Emergence of a New NNN Pincer Ligand via Si-H-Bond Activation and b-Hydride Abstraction at Tetravalent Cerium.

Emergence of a New [NNN] Pincer Ligand via Si-H-Bond Activation and b-Hydride Abstraction at Tetravalent Cerium. Chemistry. 2020 Apr 02;: Authors: Werner D, Bayer U, Schädle D, Anwander R Abstract The  cerium(IV) pyrazolate complexes [Ce(Me 2 pz) 4 ] 2  and [Ce(Me 2 pz) 4 (thf)] initiate  b -hydride abstraction of the bis(dimethylsilyl)amido moiety, to afford heteroleptic cerium(IV) species containing a dimethylpyrazolyl-substituted silylamido ligand, namely [Ce(Me 2 pz) 3 (bpsa)] (bpsa = bis((3,5-dimethylpyrazol-1-yl)dimethylsilyl)amido)), along with other cerium(III) species. Remarkably, the nucleophilic attack of the pyrazolyl at the silicon atom and concomitant Si-H-bond cleavage is restricted to the tetravalent cerium oxidation state and appears to proceed via the formation of a transient cerium(IV) hydride, which engages in immediate redox chemistry. When [Ce(Me 2 pz) 4 ] 2  is treated with [Li{N(SiMe 3 ) 2 }], that is, in the absence of the SiH functionality, any redox chemistry did not occur. Instead, the ceric ate complex [LiCe 2 (Me 2 pz) 9 ] and the stable mixed-ligand ceric species [Ce(Me 2 pz) 2 {N(SiMe 3 ) 2 } 2 ] were obtained. PMID: 32239686 [PubMed - as supplied by publisher]
Source: Chemistry - Category: Chemistry Authors: Tags: Chemistry Source Type: research

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AbstractThe diagnosis of mange is problematic in the absence of mites in skin scrapings because many skin diseases present similar gross features as mange. The study evaluated the stepwise procedure for herd diagnosis of mange in the West African Dwarf (WAD) and Red Sokoto (RS) goats with greater specificity and sensitivity. Twenty-seven WAD goats (n = 27) and forty RS goats (n = 40) goats with mange-like skin lesions (alopecia, scabs, crusts, and scratch injuries) out of a total herd population of 114 WAD goats and 317 RS goats respectively in Nsukka, Eastern Nigeria, were examined by directed ...
Source: Comparative Clinical Pathology - Category: Pathology Source Type: research
Publication date: Available online 23 May 2020Source: Aquatic ToxicologyAuthor(s): Robert J. Lennox, Anne Gro Vea Salvanes, Bjørn T. Barlaup, Elisabeth Stöger, Abdullah Madhun, Turid M. Helle, Knut Wiik Vollset
Source: Aquatic Toxicology - Category: Toxicology Source Type: research
AbstractPurpose of ReviewHead lice infestations remain an important public health problem, albeit poorly defined in most endemic countries. Reports of increasing resistance to first-line treatment have renewed scientific research into this neglected ectoparasitosis. Mapping and understanding resistance mechanisms are essential for the development of more effective treatments, as well as for prolonging the life of existing pediculicides. This review aims to synthetize recent data on the type, frequency, and distribution of genetic mutations associated with head lice resistance to chemical treatments.Recent FindingsHead lice...
Source: Current Tropical Medicine Reports - Category: Tropical Medicine Source Type: research
Publication date: Available online 11 May 2020Source: EpidemicsAuthor(s): Adel Elghafghuf, Raphael Vanderstichel, Larry Hammell, Henrik Stryhn
Source: Epidemics - Category: Epidemiology Source Type: research
ConclusionThis literature review summarized the physical illnesses prevalent among homeless children and the contributing factors leading to them. Gaps in the literature were also identified and included a dearth of studies focusing on younger children compared with adolescents.Further research into prevention and intervention programs for this vulnerable population is urgently needed.
Source: Irish Journal of Medical Science - Category: General Medicine Source Type: research
Benzyl alcohol (BnOH), an aromatic alcohol produced by plants, is frequently used as a bacteriostatic preservative at 5% concentration in the treatment of head lice [1]. It is also used as an alternative local anesthetic [2] and attenuates acetaminophen-induced acute liver injury [3]. Research on the use of BnOH in wound healing is scarce, although its derivatives are widely used in wound healing. Benzoyl alcohol together with glycyl-1-histidyl-1-lysine copper complex was shown to increase wound healing and skin re-epithelialization, although benzoyl alcohol was known to inhibit the function of wound fibroblasts.
Source: Injury - Category: Orthopaedics Authors: Source Type: research
In this study, we focus on the essential oils derived from 22 plant genera, their constituents, and the major factors that play important roles in the effectiveness of these oils in the treatment of pediculosis. Furthermore, we discuss the advantages and limitations of the mentioned essential oils, and ultimately suggest those demonstrating the most effective in vitro pediculicidal activities. The genera such as Aloysia, Cinnamomum, Eucalyptus, Eugenia, Lavandula, Melaleuca, Mentha, Myrcianthes, Origanum, Pimpinella, and Thymus appear to be more efficient against lice. These genera are rich in anethole, 1,8-cineole, c...
Source: Planta Medica - Category: Drugs & Pharmacology Authors: Tags: Reviews Source Type: research
Vector-Borne and Zoonotic Diseases, Ahead of Print.
Source: Vector-Borne and Zoonotic Diseases - Category: Infectious Diseases Authors: Source Type: research
t AL Abstract Anti-sea lice pesticides, used in the salmonid aquaculture industry, are a growing environmental concern due to their potential to adversely affect non-target crustaceans. Azamethiphos and deltamethrin are two bath treatment pesticides used on salmon farms in Norway, however, limited information is available on their impact on European lobster (Homarus gammarus) larvae in the Norwegian marine environment. Here, we firstly report the lethal (LC50) and effective (EC50) concentrations of azamethiphos and deltamethrin for stage I and stage II larvae, following 1-h exposures. Using a hydrodynamic model, w...
Source: Environmental Pollution - Category: Environmental Health Authors: Tags: Environ Pollut Source Type: research
Authors: Radad K, Al-Shraim M, Al-Emam A, Wang F, Kranner B, Rausch WD, Moldzio R Abstract Rotenone ([2R-(2α,6aα,12aα)]-1,2,12,12a-tetrahydro-8,9-dimethoxy-2-(1-methylethenyl)-[1]benzopyran[3,4-b]furo [2,3-h][1]benzopyran-6(6aH)-one) is a naturally occurring compound derived from the roots and stems of Derris, Tephrosia, Lonchocarpus and Mundulea plant species. Since its discovery at the end of the 19th century, rotenone has been widely used as a pesticide for controlling insects, ticks and lice, and as a piscicide for management of nuisance fish in lakes and reservoirs. In 2000, Betarbet et al. r...
Source: Folia Neuropathologica - Category: Neurology Tags: Folia Neuropathol Source Type: research
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