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This article provides information on several bryophytes. Bryum stenophyllum is a very distinctive little moss with narrow leaves and long cells which are narrower towards the margin, which may be plane narrowly recurved, even on the type. Its leaf should be described as having no distinct border rather than a broad ill-defined one. The capsule is slender and narrow with a rather long, slender neck, resembling some Pohlia species but with well-developed appendiculate cilia. Cirriphyllum cirrosum, on the other hand, can be added to the growing list of bipolar species. It has apparently not been previously found in the southern hemisphere. The habitat would be rather an unfamiliar one to western and central European bryologists, who are more accustomed to seeing it on damp rock ledges or rocky or stony grassy slopes. Didymodon brachyphyllus is another. It has long been considered as a poorly known North American species. In the Northern Hemisphere it is arctic-alpine in distribution, with the main centre of distribution in western North America, from Oregon to Baja California Norte in Mexico east to Colorado and New Mexico, with some isolated stations in British Columbia and in S.W. Alaska on the Alaska Peninsula.

The article presents a discussion on the bryophyte flora of Uganda. The plants form dense mats or cushions, and are rarely intermixed with other bryophytes. They are mostly 5"80 mm high and 0.1"3.5 mm wide, erect or ascending, rarely prostrate and the stems are mostly differentiated into a cortical layer of smaller thick-walled cells, sometimes also with thin-walled hyalodermis of larger cells, and larger medullary cells. Branching is uncommon, mostly lateral-intercalary, sporadically terminal, dorsal-intercalary or ventral-intercalary.

The Eschenmoser coupling reaction (ECR) of thioamides with electrophiles is believed to proceed via thiirane intermediates. However, little is known about converting the intermediates into ECR products. Previous mechanistic studies involved external thiophiles to remove the sulfur atom from the intermediates. In this work, an ECR proceeding without any thiophilic agent or base is studied by electrospray ionization-mass spectrometry. ESI-MS enables the detection of the so-far elusive polysulfide species S n , with n ranging from 2 to 16 sulfur atoms, proposed to be the key species leading to product formation. Integrating observations from ion mobility spectrometry, ion spectroscopy, and reaction monitoring via flow chemistry coupled with mass spectrometry provides a comprehensive understanding of the reaction mechanism and uncovers the autocatalytic nature of the ECR reaction., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

This study presents an improved synthetic route to ligand ( S )-4-( tert -butyl)-2-(5-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole and its application as a highly active and enantioselective catalyst in the addition of arylboronic acids to cyclic N -sulfonylketimines. Immobilization of such a ligand was achieved using a commercially available starting material and a PS-PEG TentaGel S NH 2 support, resulting in a stable heterogeneous catalyst. Although the anchored catalyst exhibited a slight reduction in enantioselectivity and a 4-fold decrease in reaction rate, it displayed remarkable stability, enabling 10 consecutive reaction cycles. Furthermore, the successful transition to a continuous flow system demonstrated even higher turnover numbers compared to batch arrangements. These findings provide valuable insights into the development of efficient flow reactors for continuous synthesis of benzosultams, further advancing the field of asymmetric catalysis.

Simple switching of the site-selectivity of C-H activation reactions of substrates containing multiple directing groups is particularly important for the so-called late stage functionalization synthetic approach. In this work, we verified the possibility of achieving this by adding acids of different strengths. Using a substrate containing two differently strong (and basic) directing groups, the influence of the addition of acids on the regioselectivity of the C-H activation step of the reaction with palladium acetate was thoroughly studied. The addition of no or weak acids results in cyclopalladation being controlled by a stronger directing group. However, the addition of a strong acid causes protonation of this group and the reaction is then controlled by a weaker directing group. Finally, this approach enables double C-H activation leading to a unique class of compounds: "non-symmetrical" [2.2]-dipalladaparacyclophanes.

Reactions of thiobenzamide or thioacetamide with 4-bromo-1,1-dimethyl-1,4-dihydroisoquinoline-3(2 H )-one, 4-bromoisoquinoline-1,3(2 H ,4 H )-dione and two α-bromo(phenyl)acetamides were examined under various conditions (base, solvent, thiophile, temperature) and structure/medium features that influence product distribution (Eschenmoser coupling reaction, Hantzsch thiazole synthesis and elimination to nitriles) were identified. The key factor that enables the successful Eschenmoser coupling reaction involves the optimum balance in acidity of nitrogen and carbon atoms of the intermediary α-thioiminium salts., (Copyright © 2023, Marek et al.)

Palladacycles are key intermediates in catalytic C-H bond functionalization reactions and important precatalysts for cross-couplings. It is commonly believed that palladacycle formation occurs through the reaction of a substrate bearing a C-H bond ortho to a suitable metal-directing group for interaction with, typically, mononuclear "Pd(OAc) 2 " species, with cyclopalladation liberating acetic acid as the side product. In this study, we show that N , N -dimethyl-fluoro-benzyl amines, which can be cyclopalladated either ortho or para to fluorine affording two regioisomeric products, can occur by a direct reaction of Pd 3 (OAc) 6 , proceeding via higher-order cyclopalladated intermediates. Regioselectivity is altered subtly depending on the ratio of substrate:Pd 3 (OAc) 6 and the solvent used. Our findings are important when considering mechanisms of Pd-mediated reactions involving the intermediacy of palladacycles, of particular relevance in catalytic C-H bond functionalization chemistry., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Acute mesenteric ischemia is a disease with a relatively low incidence (0,02-0,9% of acute surgical hospitalizations) but a very high mortality rate which can reach up to 100% without early revascularization. Given the above, prompt and accurate diagnosis and subsequent surgical intervention is the cornerstone of treatment and essential to reduce the high mortality rate. Early revascularization can reduce overall mortality by up to 50%. Treatment of acute mesenteric ischemia requires the cooperation of gastrointestinal surgeons, vascular surgeons and interventional radiologists. Thorough clinical examination, contrast computed tomography performed at the initial stage, and the current possibilities of interventional radiology are the keys to improving the results of treatment of acute mesenteric ischemia. The purpose of this paper is to refresh knowledge in the management of acute mesenteric ischemia and summarize the most up-to-date information on the diagnosis and treatment of this disease.

Irradiation of coumarin-3-carboxylic acid in acetonitrile and methanol solutions at 355 nm results in complex multistep photochemical transformations, strongly dependent on the solvent properties and oxygen content. A number of reaction intermediates, which themselves undergo further (photo)chemical reactions, were identified by steady-state and transient absorption spectroscopy, mass spectrometry, and NMR and product analyses. The triplet excited compound in acetonitrile undergoes decarboxylation to give a 3-coumarinyl radical that traps molecular oxygen to form 3-hydroxycoumarin as the major but chemically reactive intermediate. This compound is oxygenated by singlet oxygen, produced by coumarin-3-carboxylic acid sensitization, followed by a pyrone ring-opening reaction to give an oxalic acid derivative. The subsequent steps lead to the production of salicylaldehyde, carbon monoxide, and carbon dioxide as the final products. When 3-coumarinyl radical is not trapped by oxygen in degassed acetonitrile, it abstracts hydrogen from the solvent and undergoes triplet-sensitized [2 + 2] cycloaddition. The reaction of 3-coumarinyl radical with oxygen is largely suppressed in aerated methanol as a better H-atom donor, and coumarin is obtained as the primary product in good yields. Because coumarin derivatives are used in many photophysical and photochemical applications, this work provides detailed and sometimes surprising insights into their complex phototransformations., (© 2022. The Author(s), under exclusive licence to European Photochemistry Association, European Society for Photobiology.)

The novel dimeric iodo-iridium(III) complex, [Ir(Cp*CONMe 2 )I 2 ] 2 , (Cp*CONMe 2 = η 5 - N,N -2,3,4,5-hexamethylcyclopenta-2,4-diene carboxamide) bearing an amide moiety within the tetramethylcyclopentadiene ring, has been synthesised and characterised. The ligand Cp*CONMe 2 is synthesised as two regioisomers, however the 2-substituted isomer exists as two distinguishable conformers due to restricted rotation about the amide carbonyl carbon and the ring carbon. The relative acidities of Cp*CONMe 2 and Cp* are compared by their relative rates of H/D exchange. The iridium complex of N,N -2,3,4,5-hexamethylcyclopenta-2-4-diene carboxamide [IrCp*CONMe 2 ] and ( R,R )-1,2-diphenyl- N '-tosylethane-1,2-diamine (( R , R )-TsDPEN) has been evaluated in the transfer hydrogenation of imines under acidic conditions - a 5 : 2 molar ratio of formic acid : triethylamine as the hydride source for the transfer hydrogenation of 1-methyl-3,4-dihydroisoquinoline (DHIQ) and its 6,7-dimethoxy derivative in acetonitrile. A decreasing enantiomeric excess with reaction progress is attributed to different kinetic orders for formation of the two product amine enantiomers. The pseudo zero-order formation of the R -amine may be due to a pre-steady-state formation of the less stable form of the diastereomeric catalyst. By contrast, both enantiomeric amines from 1-fluorinated methyl DHIQs as substrates for reduction are formed by pseudo first-order processes.

Dehiscence of colorectal anastomosis is a serious complication that is associated with increased mortality, impaired functional and oncological outcomes. The hypothesis was that anastomosis reinforcement and vacuum trans-anal drainage could eliminate some risk factors, such as mechanically stapled anastomosis instability and local infection. Patients with rectal cancer within 10 cm of the anal verge and low anterior resection with double-stapled technique were included consecutively. A stapler anastomosis was supplemented by trans-anal reinforcement and vacuum drainage using a povidone-iodine-soaked sponge. Modified reinforcement using a circular mucosa plication was developed and used. Patients were followed up by postoperative endoscopy and outcomes were acute leak rate, morbidity, and diversion rate. The procedure was successfully completed in 52 from 54 patients during time period January 2019-October 2020. The mean age of patients was 61 years (lower-upper quartiles 54-69 years). There were 38/52 (73%) males and 14/52 (27%) females; the neoadjuvant radiotherapy was indicated in a group of patients in 24/52 (46%). The mean level of anastomosis was 3.8 cm (lower-upper quartiles 3.00-4.88 cm). The overall morbidity was 32.6% (17/52) and Clavien-Dindo complications ≥ 3 grade appeared in 3/52 (5.7%) patients. No loss of anastomosis was recorded and no patient died postoperatively. The symptomatic anastomotic leak was recorded in 2 (3.8%) patients and asymptomatic blind fistula was recorded in one patient 1/52 (1.9%). Diversion ileostomy was created in 1/52 patient (1.9%). Reinforcement of double-stapled anastomosis using a circular mucosa plication with combination of vacuum povidone-iodine-soaked sponge drainage led to a low acute leak and diversion rate. This pilot study requires further investigation.Registered at ClinicalTrials.gov.: Trial registration number is NCT04735107, date of registration February 2, 2021, registered retrospectively., (© 2021. The Author(s).)

A novel synthetic approach involving an Eschenmoser coupling reaction of substituted 3-bromooxindoles (H, 6-Cl, 6-COOMe, 5-NO 2 ) with two substituted thiobenzanilides in dimethylformamide or acetonitrile was used for the synthesis of eight kinase inhibitors including Nintedanib and Hesperadin in yields exceeding 76%. Starting compounds for the synthesis are also easily available in good yields. 3-Bromooxindoles were prepared either from corresponding isatins using a three-step synthesis in an average overall yield of 65% or by direct bromination of oxindoles (yield of 65-86%). Starting N -(4-piperidin-1-ylmethyl-phenyl)-thiobenzamide was prepared by thionation of the corresponding benzanilide in an 86% yield and N -methyl- N -(4-thiobenzoylaminophenyl)-2-(4-methylpiperazin-1-yl)acetamide was prepared by thioacylation of the corresponding aniline with methyl dithiobenzoate in an 86% yield.

The transition metal (palladium)-catalysed asymmetric 1,4-addition of arylboronic acids to conjugated enones belong to the most important and emerging strategies for the construction of C-C bonds in an asymmetric fashion. This review covers known catalytic systems used for this transformation. For clarity, we are using the type of ligand as a sorting criterion. Finally, we attempted to create a flowchart facilitating the selection of a suitable ligand for a given combination of enone and arylboronic acid., (Copyright © 2021, Bartáček et al.)

Plasmon assistance promotes a range of chemical transformations by decreasing their activation energies. In a common case, thermal and plasmon assistance work synergistically: higher temperature results in higher plasmon-enhanced catalysis efficiency. Herein, we report an unexpected tenfold increase in the reaction efficiency of surface plasmon-assisted Huisgen dipolar azide-alkyne cycloaddition (AAC) when the reaction mixture is cooled from room temperature to -35 °C. We attribute the observed increase in the reaction efficiency to complete plasmon-induced annihilation of the reaction barrier, prolongation of plasmon lifetime, and decreased relaxation of plasmon-excited-states under cooling. Furthermore, control quenching experiments supported by theoretical calculations indicate that plasmon-mediated substrate excitation to an electronic triplet state may play the key role in plasmon-assisted chemical transformation. Last but not least, we demonstrated the possible applicability of plasmon assistance to biological systems by AAC coupling of biotin to gold nanoparticles performed at -35 °C., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A highly modular method for the synthesis of ( Z )-3-[amino(phenyl/methyl)methylidene]-1,3-dihydro-2 H -indol-2-ones starting from easily available 3-bromooxindoles or (2-oxoindolin-3-yl)triflate and thioacetamides or thiobenzamides is described. A series of 49 compounds, several of which have previously been shown to possess significant tyrosin kinase inhibiting activity, was prepared in yields varying mostly from 70 to 97% and always surpassing those obtained by other published methods. The method includes an Eschenmoser coupling reaction, which is very feasible (even without using a thiophile except tertiary amides) and scalable. The ( Z )-configuration of all products was confirmed by NMR techniques., (Copyright © 2021, Marek et al.)

Leaving groups attached to the meso-methyl position of many common dyes, such as xanthene, BODIPY, or pyronin derivatives, can be liberated upon irradiation with visible light. However, the course of phototransformations of such photoactivatable systems can be quite complex and the identification of reaction intermediates or even products is often neglected. This paper exemplifies the photochemistry of a 9-dithianyl-pyronin derivative, which undergoes an oxidative transformation at the meso-position to give a 3,6-diamino-9H-xanthen-9-one derivative, formic acid, and carbon monoxide as the main photoproducts. The course of this multi-photon multi-step reaction was studied under various conditions by steady-state and time-resolved optical spectroscopy, mass spectrometry and NMR spectroscopy to understand the effects of solvents and molecular oxygen on individual steps. Our analyses have revealed the existence of many intermediates and their interrelationships to provide a complete picture of the transformation, which can bring new inputs to a rational design of new photoactivatable pyronin or xanthene derivatives., (© 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)