Biomedical subjects

Maria Gdaniec

Publications and source records attributed to Maria Gdaniec.

25 records · Page 2Linked to original sources

PubMed2003

Synthesis and anticancer activity of 2-amino-8-chloro-5,5-dioxo[1,2,4]triazolo[2,3-b][1,4,2]benzodithiazine derivatives.

A new series of 1-(6-chloro-1,1-dioxo-1,4,2-benzodithiazin-3-yl)-4-arylsemicarbazides (4-16) were obtained. Intramolecular ring closure in semicarbazides 4-16 upon treatment with phosphorus oxychloride resulted in the formation of 2-amino-8-chloro-5,5-dioxo[1,2,4]triazolo[2,3-b][1,4,2]benzodithiazines 17-29 with potential antitumor activity. The structures of these compounds were confirmed on the basis of elemental analysis, spectral data and X-ray analysis. Compounds 17-29 were screened at the US National Cancer Institute (NCI) for their activities against a panel of 59 tumor cell lines, and relationships between structure and antitumor activity in vitro are discussed. The benzodithiazines 18, 19, 23, 28 and 29 were inactive, whereas the other compounds exhibited reasonable activity against numerous human tumor cell lines. The prominent compound 17 showed significant activity against the leukemia SR cell line (log GI(50)=-7.67, log TGI=-6.90 and log LC(50)=-4.77).

Antineoplastic Agents↗

PubMed2003

Synthesis and structure of novel 2,3, 5,6-tetrahydro-1H-imidazo[2,1-b][1,3,5]benzotriazepines with vasocontractile activity in rabbit aortic rings.

A series of novel 2,3,5,6-tetrahydro-1H-imidazo[2,1-b][1,3,5]benzotriazepines (3a-n) and hydrochlorides (4a-b) were prepared and their structure was determined by IR and NMR spectroscopic data as well as by X-ray analysis of the hydrochloride 4a. The newly synthesized benzotriazepine 4b exhibited concentration-dependent vasocontractile activity in isolated rabbit aortic rings. Rimalkalim was found to induce a relaxation in rabbit aortic rings precontracted by 4b (3x10(-5) mol). Present results indicate that K(ATP)-dependant channels may contribute in the contractile activity of benzotriazepine 4b.

Animals↗

PubMed2002

Hydrogen-bonded one-dimensional networks in 1:1 complexes of N,N'-bis(2-pyridyl)aryldiamines with anilic acid.

The 1:1 complexes N,N'-bis(2-pyridyl)benzene-1,4-diamine-anilic acid (2,5-dihydroxy-1,4-benzoquinone) (1/1), C(16)H(14)N(4).C(6)H(4)O(4), (I), and N,N'-bis(2-pyridyl)biphenyl-4,4'-diamine-anilic acid (1/1), C(22)H(18)N(4).C(6)H(4)O(4), (II), have been prepared and their solid-state structures investigated. The component molecules of these complexes are connected via conventional N-H.O and O-H.N hydrogen bonds, leading to the formation of an infinite one-dimensional network generated by the cyclic motif R(2)(2)(9). The anilic acid molecules in both crystal structures lie around inversion centres and the observed bond lengths are typical for the neutral molecule. Nevertheless, the pyridine C-N-C angles [120.9 (2) and 120.13 (17) degrees for complexes (I) and (II), respectively] point to a partial H-atom transfer from anilic aicd to the bispyridylamine, and hence to H-atom disorder in the OHN bridge. The bispyridylamine molecules of (I) and (II) also lie around inversion centres and exhibit disorder of their central phenyl rings over two positions.

Journal Article↗

PubMed2002

(S)-trans-cyclohexane-1,2-dicarboximide.

The molecule of the title compound, C(8)H(11)NO(2), contains a strained bicyclic system with a significantly twisted imide chromophore. The five-membered ring fragment containing the imide function is strongly puckered and adopts a half-chair conformation. The six-membered ring has a slightly distorted chair conformation. The molecules are joined by strong N-H.O and weak C-H.O hydrogen bonds into infinite chains.

Journal Article↗

PubMed2002

The beta-polymorph of phenazine.

In beta-phenazine, C(12)H(9)N(2), the molecules show a sandwich herring-bone type of packing. The experimental crystal structure shows very good agreement with that predicted earlier from systematic searches of potential packing arrangements for the known unit cell [Hammond, Roberts, Smith & Docherty (1999). J. Phys. Chem. B, 103, 7762-7770].

Journal Article↗

PubMed1996

Structure, Conformation, and Stereodynamics of N-Nitroso-2,4-diaryl-3-azabicyclo[3.3.1]nonanes and N-Nitroso-2,4-diaryl-3-azabicyclo[3.3.1]nonan-9-ones(1).

The variable temperature (1)H, (13)C, and (19)F NMR spectra were measured for the title N-nitrosamines. The observed unusually low N-N rotation barriers (12-15 kcal/mol) result from a significant deviation of the nitrosamino system from planarity. A pyramidal character of the amino nitrogen was confirmed by the X-ray crystal structures of two compounds and by bathochromic shifts of the n-pi absorption bands in the UV spectra. The nonplanarity of the nitrosamino moiety is due to the strong pseudoallylic A((1,3)) strain caused by the steric interaction of the NNO group with the neighboring aryl substituents fixed in the equatorial positions of the bicyclic skeleton. In addition, the barriers to the C-C rotation of aryl groups were examined at temperatures lower than required to "freeze" the N-N rotation and different DeltaG() values were observed for the aryls oriented syn and anti to the nitroso oxygen.

Journal Article↗

PubMedDate not supplied

Synthesis, structural characterization and in vitro antitumor activity of 4-dimethylaminopyridinium (6-chloro-1,1-dioxo-1,4,2-benzodithiazin-3-yl)methanides.

Previously, we have described a novel series of low molecular weight cancer-specific antitumor agents with aminium N-(1,1-dioxo-1,4,2-benzodithiazin-3-yl)arylsulfonamidate structure. In an attempt to determine some of the structural features that account for the cytotoxic activity of such aminium salts, a novel series of 4-dimethylaminopyridinium (1,1-dioxo-1,4,2-benzodithiazin-3-yl)methanides (6-19) has been synthesized by the reactions of 3-methylthio-1,4,2-benzodithiazine1,1-dioxides with 4-DMAP and some active methylene compounds. The in vitro antitumor activity of these compounds has been tested in the National Cancer Institute (NCI), and relationships between structure and antitumor activity are discussed. Among the aminium salts 4-dimethylamino-pyridinium 4-chlorobenzoyl cyano (6-chloro-7-methyl-1,1-dioxo-1,4,2-benzodithiazin-3-yl)methanide (9) was superior to other pyridinium salts in terms of both remarkable activity (log GI50 and logTGI<-8.00) and high selectivity for the lung HOP-92 and melanoma UACC-257 cell lines.

4-Aminopyridine↗