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It is stated that gel permeation chromatography was applied to iodine scavenging studies of the distribution of radicals produced in the radiolysis of symmetrically branched hydrocarbons 2,3-dimethylbutane, 2,4-dimethylpentane, and 3-ethylpentane. The report stated that in all the three cases the rupture of terminal C-C bonds is relatively infrequent with C-C rupture occurring preferentially at the bonds adjacent to the tertiary carbon.

The crystal and molecular structures of three new phosphorochromones determined by the X-ray diffraction method are presented. The results on model system stated that bifurcated H bonds were weak and the binding energies were equal to 2.9-3.5 kcal/mol.

A reply on the comment forwarded on rationalizing the strength of hydrogen-bonded complexes. Ab initio HF and DFT studies is presented. Clarification and explanation are forwarded in this study to verify the applicability of empirical rules.

A comment is presented to correct an analysis of data in the Ph.D. thesis of G.C. Alexander reported by Glebov et al. The comment is also forwarded with detailed study and observation to improve the understanding of the kinetics reaction in the model.

A report is presented that addresses the important question of whether the stability of the hydrogen-bond complexes with amide-type donors and acceptors in solution can be predicted by empirical parameters derived from experimental studies and whether ab initio calculations perform significantly. Clarification and explations are forwarded to clarify the comment.

The article focuses on the crystallization of the compound (E)-3-{[(Dimethoxythiophosphoryl)methyl-hydrazono]methyl}-4H-1-benzopyran-4-one. It is a new chromone derivative substituted with phosphorohydrazide at position 3. The molecule of the compound consists of a benzopyran moiety and has two planar groups, benzopyran and methylhydrazone. The compound was formed by the reaction of equimolar amounts of 4-oxo-4H-benzopyran-3-carbaldehyde and N' -dimethoxyphosphonate- N' -methylhydrazide in methanol.

The effect of ten phosphorohydrazone derivatives of chromone on the fibrin formation process was evaluated in the presence of basic fibroblast growth factor (bFGF), which plays an important role in tumor angiogenesis. The relationship between the chemical properties of the derivatives and the resulting fibrin structure was also examined. The structure of fibrin was analyzed by UV spectrophotometry and the degree of bFGF binding to fibrin was estimated by Western blotting. The measurements were taken at 3 different pH values: 6.64, 7.60 and 8.40. Three of the analyzed phosphorohydrazone derivatives (compounds 2, 7 and 10) demonstrated the most significant influence on reduction of polymerization at the studied pH values.

Novel palladium(II) complexes (4-6) have been synthesized from the reaction of (E)-3{[(diethoxythiophosphoryl)-methylhydrazone]-methylene}-4-hydroxy-2H-1-benzopyran-2-one (1), E)-3-{[(dimethoxythiophosphoryl)-methylhydrazine]-methylidene}-3,4-dihydro-2H-1- benzopyran-2,4-dione (2) and (E)-3-{[(diethoxythiophosphoryl)-hydrazone]-methylene}- 4H-1-benzopyran-4-one (3), respectively, with PdCl2(PhCN)2. These complexes have been characterized by elemental analysis and spectroscopic studies. The alkylating activity of the complexes was examined in vitro toward 4-(4'-nitrobenzyl)pyridine (NBP test). The palladium(lI) complexes were found to possess alkylating activity. The compounds (4-6) have been screened for their antibacterial properties and displayed low activity.