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Mária Bobošíková, František Mathia, Daniel Végh, Štefan Marchalín and Michaela Halinkovičová

Abstract

The review is an attempt at critical evaluation of known synthetic procedures used for laboratory and industrial preparation of a synthetic antihypertensive - Dexmedetomidine as to their complexity, published yield and atom economy

Open access

Vrábel Viktor, Sivý Július, Šafař Peter and Marchalín Štefan

Abstract

The title compound, C11H16NOS・I, is chiral molecule with three stereogenic centres. The absolute configuration was assigned from the synthesis and confirmed by the structure determination. The central six-membered ring of the indolizine moiety adopts a half-chair conformation with atom displaced by 0.655 (2) A from the plane of the oder remaining five atoms. The pyrrolidine ring adopts an envelope conformation, with the greatest deviation from the mean plane of the ring being 0.646 (2) A for the bridgehead N atom. The crystal structure of the title compound is stabilized by O-H・・・I and C-H・・・O hydrogen bonds.

Open access

Viktor Vrábel, Július Sivý, Peter Šafař and Štefan Marchalín

Abstract

The title compound, C13H15NO3S, is a chiral molecule with two stereogenic centres. Its absolute configuration was derrived from the synthesis and confirmed by structure determination. The expected stereochemistry of atoms C5 and C6 was confirmed to be S. The central N-heterocyclic rings are not planar and adopt a half-chair conformation. A calculation of least-squares planes showed that these rings are puckered in such a manner that the five atoms C1, C2, C3, C5 and N1 (second ring: N1, C6, C7, C10 and C11) are planar, while atoms C4 (C5) are displaced from these planes with the out-of-plane displacement of 0.582 (3) Å and 0,666 (2) Å in the second ring, respectively. Dihedral angle between the planes of the central N-heterocyclic rings is 40.0 (1)°. Crystal structure is stabilized by C—H···O hydrogen interactions.

Open access

František Mathia, Štefan Marchalín, Daniel Végh, Mária Bobošíková and Michaela Halinkovičová

Abstract

The submitted review aims at critical evaluation of known synthetic procedures utilized both for laboratory and industrial production of the synthetic analgesic - remifentanil as to their simplicity, published yield and atom economy.

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.