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The novel hydroxyurea 5 derivative of L-valine was prepared by aminolysis of N-(1-benzotriazolecarbonyl)- L-valine cyclohexanemethylamide 4 with hydroxylamine. The corresponding hydantoin derivative 6 was synthesized by base catalyzed cyclization of the amide 4. The exact stereostructure of hydantoin derivative 6 has been determined by X-ray crystal structure analysis. The chiral atom of the hydantoin ring in 6 has S configuration what is in agreement with its configuration in the starting L-valine. The molecules of 6 are joined into infinite chains by N–H⋯O intermolecular hydrogen bond. The infinite chains are additionally linked by two C–H⋯O hydrogen bonds, thus forming two-dimensional network. The hydantoin derivative of L-valine 6 and its L-leucine analogue LH have similar packing arrangements, so they are homostructural. [ABSTRACT FROM AUTHOR]

The novel purine and pyrimidine derivatives of 1-aminocyclopropane-1-carboxylic acid 1 and 2 were obtained by alkylation of 6-( N-pyrrolyl)purine and thymine with methyl 1-benzamido-2-chloromethylcyclopropanecarboxylate. X-ray crystal structure analysis shows that the cyclopropane rings in 1 and 2 posses Z-configuration. The cyclopropane ring atoms and attached atoms of the benzamido and methoxycarbonyl moiety of both molecules are disposed perpendicularly to each other. The carbonyl oxygen of the methoxycarbonyl moiety adopts in both compounds a synperiplanar conformation with respect to the midpoint of the distal bond of the cyclopropane ring. The torsion angles φ and ψ for the 1-aminocyclopropane-1-carboxylic acid residue in 1 and 2 correspond to a folded conformation, while the torsion angles ω define antiperiplanar conformation. Intermolecular hydrogen bonds connect the molecules of 1 into dimers. Each dimer is hydrogen-bonded with four ethanol molecules, thus forming discrete unit. On the contrary, intermolecular hydrogen bonds link the molecules of 2 generating three-dimensional network. [ABSTRACT FROM AUTHOR]

The effect of ortho substituents NH2, OCH3, CH3, Cl and NO2 on the fragmentation of five symmetrically and five unsymmetrically 2,2′-disubstituted stilbenes under electron impact was investigated. The fragmentation patterns deduced were supported by metastable transitions in the first and second field free regions and by exact mass measurements of prominent ions. In general, the fragmentation was found to be in accord with that of stilbene and the corresponding monosubstituted stilbenes. There are, however, some deviations from the general fragmentation scheme caused by direct through-space interactions of the ortho, ortho′ substituents with concomitant loss of neutral fragments. It is supposed that the formation of 7-membered cyclic or heterocyclic ions is the result of such through-space reactions. [ABSTRACT FROM AUTHOR]

The electron impact induced fragmentations of the C-5 unsubstituted and 5-methyl N-aryl-4 H-5,7a-epoxyisoindolines (where aryl is pheny, p-tolyl, p-methoxyphenyl, o-methoxyphenyl and p-chlorophenyl) were investigated. The fragmentation patterns deduced were supported by exact mass measurements of prominent ions and by deuterium labelling. The retro Diels-Alder fragmentation turned out to be a predominant process in all the compounds investigated. In the mass spectra of the 5-methyl N-aryl-4 H-5,7a-epoxyisoindolines hydrogen migration preceding fragmentation occurred. From the mass spectrum of the specifically deuterated compound it was concluded that the transferred hydrogen originates exclusively from the 5-methyl group. [ABSTRACT FROM AUTHOR]

Non-steroidal anti-inflammatory drugs (NSAID) pharmacophores are interesting in designing potential anticancer drugs. Indeed, numerous experimental, epidemiologic and clinical studies suggest that NSAIDs are promising anticancer drugs. Herein, NSAID hydroxamic acids 3a-i were prepared by a new synthetic procedure and evaluated for their antiviral and cytostatic activity against malignant tumor cell lines and normal human fibroblasts (WI38). Antiviral activity evaluation results indicated that 3f had only a minor activity against the influenza virus A/H1N1 subtype with a selectivity index of 7-10. On the other hand, the results of the in vitro cytostatic activity evaluations revealed that the majority of NSAID hydroxamic acid derivatives 3a-i exhibited a strong non-specific antiproliferative effect at the highest concentration (100 microM) on the tested cell line panel. Only compounds 3b, 3e and 3i exerted a differential dose-dependent inhibitory activity against the growth of HeLa cells (p < 0.05) at concentration 10 microM. Among those three compounds, only compound 3b showed a selective cytostatic effect on HeLa in comparison with normal fibroblasts.

The novel hydroxyurea derivatives of l- and d-amino acid amides 5a-l were prepared by aminolysis of N-(1-benzotriazolecarbonyl)-amino acid amides 4a-f with O-benzylhydroxylamine and N-methylhydroxylamine and evaluated for their antiviral and cytostatic activity against malignant tumor cell lines and normal human fibroblasts. Compounds 5a, 5c, 5e and 5k showed the highest antiproliferative effects against all tumor cell lines tested. The strongest non-specific cytostatic activities against HeLa cells were affected by compounds 5a, 5c, 5e and 5k on MCF-7 cells by 5c, 5e and 5k and MIA PACa-2 cells by 5c and 5k. Differential effects at micromolar concentrations were observed for compounds 5a, 5c, 5e, 5k and 5l in Hep G2 cells, for compounds 5c, 5e, 5k and 5l in PC-3 cells and for compounds 5e, 5k and 5l in SW 620 cells.

In the title compound, C10H14N2O3, a pyrimidine ring is fused with a piperidine ring. The pyrimidine ring is planar, whereas the piperidine ring adopts a half-chair conformation. The molecules of the title compound are connected via O-H...O intermolecular hydrogen bonds into infinite zigzag chains. The pyrimidine ring is involved in three C-H...pi interactions, which link the hydrogen-bonded chains into a three-dimensional framework.