Experimental (IR and Raman) and theoretical (Kohn-Sham calculations) methods are used in a combined analysis aimed at refining the available structural data concerning the molecular guests in channels formed by stacked dibenzo-18-crown-6 (DB18C6) crown ether. The calculations are performed for a simplified model comprising isolated DB18C6 unit and its complexes with either H2O or H3O+ guests, w...

From extraction experiments and gamma-activity measurements, the extraction constan corresponding to the equilibrium NH4(+)(aq) + 1*Na(+)(nb) <=> 1*NH4(+)(nb) + Na(+)(aq) taking place in the two-phase water - nitrobenzene system (1 = dibenzo-18-crown-6, aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log K(ex) (NH4(+),1*Na(+)) = -0.1 +/- 0.1. Further, the stability constant of the...

Purpose of review At the time of diagnosis of the trisomy 18 and trisomy 13, parents and care providers face difficult and challenging decisions regarding management. Because of the increased infant mortality and developmental outcome associated with both conditions, the conventional approach to management has been to withhold technological support. In recent years, an active dialogue on this t...

Hsp70 chaperones mediate folding of proteins and prevent their misfolding and aggregation. We report here on a new kind of Hsp70 interacting protein in mitochondria, Hep1. Hep1 is a highly conserved protein present in virtually all eukaryotes. Deletion of HEP1 results in a severe growth defect. Cells lacking Hep1 are deficient in processes that need the function of mitochondrial Hsp70s, such as...

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The reaction of 4-bromo-aniline, 18-crown-6, and perchloric acid in methanol yields the title compound, C(6)H(7)BrN(+)·ClO(4) (-)·C(12)H(24)O(6), in which the protonated -NH(3) (+) group forms three bifurcated N-H⋯O hydrogen bonds to the O atoms of the crown ether.

It is a pleasure to be able to introduce this second Thematic Series on ‘organo-fluorine chemistry’ within the Beilstein Journal of Organic Chemistry. The series now embeds the subject firmly as a special interest area of the journal. The first series in 2008 presented contributions representing a wide range of organic fluorine chemistry [1-10] and this series continues that trend exploring the...