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Combining chemical reactivities of allenes and oximes created a methodology for the preparation of heterocyclic triquinane‐type skeletons via a cascade process constructing four bonds in a single step. The initial reaction of allene moiety promoted by Pd‐catalysis, affording π‐allyl Pd‐species, was followed by two additional transformations ‐ nucleophilic displacement and dipolar cycloaddition ‐ to furnish the product highly stereoselectively in moderate to good yields. For the process to be efficient, it was necessary to use a dipolarophilic component as a solvent. Intriguingly, while the reaction with cyclopentanone derived oxime progressed through the whole cascade, with cyclohexanone analogue it stopped at the nitrone stage, requiring an additional step to yield similar type of products. Some aspects of the studied cascade were examined by DFT. [ABSTRACT FROM AUTHOR]

Enallenylamides have been utilized for the synthesis of heterobicycle[4.2.0]octane derivatives via Ir/hν promoted [2+2] cycloaddition reaction. The reaction specifically targets the distal double bond of the allene moiety, and results in the exclusive formation of the trans product. The process is conducted at room temperature and under an inert atmosphere. An extensive study on the substituent propensities during the cycloaddition step revealed variable effects. Electron‐withdrawing groups conjugated with the double bond participating in the cycloaddition either hindered the process or reduced its yield. Conversely, electron‐donating substituents enhanced the efficiency, resulting in product yields ranging from 60% to 88%. Our study also demonstrated the influence of protecting groups on the reaction pathway. [ABSTRACT FROM AUTHOR]

The article in Advanced Synthesis & Catalysis discusses the synthesis of angular heterotriquinane derivatives through a three-component cascade process involving palladium-catalyzed transformations and dipolar cycloadditions. The front cover picture symbolizes the cascade transformation with a waterfall, representing the in-situ transformations of the starting oxime to produce the final product. The process creates four new bonds in a single operation and is detailed in the work by P. Jovanovic, V. Savic, and their co-workers. [Extracted from the article]

Purpose: The aim of the paper was to develop the simple procedures for preparation of inclusion complexes of ellagic acid (EA) with cyclodextrins (CDs) and to investigate their antioxidant and antimicrobial activity. Methods: The structural characterization was carried out using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and nuclear magnetic resonance (NMR) methods. The phase solubility technique was used to investigate the interactions between 'host' and 'guest' molecules and to estimate the molar ratio between them. The antioxidant and antimicrobial activity of EA and inclusion complexes were determined. Results: The apparent stability constants were found to be 117 dm3 mol−1 for the complex with β-CD and 161 dm3 mol−1 for the complex with (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD). The results of phase-solubility studies showed that EA formed the inclusion complexes with CDs in the molar ratio of 1:1. The calculated half-maximal inhibitory concentration was 41.18 μg cm−3 for butyl hydroxy toluene, 1.96 μg cm−3 for EA, 0.88 μg cm−3 for inclusion complex with HP-β-CD, and 1.27 μg cm−3 for inclusion complex with β-CD. Conclusion: The stability constants indicated the rapid release of EA from the inclusion complexes in the aqueous medium at 25 °C. The antioxidant activity of EA was increased, while the antimicrobial activity was preserved after complexation with CDs. [ABSTRACT FROM AUTHOR]

Objectives: An inclusion complex of biochanin A (BCA) with (2‐hydroxypropyl)‐β‐cyclodextrin (HP‐β‐CD) was prepared in the ethanol solution to improve its water solubility. Methods: Using the FTIR, 1H‐NMR, XRD, DSC and SEM methods, the structural characterization of the prepared complex was analysed. Key findings: The phase‐solubility study has shown that the solubility of BCA was increased twofold in 42% (v/v) ethanol solution after complexation with HP‐β‐CD. The complex between BCA and HP‐β‐CD was prepared in the molar ratio of 1 : 1. The antibacterial activity of the inclusion complex was investigated against the various bacteria, fungus and yeast using the microdilution method. The minimal inhibitory concentration values for the analysed strain of bacteria were in the range of 0.84–1.69 mg/cm3, whereby the prepared inclusion complex exhibited less effect on the reduction of the number of Escherichia coli and Klebsiella pneumoniae species compared to pure BCA. The inclusion complex of BCA was significantly more active against Candida albicans than pure BCA. Biochanin A and its inclusion complex has not expressed the activity against Aspergillus niger. Conclusions: Based on the obtained results, it can be concluded that the antimicrobial activity of BCA was remained unchanged after complexation. [ABSTRACT FROM AUTHOR]

Presacral venous hemorrhage is a severe complication in low rectal surgery. This complication was encountered in 5 of 165 patients (3 percent) who underwent a presacral dissection for rectal mobilization. Conventional hemostatic measures often are ineffective to arrest this hemorrhage, and a number of alternative hemostatic techniques have been proposed. We report the successful tamponade of presacral hemorrhage with absorbable hemostatic sponges fixed to the sacrum with endoscopic helical tackers. [ABSTRACT FROM AUTHOR]

Describes an unusual complication of the use of laparoscopic trocars under computed tomographic guidance for percutaneous extraction of a foreign body from an infected liver cyst. Retention of the tip of the drain in the cyst after removal; Probability of the recurrence of the cyst; Extraction of the foreign body from the liver cyst under local anesthesia.