共查询到20条相似文献,搜索用时 31 毫秒
1.
Xiaohua Peng Frank Seela Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(2):o96-o98
In the title compound [systematic name: 7‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐2‐fluoro‐7H‐pyrrolo[2,3‐d]pyrimidin‐2‐amine], C11H13FN4O3, the conformation of the N‐glycosylic bond is between anti and high‐anti [χ = −110.2 (3)°]. The 2′‐deoxyribofuranosyl unit adopts the N‐type sugar pucker (4T3), with P = 40.3° and τm = 39.2°. The orientation of the exocyclic C4′—C5′ bond is −ap (trans), with a torsion angle γ = −168.39 (18)°. The nucleobases are arranged head‐to‐head. The crystal structure is stabilized by four intermolecular hydrogen bonds of types N—H⋯N, N—H⋯O and O—H⋯O. 相似文献
2.
Xiaohua Peng Hans Reuter Henning Eickmeier Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(10):o593-o595
In 4‐chloro‐7‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐7H‐pyrrolo[2,3‐d]pyrimidine‐2,4‐diamine, C11H14ClN5O3, the conformation of the N‐glycosylic bond is between anti and high‐anti [χ = −102.5 (6)°]. The 2′‐deoxyribofuranosyl unit adopts the C3′‐endo‐C4′‐exo (3T4) sugar pucker (N‐type) with P = 19.6° and τm = 32.9° [terminology: Saenger (1989). Landolt‐Börnstein New Series, Vol. 1, Nucleic Acids, Subvol. a, edited by O. Madelung, pp. 1–21. Berlin: Springer‐Verlag]. The orientation of the exocyclic C4′—C5′ bond is +ap (trans) with a torsion angle γ = 171.5 (4)°. The compound forms a three‐dimensional network that is stabilized by four intermolecular hydrogen bonds (N—H⋯O and O—H⋯N) and one intramolecular hydrogen bond (N—H⋯Cl). 相似文献
3.
Yang He Frank Seela Hans Reuter Eva‐Maria Heithoff 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):660-662
In the title compound, 4‐amino‐1‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐1H‐benzotriazole, C11H14N4O3, the conformation of the N‐glycosidic bond is in the high‐anti range [χ = ?77.1 (4)°] and the 2′‐deoxyribofuranose moiety adopts a 2′‐endo (2E) sugar puckering. The 5′‐hydroxyl group is disordered and has conformations ap with γ = 171.1 (3)° [occupation of 61.4 (3)%] and +sc with γ = 52.4 (6)° [occupation of 38.6 (3)%]. The nucleobases are stacked in the crystal state. 相似文献
4.
Frank Seela Yang He Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(4):o194-o196
In the title compound, 3‐amino‐2‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐6‐methyl‐1,2,4‐triazin‐5(2H)‐one, C9H14N4O4, the conformation of the N‐glycosidic bond is high‐anti and the 2‐deoxyribofuranosyl moiety adopts a North sugar pucker (2T3). The orientation of the exocyclic C—C bond between the –CH2OH group and the five‐membered ring is ap (gauche, trans). The crystal packing is such that the nucleobases lie parallel to the ac plane; the planes are connected via hydrogen bonds involving the five‐membered ring. 相似文献
5.
Frank Seela Kuiying Xu Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):o408-o410
In the title compound, 4‐amino‐7‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐5‐fluoro‐7H‐pyrrolo[2,3‐d]pyrimidine, C11H13FN4O3, the conformation of the glycosyl bond lies between anti and high anti [χ = −101.1 (3)°]. The furanose moiety adopts the S‐type sugar pucker (2T3), with P = 164.7 (3)° and τ = 40.1 (2)°. The extended structure is a three‐dimensional hydrogen‐bond network involving a C—H⋯F, two N—H⋯O and two O—H⋯O hydrogen bonds. 相似文献
6.
Frank Seela Khalil I. Shaikh Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(3):o151-o153
In the title compound, 2‐amino‐7‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐3,7‐dihydropyrrolo[2,3‐d]pyrimidin‐4‐one, C11H14N4O4, the N‐glycosylic bond torsion angle, χ, is anti [−106.5 (3)°]. The 2′‐deoxyribofuranosyl moiety adopts the 3T4 (N‐type) conformation, with P = 39.1° and τm = 40.3°. The conformation around the exocyclic C—C bond is ap (trans), with a torsion angle, γ, of −173.8 (3)°. The nucleoside forms a hydrogen‐bonded network, leading to a close‐packed multiple‐layer structure with a head‐to‐head arrangement of the bases. The nucleobase interplanar O=C—C⋯NH2 distance is 3.441 (1) Å. 相似文献
7.
Simone Budow Khalil I. Shaikh Henning Eickmeier Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(5):o246-o248
In the title compound, 2′‐deoxy‐7‐propynyl‐7‐deazaadenosine, C14H16N4O3, the torsion angle of the N‐glycosylic bond is anti [χ = −130.7 (2)°]. The sugar pucker of the 2′‐deoxyribofuranosyl moiety is C2′‐endo–C3′‐exo, 2T3 (S‐type), with P = 185.9 (2)° and τm = 39.1 (1)°, and the orientation of the exocyclic C4′—C5′ bond is −ap (trans). The 7‐substituted propynyl group is nearly coplanar with the heterocyclic base moiety. Molecules of the nucleoside form a layered network in which the heterocyclic bases are stacked head‐to‐tail with a closest distance of 3.197 (1) Å. The crystal structure of the nucleoside is stabilized by three intermolecular hydrogen bonds of types N—H⋯ O, O—H⋯ N and O—H⋯ O. 相似文献
8.
Simone Budow Henning Eickmeier Hans Reuter Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(12):o645-o648
The title compound, 1‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐5‐(prop‐1‐ynyl)pyrimidin‐2,4(1H,3H)‐dione, C12H14N2O5, shows two conformations in the crystalline state: conformer 1 adopts a C2′‐endo (close to 2E; S‐type) sugar pucker and an anti nucleobase orientation [χ = −134.04 (19)°], while conformer 2 shows an S sugar pucker (twisted C2′‐endo–C3′‐exo), which is accompanied by a different anti base orientation [χ = −162.79 (17)°]. Both molecules show a +sc (gauche, gauche) conformation at the exocyclic C4′—C5′ bond and a coplanar orientation of the propynyl group with respect to the pyrimidine ring. The extended structure is a three‐dimensional hydrogen‐bond network involving intermolecular N—H...O and O—H...O hydrogen bonds. Only O atoms function as H‐atom acceptor sites. 相似文献
9.
Frank Seela Padmaja Chittepu Junlin He Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(12):o884-o886
In the title compound, 2‐(2‐deoxy‐2‐fluoro‐β‐d ‐arabinofuranosyl)‐1,2,4‐triazine‐3,5(2H,4H)‐dione, C8H10FN3O5, the torsion angle of the N‐glycosylic bond is anti [χ = −125.37 (13)°]. The furanose moiety adopts the N‐type sugar pucker (3T2), with P = 359.2° and τm = 31.4°. The conformation around the C4′—C5′ bond is antiperiplanar (trans), with a torsion angle γ of 177.00 (11)°. A network is formed via hydrogen bonds from the nucleobases to the sugar residues, as well as through hydrogen bonds between the sugar moieties. 相似文献
10.
Frank Seela Helmut Rosemeyer Alexander Melenewski Eva‐Maria Heithoff Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o142-o144
In the monohydrate of 2‐amino‐8‐(2‐deoxy‐α‐d ‐erythro‐pentofuranosyl)‐8H‐imidazo[1,2‐a][1,3,5]triazin‐4‐one, C10H13N5O4·H2O, denoted (I) or αZd, the conformation of the N‐glycosylic bond is in the high‐anti range [χ = 87.5 (3)°]. The 2′‐deoxyribofuranose moiety adopts a C2′‐endo,C3′‐exo(2′T3′) sugar puckering (S‐type sugar) and the conformation at the C4′—C5′ bond is ?sc (trans). 相似文献
11.
Frank Seela Khalil Shaikh Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):o489-o491
The title compound, C14H16N4O4, adopts the anti conformation at the glycosylic bond [χ−117.1 (5)°]. The sugar pucker of the 2′‐deoxyribofuranosyl moiety is C2′‐endo–C3′‐exo, 2T3 (S‐type). The orientation of the exocyclic C4′—C5′ bond is +sc (gauche). The propynyl group is linear and coplanar with the nucleobase moiety. The structure of the compound is stabilized by several hydrogen bonds (N—H⋯O and O—H⋯O), leading to the formation of a multi‐layered network. The nucleobases, as well as the propynyl groups, are stacked. This stacking might cause the extraordinary stability of DNA duplexes containing this compound. 相似文献
12.
Frank Seela Anup M. Jawalekar Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o387-o389
In the title compound, C12H13N3O5, the conformation of the glycosylic bond is anti [torsion angle = −105.3 (2)°]. The 2′‐deoxyribofuranose moiety adopts an S‐type sugar pucker and the orientation of the exocyclic C—C bond is −sc (trans). 相似文献
13.
Frank Seela Yang He Hans Reuter Eva‐Maria Heithoff 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):989-991
In the title compound, 2‐amino‐1‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐5‐methylpyrimidin‐4(1H)‐one, C10H15N3O4, the conformation of the N‐glycosidic bond is syn and the 2‐deoxyribofuranose moiety adopts an unusual OT1 sugar pucker. The orientation of the exocyclic C4′—C5′ bond is +sc (+gauche). 相似文献
14.
Frank Seela Simone Budow Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(1):o54-o57
The title compound, 4‐amino‐1‐(2‐deoxy‐β‐d ‐erythropentofuranosyl)‐5‐(prop‐1‐ynyl)pyrimidin‐2(1H)‐one, C12H15N3O4, shows two conformations in the crystalline state which differ mainly in the glycosylic bond torsion angle and the sugar pucker. Both molecules exhibit an anti glycosylic bond conformation, with torsion angles χ = −135.0 (2) and −156.4 (2)° for molecules 1 and 2, respectively. The sugar moieties show a twisted C2′‐endo sugar pucker (S‐type), with P = 173.3 and 192.5° for molecules 1 and 2, respectively. The crystal structure is characterized by a three‐dimensional network that is stabilized by several intermolecular hydrogen bonds between the two conformers. 相似文献
15.
Junlin He Frank Seela Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(10):o593-o595
In the title regioisomeric nucleosides, alternatively called 1‐(2‐deoxy‐β‐d ‐erythro‐furanosyl)‐1H‐pyrazolo[3,4‐d]pyrimidine, C10H12N4O3, (II), and 2‐(2‐deoxy‐β‐d ‐erythro‐furanosyl)‐2H‐pyrazolo[3,4‐d]pyrimidine, C10H12N4O3, (III), the conformations of the glycosylic bonds are anti [?100.4 (2)° for (II) and 15.0 (2)° for (III)]. Both nucleosides adopt an S‐type sugar pucker, which is C2′‐endo‐C3′‐exo (2T3) for (II) and 3′‐exo (between 3E and 4T3) for (III). 相似文献
16.
Frank Seela Anup M. Jawalekar Simone Budow Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(9):o562-o564
In the title compound, 4‐amino‐1‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐6‐methylsulfanyl‐1H‐pyrazolo[3,4‐d]pyrimidine, C11H16N5O3S, the conformation of the glycosidic bond is between anti and high anti. The 2′‐deoxyribofuranosyl moiety adopts the C3′‐exo–C4′‐endo conformation (3T4, S‐type sugar pucker), and the conformation at the exocyclic C—C bond is +sc (+gauche). The exocyclic 6‐amine group and the 2‐methylsulfanyl group lie on different sides of the heterocyclic ring system. The molecules form a three‐dimensional hydrogen‐bonded network that is stabilized by O—H⋯N, N—H⋯O and C—H⋯O hydrogen bonds. 相似文献
17.
Frank Seela Matthias Zulauf Hans Reuter Guido Kastner 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):489-491
The isomorphous structures of the title molecules, 4‐amino‐1‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐3‐iodo‐1H‐pyrazolo‐[3,4‐d]pyrimidine, (I), C10H12IN5O3, and 4‐amino‐3‐bromo‐1‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐1H‐pyrazolo[3,4‐d]pyrimidine, (II), C10H12BrN5O3, have been determined. The sugar puckering of both compounds is C1′‐endo (1′E). The N‐glycosidic bond torsion angle χ1 is in the high‐anti range [?73.2 (4)° for (I) and ?74.1 (4)° for (II)] and the crystal structure is stabilized by hydrogen bonds. 相似文献
18.
Frank Seela Padmaja Chittepu Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):o231-o233
The title compound, C11H12F2N4O3, exhibits an anti glycosylic bond conformation, with a torsion angle χ = −117.8 (2)°. The sugar pucker is N‐type (C4′‐exo, between 3T4 and E4, with P = 45.3° and τm = 41.3°). The conformation around the exocyclic C—C bond is −ap (trans), with a torsion angle γ = −177.46 (15)°. The nucleobases are stacked head‐to‐head. The crystal structure is characterized by a three‐dimensional hydrogen‐bond network involving N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds. 相似文献
19.
Frank Seela Ping Ding Peter Leonard Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(3):o111-o114
The title compound [systematic name: 7‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐7H‐imidazo[1,2‐c]pyrrolo[2,3‐d]pyrimidine hemihydrate], 2C13H14N4O3·H2O or (I)·0.5H2O, shows two similar conformations in the asymmetric unit. These two conformers are connected through one water molecule by hydrogen bonds. The N‐glycosylic bonds of both conformers show an almost identical anti conformation with χ = −107.7 (2)° for conformer (I‐1) and −107.0 (2)° for conformer (I‐2). The sugar moiety adopts an unusual N‐type (C3′‐endo) sugar pucker for 2′‐deoxyribonucleosides, with P = 36.8 (2)° and τm = 40.6 (1)° for conformer (I‐1), and P = 34.5 (2)° and τm = 41.4 (1)° for conformer (I‐2). Both conformers and the solvent molecule participate in the formation of a three‐dimensional pattern with a `chain'‐like arrangement of the conformers. The structure is stabilized by intermolecular O—H...O and O—H...N hydrogen bonds, together with weak C—H...O contacts. 相似文献
20.
Frank Seela Hui Mei Hai Xiong Simone Budow Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(10):o395-o398
The title compound [systematic name: 4‐amino‐1‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐5‐ethynylpyrimidin‐2(1H)‐one], C11H13N3O4, shows two conformations in the crystalline state. The N‐glycosylic bonds of both conformers adopt similar conformations, with χ = −149.2 (1)° for conformer (I‐1) and −151.4 (1)° for conformer (I‐2), both in the anti range. The sugar residue of (I‐1) shows a C2′‐endo envelope conformation (2E, S‐type), with P = 164.7 (1)° and τm = 36.9 (1)°, while (I‐2) shows a major C3′‐exo sugar pucker (C3′‐exo‐C2′‐endo, 3T2, S‐type), with P = 189.2 (1)° and τm = 33.3 (1)°. Both conformers participate in the formation of a layered three‐dimensional crystal structure with a chain‐like arrangement of the conformers. The ethynyl groups do not participate in hydrogen bonding, but are arranged in proximal positions. 相似文献