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1.
Marius Bruvoll Selma Dizdarevic Nina Fimland Jasmina Hafizovic Carl Henrik Grbitz Helen Therese Kalfjs Kristian Vestli Alexander Krivokapic 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(1):o22-o25
The structures of the title dipeptides, C9H18N2O4·0.33H2O, C12H16N2O4 and C8H16N2O4S·0.34H2O, complete a series of investigations focused on l ‐Xaa‐l ‐serine peptides, where Xaa is a hydrophobic residue. All three structures are divided into hydrophilic and hydrophobic layers. The hydrophilic layers are thin for l ‐phenylalanyl‐l ‐serine, rendered possible by an unusual peptide conformation, and thick for l ‐isoleucyl‐l ‐serine and l ‐methionyl‐l ‐serine, which include cocrystallized water molecules on the twofold axes. 相似文献
2.
Carl Henrik Grbitz 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):575-576
A new type of molecular arrangement for dipeptides is observed in the crystal structure of l ‐phenylalanyl‐l ‐alanine dihydrate, C12H16N2O3·2H2O. Two l ‐Phe and two l ‐Ala side chains aggregate into large hydrophobic columns within a three‐dimensional hydrogen‐bond network. 相似文献
3.
Carl Henrik Grbitz 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o533-o536
The crystal structure of N‐(l ‐2‐aminobutyryl)‐l ‐alanine, C7H14N2O3, is closely related to the structure of l ‐alanyl‐l ‐alanine, both being tetragonal, while the retro‐analogue 2‐(l ‐alanylamino)‐l ‐butyric acid 0.33‐hydrate, C7H14N2O3·0.33H2O, forms a new type of molecular columnar structure with three peptide molecules in the asymmetric unit. 相似文献
4.
Alicja Janik Anna Chyra Katarzyna Stadnicka 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(10):o572-o575
The crystal structure of a protected l ‐tyrosine, namely N‐acetyl‐l ‐tyrosine methyl ester monohydrate, C12H15NO4·H2O, was determined at both 293 (2) and 123 (2) K. The structure exhibits a network of O—H...O and N—H...O hydrogen bonds, in which the water molecule plays a crucial role as an acceptor of one and a donor of two hydrogen bonds. Molecules of water and of the protected l ‐tyrosine form hydrogen‐bonded layers perpendicular to [001]. C—H...π interactions are observed in the hydrophobic regions of the structure. The structure is similar to that of N‐acetyl‐l ‐tyrosine ethyl ester monohydrate [Soriano‐García (1993). Acta Cryst. C 49 , 96–97]. 相似文献
5.
Carl Henrik Grbitz 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):o730-o732
The side chains of l ‐alanyl‐l ‐methionine hemihydrate, C8H16N2O3S·0.5H2O, form hydrophobic columns within a three‐dimensional hydrogen‐bond network that includes extended polymers of cocrystallized water molecules and Cα—H⋯S interactions. 相似文献
6.
Carl Henrik Grbitz 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(11):o531-o534
Dipeptides may form nanotubular structures with pore diameters in the range 3.2–10 Å. These compounds normally contain at least one and usually two hydrophobic residues, but l ‐His‐l ‐Ser hydrate, C9H14N4O4·3.7H2O, with two hydrophilic residues, forms large polar channels filled with ordered as well as disordered water molecules. 相似文献
7.
Lilianna Chciska Diana Frster Wolfgang Morgenroth Peter Luger 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o454-o457
The low‐temperature crystal and molecular structure analyses of two modifications of l ‐alanyl‐l ‐tyrosyl‐l ‐alanine with water, C15H21N3O5·2.63H2O [(I), at 9 K], and ethanol, C15H21N3O5·C2H5O [(II), at 20 K], solvent molecules in the crystal lattice show that the overall conformations of both modifications of the title tripeptide are practically the same. Moreover, despite the presence of different solvent molecules in the crystal lattice, the specific intermolecular interactions characteristic for individual tripeptide molecules of (I) and (II) are conserved. The crystal packing of the two modifications of Ala‐Tyr‐Ala differ from each other only in the solvent region. The tight arrangements of tripeptide molecules seem to be responsible for similar displacement parameters for all non‐H atoms, despite the different distances from the molecular centre of mass. Comparison of the displacement parameters between the room‐ and low‐temperature structures shows that an average Ueq value decrease of about 80% takes place at 9 K [for (I)] and 20 K [for (II)] with respect to room temperature. 相似文献
8.
Christian B. Hübschle Birger Dittrich Peter Luger 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o540-o542
In the title compound, C11H12N2O2·CH2O2, at 183 K. l ‐tryptophan appears in the zwitterionic form, while the formic acid molecule is neutral. The formic acid molecule is the donor in a strong O—H?O hydrogen bond to the carboxylate group of the tryptophan molecule, with a short O?O contact of 2.487 (2) Å. 相似文献
9.
Tadeusz Lis Agata Biaoska Zbigniew Ciunik Tomasz Popek 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):o88-o91
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. 相似文献
10.
Ina Hydal Helle Camilla Victoria Lkken Carl Henrik Grbitz Bjrn Dalhus 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(10):o771-o772
The peptide bond in the crystal structure of the title compound, C8H16N2O4, deviates substantially from planarity in the same manner as in other l ‐Ser‐l ‐Xaa dipeptides, where Xaa is a hydrophobic residue. 相似文献
11.
J. Wilson Quail Nargis Ismail M. Soledade C. Pedras Susan M. Boyetchko 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(5):o268-o271
The crystal structures of pseudophomins A and B, with primary structures β‐hydroxydecanoyl–l ‐Leu–d ‐Glu–d ‐allo‐Thr–d ‐Ile–d ‐Leu–d ‐Ser–l ‐Leu–d ‐Ser–l ‐Ile monohydrate, C55H97N9O16·H2O, and β‐hydroxydodecanoyl–l ‐Leu–d ‐Glu–d ‐allo‐Thr–d ‐Ile–d ‐Leu–d ‐Ser–l ‐Leu–d ‐Ser–l ‐Ile monohydrate, C57H101N9O16·H2O, new cyclic lipodepsipeptides isolated from Pseudomonas fluorescens strain BRG100, have been solved. The absolute configuration of pseudophomin A has been determined from anomalous dispersion and the stereochemistry of the β‐hydroxy acid group is R. 相似文献
12.
Graham Smith Urs D. Wermuth Jonathan M. White 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(12):o694-o698
The structures of two compounds of l ‐tartaric acid with quinoline, viz. the proton‐transfer compound quinolinium hydrogen (2R,3R)‐tartrate monohydrate, C9H8N+·C4H5O6−·H2O, (I), and the anhydrous non‐proton‐transfer adduct with quinaldic acid, bis(quinolinium‐2‐carboxylate) (2R,3R)‐tartaric acid, 2C10H7NO2·C4H6O6, (II), have been determined at 130 K. Compound (I) has a three‐dimensional honeycomb substructure formed from head‐to‐tail hydrogen‐bonded hydrogen tartrate anions and water molecules. The stacks of π‐bonded quinolinium cations are accommodated within the channels and are hydrogen bonded to it peripherally. Compound (II) has a two‐dimensional network structure based on pseudo‐centrosymmetric head‐to‐tail hydrogen‐bonded cyclic dimers comprising zwitterionic quinaldic acid species which are interlinked by tartaric acid molecules. 相似文献
13.
K. Anitha S. Athimoolam S. Natarajan 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):o567-o570
In the structure of l ‐prolinium picrate, C5H10NO2+·C6H2N3O7−, the Cγ atom of the pyrrolidine ring has conformational disorder. Both the major and minor conformers of the pyrrolidine ring adopt conformations intermediate between a half‐chair and an envelope. Both the cation and anion are packed through chelated three‐centred N—H⋯O hydrogen bonds. The prolinium cation connects two different picrate anions, leading to an infinite chain running along the b axis. In 2‐methylpyridinium picrate, C6H8N+·C6H2N3O7−, the cations and anions are packed separately along the a axis and are interconnected by N—H⋯O hydrogen bonds. Intramolecular contacts between phenolate O atoms and adjacent nitro groups are identified in both structures. A graph‐set motif of R12(6) is observed in both structures. 相似文献
14.
Katarzyna
lepokura Rafa Petrus 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(6):o265-o269
In the crystal structure of the methanol‐solvated monohydrated complex of l ‐histidine (His) with inosine 5′‐monophosphate (IMP), namely l ‐histidinium inosine‐5′‐phosphate methanol solvate monohydrate, C6H10N3O2+·C10H12N4O8P−·CH3OH·H2O, most of the interactions between IMP anions (anti/C3′‐endo/gauche–gauche conformers) are realized between the riboses and hypoxanthine bases in a trans sugar‐edge/sugar‐edge geometry, and between the phosphate groups. The base Watson–Crick edge is involved in additional methanol‐mediated IMP...MeOH...IMP contacts. Specific and nonspecific nucleotide–amino acid (IMP...His) interactions engage the Hoogsteen edges of the base and phosphate group, respectively. Additional stabilization of His...IMP contacts is provided by π–π stacking between the imidazolium ring of His and the hypoxanthine base of IMP. The results may indicate the possible recognition mechanism between His and IMP. 相似文献
15.
T. J. Emge A. Agrawal J. P. Dalessio G. Dukovic J. A. Inghrim K. Janjua M. Macaluso L. L. Robertson T. J. Stiglic Y. Volovik M. M. Georgiadis 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):e469-e471
The crystal structures of the title tryptophan‐containing dipeptides, C14H17N3O3·H2O, (I), C13H15N3O3·2H2O, (II), and C13H15N3O3·H2O, (III), respectively, contain at least one water molecule of solvation. As a result, the crystal packing of these compounds is composed of regions of water‐mediated hydrogen bonding and tryptophan ring‐to‐ring stacking separated by the length of the molecule. The tryptophan rings stack in a continuous layer that, when viewed edge‐on from the outermost part of the tryptophan ring, exhibits a herring‐bone motif. However, owing to the lack of direct overlap of adjacent rings, no degree of π contact or long‐range delocalization of ring systems is possible here. The overall molecular conformations of (I) and (III) contain a folding of one peptide over the other, such that a minimum in molecular volume occurs without any intramolecular hydrogen bonding. In these two dipeptides, extensive hydrogen bonding is observed to and from the single water molecule of solvation. In the crystal structure of (II), however, an extended molecule conformation complements a more extensive hydrogen‐bonding scheme involving two water molecules of solvation per dipeptide. 相似文献
16.
Carl Henrik Grbitz 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):500-502
A new `rule' for the association of hydrogen‐bond donors and acceptors in crystal structures is presented. It implies that ranks are assigned to each donor and each acceptor (1 is best, 2 is next best etc.), and that hydrogen bonds should be formed between donors and acceptors in rank order. l ‐Ser‐l ‐Ala, C6H12N2O4, is used together with its retroanalogue, l ‐Ala‐l ‐Ser, and three other pairs of dipeptide retroanalogues to illustrate this rule and the reasons why it may not always be followed. 相似文献
17.
Urs D. Wermuth Graham Smith Jonathan M. White 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):o353-o357
The structures of two brucinium (2,3‐dimethoxy‐10‐oxostrychnidinium) salts of the α‐hydroxy acids l ‐malic acid and l ‐tartaric acid, namely brucinium hydrogen (S)‐malate pentahydrate, C23H27N2O4+·C4H5O5−·5H2O, (I), and anhydrous brucinium hydrogen (2R,3R)‐tartrate, C23H27N2O4+·C4H5O6−,(II), have been determined at 130 K. Compound (I) has two brucinium cations, two hydrogen malate anions and ten water molecules of solvation in the asymmetric unit, and forms an extensively hydrogen‐bonded three‐dimensional framework structure. In compound (II), the brucinium cations form the common undulating brucine sheet substructures, which accommodate parallel chains of head‐to‐tail hydrogen‐bonded tartrate anion species in the interstitial cavities. 相似文献
18.
Carl Henrik Grbitz 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):o328-o330
The title compound, C20H21N3O3·0.75H2O, crystallizes as exceedingly thin fibers. The crystal packing arrangement is related to those of other hydrophobic dipeptides with phenylalanine residues, but the structure has pseudo‐tetragonal symmetry in an orthorhombic space group with four peptide molecules and three water molecules in the asymmetric unit. 相似文献
19.
Alok Sharma S. Thamotharan Siddhartha Roy M. Vijayan 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(3):o148-o152
The asymmetric unit of the dl ‐lysine complex of adipic acid [bis(dl ‐lysinium) adipate], 2C6H15N2O2+·C6H8O42−, contains a zwitterionic singly charged lysinium cation and half a doubly charged adipate anion (the complete anion has inversion symmetry). That of the l ‐lysine complex (lysinium hydrogen adipate), C6H15N2O2+·C6H9O4−, consists of a lysinium cation and a singly charged hydrogen adipate anion. In both structures, the lysinium cations organize into layers interconnected by adipate or hydrogen adipate anions. However, the arrangement of the molecular ions in the layer is profoundly different in the dl ‐ and l ‐lysine complexes. The hydrogen adipate anions in the l ‐lysine complex form linear arrays in which adjacent ions are interconnected by a symmetric O⋯H⋯O hydrogen bond. 相似文献
20.
Carl Henrik Grbitz 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(10):o589-o592
The crystal structure of l ‐methionyl‐l ‐alanine, C8H16N2O3S, is very similar to that of l ‐valyl‐l ‐alanine [Görbitz & Gundersen (1996). Acta Cryst. C 52 , 1764–1767] and other related dipeptides in space group P61, but there are seven molecules in the asymmetric unit. The Z value of 42 is the highest ever observed for a chiral molecule. 相似文献