Hyperthermic sensitivity, kinetics of thermotolerance induction and decay, and profile of heat shock protein synthesis were studied in human granulocyte-macrophage progenitors and nucleated bone marrow cells, respectively. The I),, of the heat survival curves of human granulocytemacrophage colony-forming cells at 43°C,44°C,and 45°Cwere 23, 12, and 5 min, respectively. The kinetics of thermot...

In biomolecules, bifurcated H-bonds typically involve the interaction of two donor protons with the two lone pairs of oxygen. Here, we present direct NMR evidence for a bifurcated H-bonding arrangement involving nitrogen as the acceptor atom. Specifically, the H-bond network comprises the Nδ1 atom of histidine and both the backbone N-H and side-chain Oγ-H of threonine within the conserved TXXH ...

In the title coumarin derivative, C(13)H(12)O(4), the 2H-chromene ring system is essentially planar [maximum deviation = 0.047 (1) Å]. An intra-molecular hydrogen bond is observed between the hy-droxy and the ketonic O atoms. In the crystal, pairs of inter-molecular C-H⋯O hydrogen bonds link inversion-related mol-ecules into dimers. Additional inter-molecular C-H⋯O hydrogen bonds further inter-...

In the crystal of the title compound, C(8)H(8)N(4) (2+)·2I(3) (-)·2C(8)H(6)N(4)·2H(2)O, inversion centres are located at the centroids of the central C-C bonds of the cation and the bpym mol-ecules, as well as at the central I atoms of both anions. Inter-molecular O-H⋯N and N-H⋯O hydrogen bonds are observed in the crystal structure.

The complete anion of the title hydrated mol-ecular salt, 2C(5)H(8)N(3) (+)·C(8)H(4)O(4) (-)·2H(2)O, is generated by a crystallographic twofold axis. In the crystal, the cations, anions and water mol-ecules are connected by N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds, forming a three-dimensional network. The crystal structure also features C-H⋯π inter-actions.

Nucleophilic substitution reactions of 2-halo-2H-azirines 1a, 1b, 1d, and 1e with potassium phthalimide and aniline allowed the preparation of new substituted 2H-azirines 2-5. The reactions of 2-bromo-2H-azirine 1a with methylamine led to the synthesis of alpha-diimines 7 and 8. 2-Halo-2H-azirines were also established as building blocks for the synthesis of a range of heterocyclic compounds, n...

Let c be a square-free positive integer and p prime satisfying $$p\not \mid c$$ . $$h(-c)$$ denote the class number of imaginary quadratic field $$\mathbb {Q}(\sqrt{-c})$$ In this paper, we consider Diophantine equation $$\begin{aligned}&cx^2+p^{2m}=4y^n,~~x,y\ge 1, m\ge 0, n\ge 3,\\&\quad \gcd (x,y)=1, (n,2h(-c))=1, \end{aligned}$$ describe all its solutions. Our main tool here is prominent re...

A procedure has been developed for synthesis of 2-alkenyl-2H-indazoles starting from 2-(2-carbonylmethyl)-2H-indazoles, which are prepared by gallium/aluminium- and aluminium-mediated, direct, regioselective alkylation of indazoles with α-bromocarbonyl compounds. The structure of 3-(2H-indazol-2-yl)-2H-chromen-2-one was proven by X-ray crystallography. The styrene- and coumarin-2H-indazoles pro...

   The study aimed at the synthesis and antibacterial activity of ZnO nanoparticles (NPs) from organic extracts of Cola nitida and Cola acuminata leaf using zinc chloride (ZnCl2) and zinc acetate dihydrate [Zn(CH3COO)2∙2H2O] as precursors on selected Gram positive and Gram negative microbes: Staphylococcus aureus, Exiguobacterium aquaticu...