scholarly journals 7,7′,8,8′-Tetramethoxy-4,4′-dimethyl-3,5′-bichromene-2,2′-dione

2009 ◽  
Vol 65 (6) ◽  
pp. o1322-o1323 ◽  
Author(s):  
Hoong-Kun Fun ◽  
Samuel Robinson Jebas ◽  
Mehtab Parveen ◽  
Zakia Khanam ◽  
Raza Murad Ghalib

In the title molecule, C24H22O8, the mean planes of the two coumarin units are inclined to each other at a dihedral angle of 79.93 (3)°. The attached methoxy groups form torsion angles of 7.65 (19) and 78.36 (14)° with respect to one coumarin unit, and angles of 9.01 (16) and 99.08 (11)° with respect to the other coumarin unit. In the crystal structure, weak intermolecular C—H...O hydrogen bonds connect pairs of molecules to form dimers, generatingR22(16) andR22(18) rings; the dimers are linked by further weak intermolecular C—H...O hydrogen bonds, forming extended chains. Additional stabilization is provided by weak C—H...π interactions.

2015 ◽  
Vol 71 (12) ◽  
pp. o935-o936 ◽  
Author(s):  
Hazem Bouraoui ◽  
Ali Boudjada ◽  
Noudjoud Hamdouni ◽  
Youcef Mechehoud ◽  
Jean Meinnel

In the title molecule, C16H12Cl2O2Se, the C—Se—C angle is 100.05 (14)°, with the dihedral angle between the planes of the benzene rings being 69.92 (17)°. The average endocyclic angles (Se—Car—Car; ar = aromatic) facing the Se atom are 120.0 (3) and 119.4 (3)°. The Se atom is essentially coplanar with the benzene rings, with Se—Car—Car—Cartorsion angles of −179.2 (3) and −179.7 (3)°. In the crystal, molecules are linkedviaC—H...O hydrogen bonds forming chains propagating along thea-axis direction. The chains are linkedviaC—H...π interactions, forming a three-dimensional network.


Author(s):  
Qi-Di Zhong ◽  
Sheng-Quan Hu ◽  
Hong Yan

In the title compound, C13H12N2O2(I), the mean planes of the pyrrole and benzyl rings are approximately perpendicular, forming a dihedral angle of 87.07 (4) °. There is an intramolecular N—H...O hydrogen bond forming an S(7) ring motif. In the crystal, molecules are linkedviaa pair of N—H...O hydrogen bonds forming inversion dimers. C—H...O hydrogen bonds link the dimers into chains along direction [10-1]. The chains are further linked by weak C—H...π interactions forming layers parallel to theacplane.


2015 ◽  
Vol 71 (10) ◽  
pp. 1140-1142 ◽  
Author(s):  
Hong-Shun Sun ◽  
Yu-long Li ◽  
Hong Jiang ◽  
Ning Xu ◽  
Hong Xu

In the title compound, C27H21FN2O4, the mean planes of the indole ring systems (r.m.s. deviations = 0.0263 and 0.0160 Å) are approximately perpendicular to one another, making a dihedral angle of 84.0 (5)°; the fluorobenzene ring is twisted with respect to the mean planes of the two indole ring systems at 89.5 (5) and 84.6 (3)°. In the crystal, pairs of N—H...O hydrogen bonds link the molecules into inversion dimers, which are further linked by N—H...O hydrogen bonds into supramolecular chains propagated along theb-axis direction. Weak C—H...π interactions are observed between neighbouring chains.


Author(s):  
S. Samundeeswari ◽  
Manohar V. Kulkarni ◽  
G. N. Anil Kumar

The title compound, C21H14N2O2, was prepared by Pictet–Spengler cyclization of tryptamine and 4-formyl coumarin. In the molecule, the dihedral angle between the mean planes of the coumarin and β-carboline ring systems is 63.8 (2)°. In the crystal, molecules are linkedviaN—H...N hydrogen bonds, forming chains along theb-axis direction. Within the chains, there are a number of offset π–π interactions present [shortest intercentroid distance = 3.457 (2) Å].


2009 ◽  
Vol 65 (6) ◽  
pp. o1265-o1265
Author(s):  
M. Khawar Rauf ◽  
Michael Bolte ◽  
Amin Badshah

In the title molecule, C13H16ClNO, the mean plane of the atoms in the –CONH– group forms a dihedral angle of 42.0 (4)° with the benzene ring plane. In the crystal structure, molecules are linked by intermolecular N—H...O hydrogen bonds, generatingC(4) chains along [100].


2012 ◽  
Vol 68 (6) ◽  
pp. o1970-o1971 ◽  
Author(s):  
Sana Aslam ◽  
Hamid Latif Siddiqui ◽  
Matloob Ahmad ◽  
Muhammad Zia-ur-Rehman ◽  
Masood Parvez

In the title molecule, C13H13N3O4S, the heterocyclic thiazine ring adopts a half-chair conformation in which the S and an adjacent C atom are displaced by 0.919 (3) and 0.300 (4) Å, respectively, on the same side of the mean plane formed by the remaining ring atoms. The mean planes of the benzene and pyrazole rings are inclined at a dihedral angle of 18.32 (12)° with respect to each other. The acetate group is oriented at 80.75 (8)° with respect to the pyrazole ring. The crystal structure is stabilized by O—H...N and C—H...O hydrogen bonds, resulting in fused eight- and seven-membered rings with R 2 2(8) and R 2 2(7) graph-set motifs, respectively.


2012 ◽  
Vol 68 (8) ◽  
pp. o2491-o2491 ◽  
Author(s):  
Hong Dae Choi ◽  
Pil Ja Seo ◽  
Uk Lee

In the title compound, C15H10BrFO2S, the 3-fluorophenyl ring makes a dihedral angle of 85.0 (1)° with the mean plane [r.m.s. deviation = 0.008 (2) Å] of the benzofuran fragment. In the crystal, molecules are linked by weak C—H...O hydrogen bonds and a Br...O contact [3.200 (3) Å]. The crystal structure also exhibits slipped π–π interactions between the benzene and furan rings of neighbouring molecules [centroid–centroid distance = 3.619 (4) Å and slippage of 1.389 (4) Å]. In the 3-fluorophenyl ring, the F atom is disordered over two positions with site-occupancy factors of 0.583 (5) and 0.417 (5).


2015 ◽  
Vol 71 (9) ◽  
pp. o684-o685
Author(s):  
Amal Errossafi ◽  
Abdellatif El Kihel ◽  
Salaheddine Guesmi ◽  
Mohamed Saadi ◽  
Lahcen El Ammari

The reaction of 5-methyl-7-nitro-1H-indole-2-carbohydrazide with ethyl acetoacetate yielded the title molecule, C16H18N4O5, in which the indole ring is almost planar, with the greatest deviation from the mean plane being 0.006 (2) Å. The nine atoms of the indole ring are almost perpendicular to the mean plane through the ethyl acetate group, as indicated by the dihedral angle of 87.02 (4)° between them. In the crystal, centrosymmetric supramolecular dimers are formedviaN—H...O hydrogen bonds and eight-membered amide {...HNCO}2synthons. These are consolidated into a three-dimensional architecture by C—H...O contacts, and by π–π interactions between six-membered rings [inter-centroid distance = 3.499 (2) Å].


2014 ◽  
Vol 70 (10) ◽  
pp. 231-234
Author(s):  
Bernhard Bugenhagen ◽  
Yosef Al Jasem ◽  
Thies Thiemann

In the title molecule, C12H17NO2, the amide NH2group is oriented toward the pentyloxy substituent and an intramolecular N—H...O hydrogen bond is formed with the pentyloxy O atom. The benzene ring forms dihedral angles of 2.93 (2) and 5.60 (2)° with the amide group and the pentyloxy group mean planes, respectively. In the crystal, molecules are linked by pairs of N—H...O hydrogen bonds, forming inversion dimers with their molecular planes parallel, but at an offset of 0.45 (1) Å to each other. These dimers are ordered into two types of symmetry-related columns extended along theaaxis, with the mean plane of one set of dimers in a column approximately parallel to (121) and the other in a column approximately parallel to (1-21). The two planes form a dihedral angle of 85.31 (2)°, and are linkedviaC—H...O hydrogen bonds and C—H...π interactions, forming a three-dimensional framework structure.


2012 ◽  
Vol 68 (8) ◽  
pp. o2440-o2440
Author(s):  
Augusto Rivera ◽  
Diego Quiroga ◽  
Jaime Ríos-Motta ◽  
Michal Dušek ◽  
Karla Fejfarová

The title compound, C3H6N4O2, exhibits partial disorder with the refined occupancy ratios of the two components being 0.582 (5):0.418 (5). In the major component, the nitroso groups have a relativesynspatial arrangement [O=N...N=O pseudo-torsion angle = 1.1 (4)°], whereas the other component has anantidisposition [177.6 (1)°]. The N—N=O moieties are almost coplanar with a dihedral angle of 5.3 (3)°, while in the minor occupied set of atoms, this angle is 8 (1)°. In both components, the imidazolidine ring adopts a twisted conformation on the C—C bond and the crystal structure shows the strain of this ring according to the N—CH2—CH2—N torsion angles [25.9 (5) and −23.8 (7)°]. In the crystal, molecules are linked by weak C—H...O hydrogen bonds.


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