) underwent cLC, and 126 (58.3%) underwent intraoperative abdominal drainage. In the propensity score-matched cohort (61 patients in each group), early drain removal (≤postoperative day 3) was performed in 42 patients (68.9%). selleck chemicals llc The overall rate of surgical site infection (SSI) was 10.7%. Late drain removal demonstrated significantly worse surgical outcomes than no drain placement and early drain removal for overall complications (13.