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Tadeusz Lis

Publications and source records attributed to Tadeusz Lis.

At least 19 recordsLinked to original sources
PubMed2006

A chloro-bridged dinuclear phosphinitopalladium complex, di-mu-chloro-bis[(diphenoxyphosphinite-kappaP)(diphenoxyphosphinito-kappaP)palladium(II)].

The title compound, [Pd2(C12H10O3P)2Cl2(C12H11O3P)2], consists of a dinuclear mu-chloro-bridged palladium unit with two diphenoxyphosphinite groups per Pd atom, linked together by a hydrogen bond. The asymmetric unit contains one half of the molecule, with the other half generated by an inversion centre. The geometry around the P atoms may be described as distorted tetrahedral. Adjacent molecules of the complex are linked by weak C-H...O and C-H...Cl hydrogen bonds. The structure is additionally stabilized by pi-pi stacking interactions between the aryl rings. These interactions form a herring-bone pattern in the crystal structure.

Journal Article↗
PubMed2006

Supercell and subcell description of the crystal structure of triammonium bis(O-phospho-L-serinate) trihydrate.

The X-ray diffraction pattern obtained for a crystal of triammonium bis(O-phospho-L-serinate) trihydrate at 100 K displays the presence of weak superstructure reflections with odd l indices. Omission of the superstructure reflections leads to orthorhombic Laue symmetry. The structure may be solved and refined in the space group P2(1)2(1)2(1) as an average structure omitting the weak reflections. The model reveals the presence of O-phospho-L-serinate monoanions, ammonium cations and partly disordered water molecules. The structure solution for the whole data set could be obtained only in the space group P2(1). There are two monoanions and two dianions of O-phospho-L-serinate per asymmetric unit, as well as six ordered ammonium cations and six water molecules.

Chemical Phenomena↗
PubMed2006

Different nucleobase orientations in two cyclic 2',3'-phosphates of purine ribonucleosides: Et(3)NH(2',3'-cAMP) and Et(3)NH(2',3'-cGMP)xH(2)O.

The crystal structures of triethylammonium adenosine cyclic 2',3'-phosphate {systematic name: triethylammonium 4-(6-aminopurin-9-yl)-6-hydroxymethyl-2-oxido-2-oxoperhydrofurano[3,4-c][1,3,2]dioxaphosphole}, Et(3)NH(2',3'-cAMP) or C(6)H(16)N(+).C(10)H(11)N(5)O(6)P(-), (I), and guanosine cyclic 2',3'-phosphate monohydrate {systematic name: triethylammonium 6-hydroxymethyl-2-oxido-2-oxo-4-(6-oxo-1,6-dihydropurin-9-yl)perhydrofurano[3,4-c][1,3,2]dioxaphosphole monohydrate}, [Et(3)NH(2',3'-cGMP)].H(2)O or C(6)H(16)N(+).C(10)H(11)N(5)O(7)P(-).H(2)O, (II), reveal different nucleobase orientations, viz. anti in (I) and syn in (II). These are stabilized by different inter- and intramolecular hydrogen bonds. The structures also exhibit different ribose ring puckering [(4)E in (I) and (3)T(2) in (II)] and slightly different 1,3,2-dioxaphospholane ring conformations, viz. envelope in (I) and puckered in (II). Infinite ribbons of 2',3'-cAMP(-) and helical chains of 2',3'-cGMP(-) ions, both formed by O-H...O, N-H...X and C-H...X (X = O or N) hydrogen-bond contacts, characterize (I) and (II), respectively.

Cyclic AMP↗
PubMed2006

Two polymorphic forms of N-(4-chlorophenyl)-5-[(4-chlorophenyl)aminomethyl]-6-methyl-2-phenylpyrimidin-4-amine.

Two polymorphic forms of the title compound, C24H20Cl2N4, were obtained and characterized using X-ray crystal structure analysis. Colourless crystals of polymorph (Ia) were obtained from the oily mother residue. Recrystallization of polymorph (Ia) from an acetone-methanol mixture resulted in pale-yellow crystals of polymorph (Ib). The major feature distinguishing the two polymorphic forms is their interaction modes, and hence their packing arrangements. In the crystal structure of polymorph (Ia), there are N-H...N hydrogen bonds and also aromatic pi-pi stacking interactions between molecules. The molecules of polymorph (Ib) are linked by N-H...Cl hydrogen bonds only.

Chlorobenzenes↗
PubMed2006

Comparison of the methyl ester of L-tyrosine hydrochloride and its methanol monosolvate.

Solvent-free (2S)-methyl 2-ammonio-3-(4-hydroxyphenyl)propionate chloride, C10H14NO3+.Cl-, (I), and its methanol solvate, C10H14NO3+.Cl-.CH3OH, (II), are obtained from different solvents: crystallization from ethanol or propan-2-ol gives the same solvent-free crystals of (I) in both cases, while crystals of (II) were obtained by crystallization from methanol. The structure of (I) is characterized by the presence of two-dimensional layers linked together by N-H...Cl and O-H...Cl hydrogen bonds and also by C-H...O contacts. Incorporation of the methanol solvent molecule in (II) introduces additional O-H...O hydrogen bonds linking the two-dimensional layers, resulting in the formation of a three-dimensional network.

Crystallography, X-Ray↗
PubMed2006

Structure of dihydroxyacetone phosphate dimethyl acetal, a stable dihydroxyacetone phosphate precursor, in the crystalline state.

Crystal and molecular structures of four different salts of a dihydroxyacetone phosphate (DHAP) precursor, its dimethyl acetal [2,2-dimethoxy-1,3-propanediol phosphate, C(5)H(13)O(7)P, (MeO)(2)DHAP]: (cha)(2)[(MeO)(2)DHAP].H(2)O (6a), (cha)[(MeO)(2)DHAP] (6b), Na(2)[(MeO)(2)DHAP].5.75H(2)O (6c) and K(2)[(MeO)(2)DHAP].H(2)O (6d), along with the cyclohexylammonium (cha) salt of its phenyl ester (cha)[(MeO)(2)DHAP(Ph)] (6e) are described. In the (MeO)(2)DHAP mono- and dianions, slightly different orientation of the phosphate group in relation to the acetal carbon atom is observed, with a delicate tendency of phosphate group to be located antiperiplanar in the monoanions and anticlinal in the dianions. The 2,2-dimethoxy-1,3-propandiol moiety, (MeO)(2)DHA, seems to be very rigid and its conformation is independent of phosphorylation, the ionization state of the inserted phosphate group and its additional substitution. The overall structures of the cyclohexylammonium (6a,b) and potassium salts (6d) have a double-layered architecture, while the sodium cation network in 6c forms the system of channels, which are filled up with the [(MeO)(2)DHAP](2-) ions. The different architectures of 6c and 6d crystals result from the different ways in which the relevant dianions coordinate to sodium and potassium ions and affect also the hydrogen bonding system observed in 6c and 6d crystals.

Acetals↗
PubMed2005

X-ray structure of the dipotassium salt of D-mannose 1-phosphate 3.25 hydrate.

The first crystal structure of mannose 1-phosphate is described. The dipotassium hydrate salt crystallizes in the P2(1)2(1)2 space group. There are two independent dianions (I and II) in the asymmetric unit, which are alpha anomers adopting the 4C(1) chair conformation. The main difference between the two mannose 1-phosphate dianions is the orientation of the phosphate group with relation to the pyranosyl ring. In I, one of the phosphate oxygen atoms is antiperiplanar positions with respect to carbon atom C-1, whereas the two others are situated synclinally. The corresponding orientations of the terminal phosphate oxygen atoms in II are synperiplanar and anticlinal. The potassium cations are six- and seven-coordinate, mainly with O atoms of hydroxyl groups and water molecules. There are potassium channels extending along the c-axis. In the packing arrangement, water molecules and mannose phosphate groups also define two different types of layers parallel to a-axis. Within water channels there are extensive hydrogen-bonding networks.

Carbohydrate Conformation↗
PubMed2005

Lanthanide complexes of chiral 3 + 3 macrocycles derived from (1R,2R)-1,2-diaminocyclohexane and 2,6-diformyl-4-methylphenol.

The enantiopure amine macrocycle H(3)L, as well as the parent macrocyclic Schiff base H(3)L1, the 3 + 3 condensation product of (1R,2R)-1,2-diaminocyclohexane and 2,6-diformyl-4-methylphenol, are able to form mononuclear complexes with lanthanide(III) ions. The lanthanide(III) complexes of H(3)L have been studied in solution using NMR spectroscopy and electrospray mass spectrometry. The NMR spectra indicate the presence of complexes of low C(1) and C(2) symmetry. The (1)H and (13)C NMR signals of the Lu(III) complex obtained from H(3)L have been assigned on the basis of COSY, TOCSY, NOESY, ROESY and HMQC spectra. The NMR data reveal unsymmetrical binding of lanthanide(III) ion and the presence of a dynamic process corresponding to rotation of Lu(III) within the macrocycle. The [Ln(H(4)L)(NO(3))(2)](NO(3))(2)(Ln = Sm(III), Eu(III), Dy(III), Yb(III) and Lu(III)) complexes of the cationic ligand H(4)L(+) have been isolated in pure form. The X-ray analysis of the [Eu(H(4)L)(NO(3))(2)](NO(3))(2) complex confirms the coordination mode of the macrocycle determined on the basis of NMR results. In this complex the europium(III) ion is bound to three phenolate oxygen atoms and two amine nitrogen atoms of the monoprotonated macrocycle H(4)L(+), as well as to two axial bidendate nitrate anions. In the presence of a base, mononuclear La(III), Ce(III) and Pr(III) complexes of the deprotonated form of the ligand L(3-) can be obtained. When 2 equivalents of Pr(III) are used in this synthesis Na(3)[Pr(2)L(NO(3))(2)(OH)(2)](2)NO(3).5H(2)O is obtained. The NMR, ES MS and an X-ray crystal model of this complex show coordination of two Pr(III) ions by the macrocycle L. The X-ray crystal structure of the free macrocycle H(3)L1 has also been determined. In contrast to macrocyclic amine H(3)L, the Schiff base H(3)L1 adopts a cone-type conformation resembling calixarenes.

Cations↗
PubMed2005

New 2+2, 3+3 and 4+4 macrocycles derived from 1,2-diaminocyclohexane and 2,6-diformylpyridine.

Two new Schiff base macrocycles - a 4+4 condensation product and a meso-type 2+2 condensation product - were obtained in a reaction of trans-1,2-diaminocyclohexane and 2,6-diformylpyridine. Reduction of these compounds led to the corresponding 4+4 and 2+2 macrocyclic amines. The macrocycles were characterised by NMR spectroscopy and electrospray mass spectrometry. The symmetry and stereochemistry of these macrocycles, as well as of new 3+3 and 4+4 diastereomers identified in solution, has been established. X-Ray structures of the 2+2 and 4+4 Schiff base macrocycles confirm the configurations determined on the basis of spectroscopic investigations. The crystal structures reveal that the centres of the square-shaped 4+4 macrocycles form channels as a result of columnar stacking.

Crystallography, X-Ray↗
PubMed2005

1H NMR investigation of high-spin and low-spin iron(III) meso-ethynylporphyrins.

The 1H NMR spectra of iron(III) 5-ethynyl-10,15,20-tri(p-tolyl)porphyrin [(ETrTP)Fe(III)X(n)], iron(III) 5-(phenylethynyl)-10,15,20-tri(p-tolyl)porphyrin [(PETrTP)Fe(III)X(n)], iron(III) 5-(phenylbutadiynyl)-10,15,20-tri(p-tolyl)porphyrin [(PBTrTP)Fe(III)X(n)], iron(III) 5,10,15,20-tetra(phenylethynyl)porphyrin [(TPEP)Fe(III)X(n)], iron(III) 1,4-bis-[10,15,20-tri(p-tolyl)porphyrin-5-yl]-1,3-butadiyne {[(TrTP)Fe(III)X(n)]2 B}, and 5,10,15-triphenylporphyrin [(TrPP)Fe(III)X(n)] have been studied to elucidate the impact of meso-ethynyl substitution on the electronic structure and spin density distribution of high-spin (X = Cl-, n = 1) and low-spin (X = CN-, n = 2) derivatives. The meso substituents, i.e., ethynyl, phenylethynyl, and phenylbutadiynyl, provided insight into the efficiency of spin density delocalization along structural elements that are typically applied to transmit electronic effects along multipart polyporphyrinic systems. The positive spin density localized at the meso-carbon of high-spin iron(III) ethynylporphyrins is effectively delocalized along the ethyne or butadiyne fragment as illustrated by the comparison of isotropic shifts of C(meso)-H and -CC-H determined for (TrPP)Fe(III)Cl (-82.6 ppm, 293 K) and (ETrTP)Fe(III)Cl (-49.5 ppm, 298 K). The replacement of the ethynyl hydrogen by phenyl or phenylethynyl provided evidence for the pi spin density distribution around the introduced phenyl ring. An analysis of the isotropic shifts for the low-spin bis-cyanide iron(III) porphyrins series reveals the analogous mechanism of spin density transfer. Treatment of high-spin [(TrTP)Fe(III)Cl]2 B with a base resulted in formation of the cyclic [(TrTP)Fe(III)OFe(III)(TrTP)B]2 complex linked by two mu-oxo bridges. (TPEP)H2 has been characterized by X-ray crystallography as a porphyrin dication where two molecules of trifluoroacetic acid associate with two coordinated trifluoroacetate anions. The X-ray structure of bis-tetrahydrofuran 1,4-bis[10,15,20-tri(p-tolyl)porphyrinatozinc(II)-5-yl]-1,3-butadiyne complex {[(TrTP)Zn(II)(THF)]2 B} reveals two parallel, non-coplanar [(TrTP)Zn(THF)] subunits linked by the linear butadiyne moiety.

Journal Article↗
PubMed2005

N-[tert-Butoxycarbonylglycyl-(Z)-alpha,beta-dehydrophenylalanylglycyl-(E)-alpha,beta-dehydrophenylalanylphenylalanyl]-4-nitroaniline ethanol solvate.

The alpha,beta-dehydrophenylalanine residues influence the conformation of the title pentapeptide Boc0-Gly1-Delta(Z)Phe2-Gly3-Delta(E)Phe4-L-Phe5-p-NA ethanol solvate, C42H43N7O9.C2H5OH. The first unsaturated phenylalanyl (Delta(Z)Phe2) and the third glycyl (Gly3) residues form a type I beta turn, while the second unsaturated phenylalanyl (Delta(E)Phe4) and the last phenylalanyl (L-Phe5) residues are part of a type II beta turn. All the amino acids in the peptide are linked trans to one another. The crystal structure is stabilized by intra- and intermolecular hydrogen bonds.

Aniline Compounds↗
PubMed2005

Solid-state molecular organization and solution behavior of methane-1,1-diphosphonic acid derivatives of heterocyclic amines: the role of the topochemical ring modification and the intramolecular hydrogen bonds in monosubstituted piperid-1-ylmethane-1,1-diphosphonic acids.

The crystal structures of 3-methylpiperid-1-ylmethane-1,1-diphosphonic (2), 4-methylpiperid-1-ylmethane-1,1-diphosphonic (3), 2-ethylpiperid-1-ylmethane-1,1-diphosphonic (4), and 2-methylpiperid-1-ylmethane-1,1-diphosphonic (5) acids have been determined and are discussed with respect to their molecular organization and crystal-packing preferences. The chair conformation, predominant also in solution, favors equatorial positioning of the bulky substituents of the heterocyclic N and C atoms. The molecular geometry also provides access to intramolecular hydrogen-bond formation between the axial protons located on the nitrogen atoms, as well as the carbon atoms closest to it, and phosphonic/phosphonate oxygen atoms. The molecules preferably arrange in monolayers, observed in all crystals with an exception of 3. The layers are held in place in the third direction through van der Waals interactions. The analysis of two-dimensional hydrogen-bonded networks is concentrated on revealing how the substituent's topology of the molecule affects the solid-state organization in well-defined structures and is aimed at unraveling the consequences and the possible conformational changes by stepwise network disruption upon crystal dissolution in water. The solution NMR studies are focused on revealing the role that the topochemistry of the substituent plays for the stereodynamics in 2-5. It is demonstrated that in contrast to piperid-1-ylmethane-1,1-diphosphonic acid (1), in which the ring inversion/rotation around the C-N bond concerted with the N-H...O hydrogen-bond breaking/formation process leads to a mixture of two interconverting conformers, the concerted N-H...O breaking/rotation/N-H...O formation process in 2 and 3 allows for a predominance of one conformer in solution. However, placement of a substituent at 2-position in the ring hampers the rotation around the C-N bond; this makes 4 and 5 significantly less flexible relative to compounds 1-3. In addition, both compounds 4 and 5 are proved to exist as a mixture of two conformers, the equilibrium of which in acidic solution is shifted towards the conformer found in solid state. In alkaline solutions of 4 and 5, the equilibrium is shifted towards the conformer that is forced by the flipping of the heterocyclic ring. These results correlate well with recently documented differences in the biological potency of this group of compounds.

Amines↗
PubMed2005

Cyclic water pentamers in triclinic crystals of brucinium L-glycerate.

Brucinium L-glycerate 4.75-hydrate, C23H27N2O4+.C3H5O4-.4.75H2O, was obtained by racemic resolution of DL-glyceric acid. This is the first report of triclinic crystals containing brucine. The water and L-glycerate anions form tapes built up of pentamers formed by water and carboxy O atoms, and this appears to be the reason for the low symmetry of the crystal.

Journal Article↗
PubMed2005

9-(2-Chloroethylamino)acridine monohydrate and its precursor 9-phenoxyacridine.

The title compounds, C15H13ClN2.H2O, (I), and C19H13NO, (II), form monoclinic crystals. Arranged in a 'head-to-tail' manner, the molecules of the amine form (I) lie along the b axis in layers that are linked by a network of hydrogen bonds involving the endocyclic N atom, the H atom at the exocyclic N atom and all the atoms of the solvent water molecule. Molecules of (II), with the phenoxy group nearly perpendicular to the acridine moiety, are arranged in pairs related by a center of symmetry and stabilized via two C-H...N contacts; the latter are linked via a network of further C-H...N contacts and non-specific dispersive interactions.

Journal Article↗
PubMed2004

Ethyltriphenylphosphonium perrhenate and (iodomethyl)triphenylphosphonium perrhenate.

Ethyltriphenylphosphonium perrhenate, (C(20)H(20)P)[ReO(4)], and (iodomethyl)triphenylphosphonium perrhenate, (C(19)H(17)IP)[ReO(4)], have been crystallized from 2-propanol. Both crystal structures consist of phosphonium cations and perrhenate anions. The cations show the typical propeller-like geometry. In both crystals, the positions of the nearly tetrahedral anions are stabilized by weak C-H...O hydrogen bonds, and for the latter compound, I...pi interactions also occur.

Journal Article↗