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Viktor Vrábel, Július Sivý, Ľubomír Švorc, Jan Světlík and Šafař Peter

Abstract

We report here the structure of new spiro-derivative, namely methyl (2R,4R)-4-(5-methylthiazol- 2-ylamino)spiro[chroman-2,2’-chromene]-3’-carboxylate, C23H20N2O4S, which crystallizes as racemate in the space group P-1. In this compound, the chromanone moiety consists of a benzene ring fused with a sixmembered heterocyclic ring which adopts a distorted half-chair conformation. The molecules are linked by a combination of N–H⋯N hydrogen bonds and weak C–H⋯O, C-H⋯S, C-H⋯π, inter- and intramolecular interactions resulting in a two-dimensional network in the crystal structure.

Open access

Viktor Vrábel, Július Sivý, Ľubomír Švorc, Jan Světlík and Štefan Marchalín

Abstract

We report here the crystal and electronic structure of a new spiro-derivative, namely methyl (2R,4S)- 4-(benzothiazol-2-ylamino)-8,8´-dimethoxyspiro[chroman-2,2´-chromene]-3´-carboxylate (I), C28H24N2O6S, which crystallizes as racemate in the space group C2/c. In this compound, the chromanone moiety consists of a benzene ring fused with a six-membered heterocyclic ring which adopts a distorted half-chair conformation. The molecules are linked by a combination of N-H∙∙∙N hydrogen bonds and weak C-H∙∙∙O, C-H∙∙∙S, C-H∙∙∙ π, inter- and intra-molecular interactions resulting in a two-dimensional network in the crystal structure.

Open access

Viktor Vrábel, Július Sivýb, Jan Světlíkc, Štefan Marchalínd and Šafař Peterd

Abstract

We report here the crystal and molecular structure of a new chromane-derivative, namely isopropyl( 2R*,3S*,4S*)-4-(benzo[d]thiazol-2-ylamino)-2-hydroxy-2-ethylchromane-3-carboxylate (I), C21H22N2O4S, which crystallizes as racemate in the space group C2/c. Its structure has been solved using X-ray diffraction data obtained at low temperature (100(2) K). In this compound, the chromane moiety consists of a benzene ring fused with a six-membered heterocyclic ring which adopts a distorted half-chair conformation. The molecules are linked by a combination of O-H∙∙∙N and N-H∙∙∙O hydrogen bonds, resulting in a twodimensional network which helps stabilizing the crystal structure of the compound (I). Dihedral angle between the chromane and benzothiazol rings is 80.6(1)0.

Open access

Juraj Jagelcak, Jan Vrabel and Michael Nieuwesteeg

Abstract

Since 2014, work regarding the revision of the Standard EN 12642 “Securing of cargo on road vehicles - Body structure of commercial vehicles - Minimum requirements” has been done, which is known for users of CODE XL certified swap bodies. Based on the negotiations on the above-mentioned standard, requirements for the revision of other standards for the cargo securing emerged. Currently, Expert group CEN TC 119 WG 7 is working on these standards. This paper discusses about the standards revision regarding the cargo securing.

Open access

Jacek Caban, Eva Brumercikova, Bibiana Bukova, Frantisek Brumercik, Ján Vrábel, Branislav Šarkan and Piotr Ignaciuk

Abstract

The maritime transport is particularly exposed to danger due to the environment of its operations. These are the threat dependent and independent of human e.g. environmental, safety health and life of humans or belongings. In spite of attempts to limit the risk of danger, it is impossible to completely eliminate it. The article presents some aspects of the state of transportation safety in the Baltic Sea from Statistical Yearbook of Maritime Economy and Helcom as well as attempt the undertaken to analyses the security state of this sea area in 2009 to 2015.