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1.
Elizabeth M. Kikolski Hugh W. Thompson Roger A. Lalancette 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(7):o394-o396
The asymmetric unit of the title compound, C24H36O4, contains three molecules, all differing in their side‐chain conformations and all linked by hydrogen bonding confined entirely within a three‐molecule block. One connection is of the acid‐to‐ketone type [O⋯O = 2.7055 (19) Å and O—H⋯O = 180°] and the other involves carboxyl pairing [O⋯O = 2.6485 (18) and 2.6598 (18) Å, and O—H⋯O = 168 and 174°]. Numerous intermolecular C—H⋯O close contacts connect neighbouring molecules. 相似文献
2.
Mark Davison Elizabeth M. Kikolski Roger A. Lalancette Hugh W. Thompson 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o449-o451
In the title compound, C10H16O3, the two molecules of the asymmetric unit form acid‐to‐ketone hydrogen‐bonded chains. The two species differ only very slightly and are related by a pseudo‐center, so that the apparent translational relationship among the units of the hydrogen‐bonded chain is actually a pseudo‐translation, with the molecules alternating in type. Two counterdirectional pairs of chains proceed through each cell [O⋯O = 2.743 (2) and 2.683 (2) Å, and O—H⋯O = 171 (3) and 157 (3)°]. Three intermolecular C—H⋯O close contacts were found, involving all three O atoms of one of the molecules. 相似文献
3.
Roger A. Lalancette Hugh W. Thompson 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(5):o274-o276
The title keto acid crystallizes as a solvate, C21H25FO4·C2H4O2, with two molecules each of steroid and acetic acid per asymmetric unit. The former are approximately parallel, with opposite end‐to‐end orientation, and form translational carboxyl‐to‐ketone hydrogen‐bonding catemers [O⋯O = 2.679 (6) and 2.650 (5) Å, and O—H⋯O = 165 and 162°] that involve the 3‐ketone group and follow the a axis. The acetic acid molecules are paired by hydrogen bonding, and neither they nor the F atom nor the 11‐ketone group play any overt role in the hydrogen‐bonding scheme of the steroid. Intermolecular C—H⋯O=C close contacts involving three different neighboring molecules exist to the 11‐ketone group, the steroidal carboxyl group and one of the acetic acid molecules. 相似文献
4.
Hugh W. Thompson Roger A. Lalancette 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(10):o580-o582
In the title compound, C15H24O3, derived from a naturally occurring sesquiterpenoid, the asymmetric unit consists of two molecules differing by 167.4 (8)° in the rotational conformation of the carboxyl group. Each molecule aggregates separately with its own type as carboxyl‐to‐ketone hydrogen‐bonding catemers [O⋯O = 2.715 (6) and 2.772 (6) Å, and O—H⋯O = 169 and 168°]. This generates two crystallographically independent single‐strand hydrogen‐bonding helices passing through the cell in the b direction, with opposite end‐to‐end orientations. One intermolecular C—H⋯O=C close contact exists for the carboxyl group of one of the molecules. The structure is isostructural with that of a closely related unsaturated keto acid reported previously. 相似文献
5.
Christopher Glidewell John N. Low Janet M. S. Skakle James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o15-o18
2‐Amino‐5‐nitrothiazole crystallizes from solution in ethanol as a monosolvate, C3H3N3O2S·C2H6O, in which the thiazole component has a strongly polarized molecular–electronic structure. The thiazole molecules are linked into centrosymmetric dimers by paired N—H⋯N hydrogen bonds [H⋯N = 2.09 Å, N⋯N = 2.960 (6) Å and N—H⋯N = 169°], and these dimers are linked by the ethanol molecules, via a two‐centred N—H⋯O hydrogen bond [H⋯O = 1.98 Å, N⋯O = 2.838 (5) Å and N—H⋯O = 164°] and a planar asymmetric three‐centred O—H⋯(O)2 hydrogen bond [H⋯O = 2.07 and 2.53 Å, O⋯O = 2.900 (5) and 3.188 (5) Å, O—H⋯O = 169 and 136°, and O⋯H⋯O = 55°], into sheets built from alternating (8) and (38) rings. These sheets are triply interwoven. 相似文献
6.
Hugh W. Thompson Marie L. Cot Roger A. Lalancette 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(10):o727-o729
The title compound, (1R)‐4,7,7‐trimethyl‐3‐oxobicyclo[2.2.1]heptane‐2‐endo‐acetic acid, C12H18O3, like its lower homolog, forms carboxyl‐to‐ketone hydrogen‐bonding catemers (Z′ = 2) [O⋯O = 2.729 (5) and 2.707 (5) Å, and O—H⋯O = 165 and 170°] with screw‐related components. The two molecules of the asymmetric unit differ slightly in conformation and produce two counter‐aligned hydrogen‐bonding chains, both aligned with the b axis. Close intermolecular C—H⋯O=C contacts exist for the ketone group of one molecule and for both the ketone and carboxyl functions in the other. 相似文献
7.
Christopher Glidewell John N. Low Janet M. S. Skakle James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o120-o124
Molecules of 2‐(2‐nitrophenylaminocarbonyl)benzoic acid, C14H10N2O5, are linked into centrosymmetric R(8) dimers by a single O—H⋯O hydrogen bond [H⋯O = 1.78 Å, O⋯O = 2.623 (2) Å and O—H⋯O = 178°] and these dimers are linked into sheets by a single aromatic π–π stacking interaction. The isomeric compound 2‐(4‐nitrophenylaminocarbonyl)benzoic acid crystallizes in two polymorphic forms. In the orthorhombic form (space group P212121 with Z′ = 1, crystallized from ethanol), the molecules are linked into sheets of R(22) rings by a combination of one N—H⋯O hydrogen bond [H⋯O = 1.96 Å, N⋯O = 2.833 (3) Å and N—H⋯O = 171°] and one O—H⋯O hydrogen bond [H⋯O = 1.78 Å, O⋯O = 2.614 (3) Å and O—H⋯O = 173°]. In the monoclinic form (space group P21/n with Z′ = 2, crystallized from acetone), the molecules are linked by a combination of two N—H⋯O hydrogen bonds [H⋯O = 2.09 and 2.16 Å, N⋯O = 2.873 (4) and 2.902 (3) Å, and N—H⋯O = 147 and 141°] and two O—H⋯O hydrogen bonds [H⋯O = 1.84 and 1.83 Å, O⋯O = 2.664 (3) and 2.666 (3) Å, and O—H⋯O = 166 and 174°] into sheets of some complexity. These sheets are linked into a three‐dimensional framework by a single C—H⋯O hydrogen bond [H⋯O = 2.45 Å, C⋯O = 3.355 (4) Å and C—H⋯O = 160°]. 相似文献
8.
Carlos E. M. Carvalho Solange M. S. V. Wardell James L. Wardell Janet M. S. Skakle John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o28-o32
Molecules of the title compounds N2‐(benzoyloxy)benzamidine, C14H12N2O2, (I), N2‐(2‐hydroxybenzoyloxy)benzamidine, C14H12N2O3, (II), and N2‐benzoyloxy‐2‐hydroxybenzamidine, C14H12N2O3, (III), all have extended chain conformations, with the aryl groups remote from one another. In (I), the molecules are linked into chains by a single N—H⋯N hydrogen bond [H⋯N = 2.15 Å, N⋯N = 3.029 (2) Å and N—H⋯N = 153°] and these chains are linked into sheets by means of aromatic π–π stacking interactions. There is one intramolecular O—H⋯O hydrogen bond in (II), and a combination of one three‐centre N—H⋯(N,O) hydrogen bond [H⋯N = 2.46 Å, H⋯O = 2.31 Å, N⋯N = 3.190 (2) Å, N⋯O = 3.146 (2) Å, N—H⋯N = 138° and N—H⋯O = 154°] and one two‐centre C—H⋯O hydrogen bond [H⋯O = 2.46 Å, C⋯O = 3.405 (2) Å and C—H⋯O = 173°] links the molecules into sheets. In (III), an intramolecular O—H⋯N hydrogen bond and two N—H⋯O hydrogen bonds [H⋯O = 2.26 and 2.10 Å, N⋯O = 2.975 (2) and 2.954 (2) Å, and N—H⋯O = 138 and 163°] link the molecules into sheets. 相似文献
9.
S. Thamotharan V. Parthasarathi Ranju Gupta D. P. Jindal Anthony Linden 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o405-o407
The asymmetric unit of the title compound, C25H30FN3O·0.5CH3OH, contains four symmetry‐independent steroid and two methanol molecules. The conformations of the independent steroid molecules are very similar. Intermolecular O—H⋯O hydrogen bonds create two independent chains, each of which links two of the independent steroid molecules plus one methanol molecule via a co‐operative O—H⋯O—H⋯O—H pattern. Intermolecular C—H⋯O and C—H⋯F interactions are also observed. 相似文献
10.
Hugh W. Thompson Roger A. Lalancette 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):o22-o23
The title keto acid, (+)‐23,24‐dinor‐3‐oxochol‐4‐en‐22‐oic acid, C22H32O3, forms carboxyl‐to‐ketone hydrogen‐bonding catemers [O?O = 2.699 (4) Å and O—H?O = 173°], linking molecules screw‐related in b. The four molecules in the cell form two parallel counter‐directional chains, screw‐related in a. Intermolecular C—H?O=C close contacts to different neighboring molecules were found for the ketone and the acid. 相似文献
11.
Carolina Gastone Jordi Puiggalí Merc Font‐Bardia Lourdes Urpí 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o498-o500
Crystals of the title compound, C8H14ClNO3, belong to the space group Cc and are characterized by an asymmetric unit containing two molecules, both with a twisted conformation. The molecular packing is stabilized by N—H⋯O=C hydrogen bonds between the amide groups of molecules with the same conformation. In addition, hydrogen‐bonded cyclic carboxylic acid dimers are established between molecules with a different conformation. The ClCH2—CONH bond has a cis conformation in order to favour an intramolecular Cl⋯HN electrostatic interaction. Weak intra‐ and intermolecular CH2⋯O=C interactions are also present. 相似文献
12.
Bernard Marciniak 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):o252-o254
The asymmetric unit of the title compound, C10H8O2, contains two planar symmetry‐independent molecules linked by an O—H⋯O hydrogen bond. In the crystal structure, molecules are linked into infinite chains of rings, formed by a combination of O—H⋯O and C—H⋯O hydrogen bonds, and additionally reinforced by π–π stacking interactions. Adjacent chains are connected by weak C—H⋯π interactions. 相似文献
13.
G. Y. S. K. Swamy K. Ravikumar B. Sridhar I. Mahender K. V. N. S. Srinivas 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o495-o497
The title compound [systematic name: 5‐hydroxy‐2‐(3‐hydroxy‐4,5‐dimethoxyphenyl)‐3,6,7‐trimethoxy‐4H‐chromen‐4‐one], C20H20O9, was isolated from the seeds of Cleom viscosa Linn. Two independent molecules (A and B) are present in the asymmetric unit with almost similar conformations. The dihedral angles between the fused chromene ring system and the benzene ring bonded to it in molecules A and B are 4.2 (1) and 12.7 (1)°, respectively. The hydroxy O atoms are involved in intramolecular hydrogen bonding. The molecules are linked by C—H⋯O and O—H⋯O interactions into chains of edge‐fused R33(22) rings. Aromatic π–π and weak C—H⋯π(arene) interactions are also observed. 相似文献
14.
Gordana Pavlovi Lidija Barii Vladimir Rapi Veronika Kova
《Acta Crystallographica. Section C, Structural Chemistry》2003,59(2):m55-m57
Heteroannularly substituted ferrocene derivatives can act as model systems for various hydrogen‐bonded assemblies of biomolecules formed, for instance, by means of O—H⋯O and N—H⋯O hydrogen bonding. The crystal structure analysis of 1′‐(tert‐butoxycarbonylamino)ferrocene‐1‐carboxylic acid, [Fe(C10H14NO2)(C6H5O2)] or (C5H4COOH)Fe(C5H4NHCOOC(CH3)3, reveals two independent molecules within the asymmetric unit, and these are joined into discrete dimers by two types of intermolecular hydrogen bonds, viz. O—H⋯O and N—H⋯O. The –COOH and –NHCOOR groups are archetypes for dimer formation via two eight‐membered rings. The O—H⋯O hydrogen bonds [2.656 (3) and 2.663 (3) Å] form a cyclic carboxylic acid dimer motif. Another eight‐membered ring is formed by N—H⋯O hydrogen bonds [2.827 (3) and 2.854 (3) Å] between the N—H group and an O atom of another carbamoyl moiety. The dimers are assembled in a herring‐bone fashion in the bc plane. 相似文献
15.
Hamid Reza Nasiri M. Gregor Madej C. Roy D. Lancaster Harald Schwalbe Michael Bolte 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(12):o671-o673
The title compound, C14H12O4, forms crystals which appear monoclinic but are actually twinned triclinic. The asymmetric unit consists of two similar molecules, which differ only in the conformation of the 3‐oxobutyl side chain. The molecular conformation is characterized by an intramolecular O—H⋯O hydrogen bond between the hydroxy group and the adjacent carbonyl O atom. The crystal structure is stabilized by O—H⋯O hydrogen bonds connecting the molecules into zigzag chains running along the b axis. 相似文献
16.
Cem Cüneyt Ersanl idem Albayrak Mustafa Odabaolu Carsten Thne Ahmet Erdnmez 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o133-o135
The structure of the title compound, C18H20ClN3O5, displays the characteristic features of azobenzene derivatives. Intramolecular N—H⋯O, weak intramolecular C—H⋯O, and intermolecular O—H⋯O and C—H⋯O interactions influence the conformation of the molecules and the crystal packing. Intermolecular hydrogen bonds link the molecules into infinite chains, and the title compound adopts the keto–amine tautomeric form. The azobenzene moiety of the molecule has a trans configuration. The molecule is not planar, and the dihedral angle between the two phenyl rings is 35.6 (2)°. 相似文献
17.
Simon J. Garden Marilza B. Corrêa Angelo C. Pinto James L. Wardell John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):o234-o238
In ethyl N‐[2‐(hydroxyacetyl)phenyl]carbamate, C11H13NO4, all of the non‐H atoms lie on a mirror plane in the space group Pnma; the molecules are linked into simple chains by a single C—H⋯O hydrogen bond. The molecules of ethyl N‐[2‐(hydroxyacetyl)‐4‐iodophenyl]carbamate, C11H12INO4, are linked into sheets by a combination of O—H⋯I and C—H⋯O hydrogen bonds and a dipolar I⋯O contact. Ethyl N‐[2‐(hydroxyacetyl)‐4‐methylphenyl]carbamate, C12H15NO4, crystallizes with Z′ = 2 in the space group P; pairs of molecules are weakly linked by an O—H⋯O hydrogen bond and these aggregates are linked into chains by two independent aromatic π–π stacking interactions. 相似文献
18.
Abdurrahman engül Nevzat Karaday 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(8):o539-o541
The title compound, C27H27N5O3·H2O, is built up from pyrazolinone, phenyl and acetophenone oxime moieties. The 2‐phenyl substituent is nearly perpendicular to the pyrazolinone ring, with a dihedral angle of 87.66 (1)°. The acetophenone oxime moieties are twisted out of the pyrazolinone‐ring plane by 47.04 (1)°. The molecules in the crystal pack in an antiparallel fashion and are held together by hydrogen‐bonded water molecules and intermolecular O—H⋯O and O—H⋯N hydrogen bonds. 相似文献
19.
Mark Davison Hugh W. Thompson Roger A. Lalancette 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(4):o242-o244
The 68.5:31.5 mixture of diastereoisomers obtained in the synthesis of the title compound, C12H16O3, yielded sharply melting crystals containing the same ratio of epimers, in a disordered crystallographic arrangement. The disorder resides almost entirely in the carboxymethyl side chain, but places the two sets of carboxyl O atoms at nearly identical paired spatial positions. Neither component displays significant carboxyl disorder, and the molecules aggregate as hydrogen‐bonded carboxyl‐to‐ketone catemers [O⋯O = 2.673 (4) Å and O—H⋯O = 158°] having glide‐related components, with centrosymmetrically related pairs of chains following axes perpendicular to b. Close intermolecular C—H⋯O contacts exist for both the ketone and the carboxyl group. The energetics of the epimers and of their crystallization mode are discussed. 相似文献
20.
Muharrem Diner Namk
zdemir brahim Ylmaz Alaaddin ukuroval Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):o674-o676
In the title compound, C17H20N2O3, the cyclobutane ring is puckered, with a dihedral angle of 19.11 (15)°. The 1‐phenyl and 3‐[1‐hydroxyimino‐2‐(succinimido)ethyl] groups are in cis positions. The molecules are linked by O—H⋯O and C—H⋯π(benzene) interactions, forming a two‐dimensional network. 相似文献