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1.
Katarzyna
lepokura Tadeusz Lis 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(3):m76-m78
In the crystal structure of the title compond, alternatively called poly[calcium(II)‐di‐μ‐carboxymethylphosphonato], [Ca(C2H4O5P)2]n or [Ca(H2AP)2]n, one of the phosphonate O atoms of the phosphonocarboxylate monoanion lies nearly antiperiplanar (ap) to the carboxylic acid C atom. The phosphonate P atom is located −sc and +ac relative to the carboxylic acid O atoms. The overall structure has a layered architecture. The Ca2+ cations lie on a twofold axis and are bridged by the phosphonate O atoms to form chains along the c axis, giving layers parallel to (100). There are medium‐strength O—H⃛O and C—H⃛O hydrogen‐bonding interactions stabilizing the layers, and O—H⃛O hydrogen bonds connect adjacent layers. 相似文献
2.
Katarzyna
lepokura Tadeusz Lis 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(5):o315-o317
In the title compound, C11H15O6P, the six‐membered dioxaphosphorinane ring of the cyclic phosphate triester exists in a distorted chair conformation, with the phenoxy group in an axial position. The phenyl ring and both methoxy groups are in a trans–gauche orientation with respect to the 1,3,2‐dioxaphosphorinane ring. In the phosphate group, a significant deformation from the ideal tetrahedral shape is observed. The crystal structure is stabilized by a three‐dimensional network of C—H⋯O interactions. 相似文献
3.
Purine 3′:5′‐cyclic nucleotides are very well known for their role as the secondary messengers in hormone action and cellular signal transduction. Nonetheless, their solid‐state conformational details still require investigation. Five crystals containing purine 3′:5′‐cyclic nucleotides have been obtained and structurally characterized, namely adenosine 3′:5′‐cyclic phosphate dihydrate, C10H12N5O6P·2H2O or cAMP·2H2O, (I), adenosine 3′:5′‐cyclic phosphate 0.3‐hydrate, C10H12N5O6P·0.3H2O or cAMP·0.3H2O, (II), guanosine 3′:5′‐cyclic phosphate pentahydrate, C10H12N5O7P·5H2O or cGMP·5H2O, (III), sodium guanosine 3′:5′‐cyclic phosphate tetrahydrate, Na+·C10H11N5O7P−·4H2O or Na(cGMP)·4H2O, (IV), and sodium inosine 3′:5′‐cyclic phosphate tetrahydrate, Na+·C10H10N4O7P−·4H2O or Na(cIMP)·4H2O, (V). Most of the cyclic nucleotide zwitterions/anions [two from four cAMP present in total in (I) and (II), cGMP in (III), cGMP− in (IV) and cIMP− in (V)] are syn conformers about the N‐glycosidic bond, and this nucleobase arrangement is accompanied by Crib—H…Npur hydrogen bonds (rib = ribose and pur = purine). The base orientation is tuned by the ribose pucker. An analysis of data obtained from the Cambridge Structural Database made in the context of syn–anti conformational preferences has revealed that among the syn conformers of various purine nucleotides, cyclic nucleotides and dinucleotides predominate significantly. The interactions stabilizing the syn conformation have been indicated. The inter‐nucleotide contacts in (I)–(V) have been systematized in terms of the chemical groups involved. All five structures display three‐dimensional hydrogen‐bonded networks. 相似文献
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5.
Micha Sowa Katarzyna
lepokura Ewa Matczak‐Jon 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(7):o262-o265
Cocrystallization of baicalein with nicotinamide yields a 1:1 cocrystal [systematic name: pyridine‐3‐carboxamide–5,6,7‐trihydroxy‐2‐phenyl‐4H‐chromen‐4‐one (1/1)], C6H6N2O·C15H10O5. The asymmetric unit contains one baicalein and one nicotinamide molecule, both in neutral forms. Molecules in the cocrystal form column motifs stabilized by an array of intermolecular hydrogen bonds. 相似文献
6.
Barbara Szafranowska Katarzyna
lepokura Tadeusz Lis 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(12):i71-i82
The synthesis and crystal structures of a series of six crystalline potassium salts of hypodiphosphoric acid, H4P2O6, are reported, namely potassium hydrogen phosphonophosphonate, K+·H3P2O6−, (I), dipotassium dihydrogen hypodiphosphate monohydrate, 2K+·H2P2O62−·H2O, (II), dipotassium dihydrogen hypodiphosphate dihydrate, 2K+·H2P2O62−·2H2O, (III), pentapotassium hydrogen hypodiphosphate dihydrogen hypodiphosphate dihydrate, 5K+·HP2O63−·H2P2O62−·2H2O, (IV), tripotassium hydrogen hypodiphosphate tetrahydrate, 3K+·HP2O63−·4H2O, (V), and tetrapotassium hypodiphosphate tetrahydrate, 4K+·P2O64−·4H2O, (VI). All the hypodiphosphate anions, viz. H3P2O6−, H2P2O62−, HP2O63− and P2O64−, adopt a staggered conformation. The P—P bond lengths [2.1722 (7)–2.1892 (10) Å] do not depend on the basicity of the anion. The compounds are organized into different types of one‐, two‐ or three‐dimensional polymeric hydrogen‐bonded networks, or simply exist in the form of isolated or dimeric units. The coordination numbers of the K+ cations range from 6 to 9, and the cationic sublattices are polymeric one‐, two‐ or three‐dimensional networks, or isolated [KO6] or dimeric [K2O12] polyhedra. 相似文献
7.
Efficient Solvent‐Free Synthesis of Benzothiazine‐Fused Pyrrolo[3,4‐c]coumarins: Cycloaddition Reactions between Coumarin‐Based Dihydrobenzothiazoles and Isocyanides 下载免费PDF全文
Mehdi Khoobi Ali Ramazani Mohammad Mahdavi Alireza Foroumadi Saeed Emami Sang Woo Joo Katarzyna Ślepokura Tadeusz Lis Abbas Shafiee 《Helvetica chimica acta》2014,97(6):847-853
A new and unusual synthesis of benzothiazine‐fused pyrrolo[3,4‐c]coumarins, involving the ring‐opening of coumarin‐based dihydrobenzothiazoles and subsequent [4+1] cycloaddition reaction with isocyanides, was described. Thus, simple heating of various 3‐(2,3‐dihydro‐2‐methylbenzo[d]thiazol‐2‐yl)coumarins with isocyanides produced the title compounds in good yields under solvent‐free conditions. 相似文献
8.
Synthesis of Novel α‐(Acyloxy)‐α‐(quinolin‐4‐yl)acetamides by a Three‐Component Reaction between an Isocyanide,Quinoline‐4‐carbaldehyde,and Arenecarboxylic Acids 下载免费PDF全文
Jafar Taran Ali Ramazani Sang Woo Joo Katarzyna Ślepokura Tadeusz Lis 《Helvetica chimica acta》2014,97(8):1088-1096
Novel α‐(acyloxy)‐α‐(quinolin‐4‐yl)acetamides were synthesized by the Passerini three‐component reaction between an isocyanide, quinoline‐4‐carbaldehyde, and arenecarboxylic acids in H2O. The reactions were carried out in one pot at room temperature with quantitative yields. 相似文献
9.
Ewa Matczak‐Jon Katarzyna
lepokura Pawe Kafarski Izabela Skrzyska Marek Jon 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(6):o261-o266
The crystal structures of two salts, products of the reactions between [(5‐methyl‐2‐pyridyl)aminomethylene]bis(phosphonic acid) and 4‐aminopyridine or ammonia, namely bis(4‐aminopyridinium) hydrogen [(5‐methyl‐2‐pyridinio)aminomethylene]diphosphonate 2.4‐hydrate, 2C5H7N2+·C7H10N2O6P22−·2.4H2O, (I), and triammonium hydrogen [(5‐methyl‐2‐pyridyl)aminomethylene]diphosphonate monohydrate, 3NH4+·C7H9N2O6P23−·H2O, (II), have been determined. In (I), the Z configuration of the ring N—C and amino N—H bonds of the bisphosphonate dianion with respect to the Cring—Namino bond is consistent with that of the parent zwitterion. Removing the H atom from the pyridyl N atom results in the opposite E configuration of the bisphosphonate trianion in (II). Compound (I) exhibits a three‐dimensional hydrogen‐bonded network, in which 4‐aminopyridinium cations and water molecules are joined to ribbons composed of anionic dimers linked by O—H...O and N—H...O hydrogen bonds. The supramolecular motif resulting from a combination of these three interactions is a common phenomenon in crystals of all of the Z‐isomeric zwitterions of 4‐ and 5‐substituted (2‐pyridylaminomethylene)bis(phosphonic acid)s studied to date. In (II), ammonium cations and water molecules are linked to chains of trianions, resulting in the formation of double layers. 相似文献
10.
Ewa Matczak‐Jon Katarzyna
lepokura 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(11):o450-o456
In the crystal structures of the conformational isomers hydrogen {phosphono[(pyridin‐1‐ium‐3‐yl)amino]methyl}phosphonate monohydrate (pro‐E), C6H10N2O6P2·H2O, (Ia), and hydrogen {phosphono[(pyridin‐1‐ium‐3‐yl)amino]methyl}phosphonate (pro‐Z), C6H10N2O6P2, (Ib), the related hydrogen {[(2‐chloropyridin‐1‐ium‐3‐yl)amino](phosphono)methyl}phosphonate (pro‐E), C6H9ClN2O6P2, (II), and the salt bis(6‐chloropyridin‐3‐aminium) [hydrogen bis({[2‐chloropyridin‐1‐ium‐3‐yl(0.5+)]amino}methylenediphosphonate)] (pro‐Z), 2C5H6ClN2+·C12H16Cl2N4O12P42−, (III), chain–chain interactions involving phosphono (–PO3H2) and phosphonate (–PO3H−) groups are dominant in determining the crystal packing. The crystals of (Ia) and (III) comprise similar ribbons, which are held together by N—H...O interactions, by water‐ or cation‐mediated contacts, and by π–π interactions between the aromatic rings of adjacent zwitterions in (Ia), and those of the cations and anions in (III). The crystals of (Ib) and (II) have a layered architecture: the former exhibits highly corrugated monolayers perpendicular to the [100] direction, while in the latter, flat bilayers parallel to the (001) plane are formed. In both (Ib) and (II), the interlayer contacts are realised through N—H...O hydrogen bonds and weak C—H...O interactions involving aromatic C atoms. 相似文献