Background: In the coming years, telemedicine will play a key role in health care. Especially in rural areas with weak infrastructure, telemedicine could be crucial to providing adequate and personalized medical care.
Objective: We investigated the acceptance and preferences of telemedicine among cardiologists, internists, and general practitioners.
We report a concise approach to phenanthroindolizidine alkaloids, wherein strained azacyclic alkynes are intercepted in Pd-catalyzed annulations. Two types of strained intermediates were evaluated: a functionalized piperidyne and a new strained intermediate, an indolizidyne. We show that each can be employed, ultimately allowing access to three natural products: tylophorine, tylocrebine, and isotylocrebine.
View Article and Find Full Text PDFPhosphorus (P) fertilizers from secondary resources became increasingly important in the last years. However, these novel P-fertilizers can also contain toxic pollutants such as chromium in its hexavalent state (Cr(VI)). This hazardous form of chromium is therefore regulated with low limit values for agricultural products even though the correct determination of Cr(VI) in these fertilizers may be hampered by redox processes, leading to false results.
View Article and Find Full Text PDFPhosphorus (P) is an essential element for all forms of life and is thus often applied as phosphate rock-based P-fertilizers in agriculture to enable continuous farming. However, these P-fertilizers contain also hazardous uranium (U) and thorium (Th), up to 660 and 220 mg/kg, respectively. On the contrary, novel P-fertilizers made from sewage sludge (ash) contain only low mass fractions of U and Th.
View Article and Find Full Text PDFExperimental and computational studies pertaining to the Fischer azaindolization reaction are reported. These studies explain why pyridylhydrazines are poorly reactive in Fischer indolization reactions, in addition to the origin of hydrazine substituent effects. Additionally, an interrupted variant of Fischer azaindolization methodology is disclosed, which provides a synthetic entryway into fused azaindoline scaffolds.
View Article and Find Full Text PDFThe nickel-catalyzed reduction of secondary and tertiary amides to give amine products is reported. The transformation is tolerant of extensive variation with respect to the amide substrate, proceeds in the presence of esters and epimerizable stereocenters, and can be used to achieve the reduction of lactams. Moreover, this methodology provides a simple tactic for accessing medicinally relevant α-deuterated amines.
View Article and Find Full Text PDFGold(I)-polyoxometalate hybrid complexes 1-4 ([PPh3AuMeCN]xH4-x SiW12O40, x=1-4) were synthesized and characterized. The structure of the primary gold(I)-polyoxometalate 1 (x=1) was fully ascertained by XRD, FTIR, (31)P and (29)Si magic-angle spinning (MAS) NMR, mass spectroscopy, and SEM-energy dispersive X-ray spectroscopy (EDX) techniques. Moreover, this complex exhibited better catalytic activity and selectivity compared with standard, homogeneous, gold catalysts in the new rearrangement of propargylic gem-diesters.
View Article and Find Full Text PDFMultifaceted gold(I/III) catalysts with their carbophilic and oxophilic characters catalyzed very efficiently the formation of hydroxylated cyclopentenones from simple divinyl ketones or acyloxyalkynyloxiranes. The Nazarov reaction is rapidly performed in dichloroethane with 5 mol % of the simple gold(III) trichloride salt at 70 °C, while the rearrangement of alkynyloxiranes requires 5 mol % of a more stable NHC gold(III) triflimidate complex.
View Article and Find Full Text PDFBeilstein J Org Chem
September 2013
Various γ-acyloxyalkynyl ketones were efficiently converted into highly substituted furans with 2.5 mol % of triflimide (triphenylphosphine)gold(I) as a catalyst in dichloroethane at 70 °C.
View Article and Find Full Text PDFVarious N-aryl-2-alkynylazetidines were very efficiently converted to pyrrolo[1,2-a]indoles with gold catalysts, especially the 2-biphenyl-dicyclohexylphosphino-gold(I) hexafluoroantimonate, in dichloromethane at room temperature. Additionally, two formal syntheses of bioactive non-natural compounds, i.e.
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