Molecular conformational analysis, vibrational spectra, NBO, NLO, HOMO-LUMO and molecular docking studies of ethyl 3-(E)-(anthracen-9-yl)prop-2-enoate based on density functional theory calculations.

FT-IR and FT-Raman spectra of ethyl 3-(E)-(anthracen-9-yl)prop-2-enoate were recorded and analyzed. The conformational behavior of the molecule was also investigated. The vibrational wavenumbers were calculated using DFT quantum chemical calculations. The data obtained from the wavenumber calculations were used to assign vibrational bands obtained experimentally. The geometrical parameters are in agreement with XRD data. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis were used to determine the charge transfer within the molecule and quantum chemical parameters related to the title compound. From the MEP analysis, it is clear that the negative electrostatic potential regions are mainly localized over the carbonyl groups and anthracene ring and are possible sites for electrophilic attack and the positive regions are localized at all the hydrogen atoms as possible sites for nucleophilic attack. NLO and NMR studies are also reported. Molecular docking studies suggest that the title compound might exhibit inhibitory activity against IDE and may act as an insulysin inhibitor. Conformational analysis is also reported.

Crystal structure of 3-(2,5-di-meth-oxy-phen-yl)propionic acid.

In the crystal of the title compound, C11H14O4, the aromatic ring is almost coplanar with the 2-position meth-oxy group with which it subtends a dihedral of 0.54 (2)°, while the 5-position meth-oxy group makes a corresponding dihedral angle of just 5.30 (2)°. The angle between the mean planes of the aromatic ring and the propionic acid group is 78.56 (2)°. The fully extended propionic side chain is in a trans configuration with a C-C-C-C torsion angle of -172.25 (7)°. In the crystal, hydrogen bonding is limited to dimer formation via R 2 (2)(8) rings. The hydrogen-bonded dimers are stacked along the b axis. The average planes of the two benzene rings in a dimer are parallel to each other, but at an offset of 4.31 (2) Å. Within neighbouring dimers along the [101] direction, the average mol-ecular benzene planes are almost perpendicular to each other, with a dihedral angle of 85.33 (2)°.

Crystal structure of cholest-5-en-3ß-yl 3-(2,4-dimeth-oxy-3-methyl-phen-yl)prop-2-enoate.

In the title compound, C39H58O4, the steroid rings A and C adopt a chair conformation, while ring B adopts a half-chair conformation, and ring D has an envelope conformation, with the methyl-substituted C atom as the flap. In the crystal, mol-ecules pack within layers parallel to (100), with their long axis parallel to the [101] direction. Adjacent layers are linked via C-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming a three-dimensional framework.

Crystal structure of (1Z,2E)-cinnamaldehyde oxime.

The title compound, C9H9NO, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. The conformation of the two mol-ecules differs slightly with the phenyl ring in mol-ecule A, forming a dihedral angle of 15.38 (12)° with the oxime group (O-N=C), compared to the corresponding angle of 26.29 (11)° in mol-ecule B. In the crystal, the A and B mol-ecules are linked head-to-head by O-H⋯N hydrogen bonds, forming -A-B-A-B- zigzag chains along [010]. Within the chains and between neighbouring chains there are C-H⋯π inter-actions present, forming a three-dimensional structure.

Crystal structure of 2-pentyl-oxybenzamide.

In the title mol-ecule, C12H17NO2, the amide NH2 group is oriented toward the pent-yloxy substituent and an intra-molecular N-H⋯O hydrogen bond is formed with the pent-yloxy O atom. The benzene ring forms dihedral angles of 2.93 (2) and 5.60 (2)° with the amide group and the pent-yloxy group mean planes, respectively. In the crystal, mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, forming inversion dimers with their mol-ecular planes parallel, but at an offset of 0.45 (1) Što each other. These dimers are ordered into two types of symmetry-related columns extended along the a axis, 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 linked via C-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming a three-dimensional framework structure.

Fluoren-9-one oxime.

In the title mol-ecule, C13H9NO, the fluorene system and the oxime group non-H atoms are essentially coplanar, with a maximum deviation from the fluorene mean plane of 0.079 (2) Šfor the oxime O atom. A short intra-molecular C-H⋯O generates an S(6) ring. In the crystal, mol-ecules related by a twofold screw axis are connected by O-H⋯N hydrogen bonds, forming [100] chains Within these chains, mol-ecules related by a unit translation along [100] show π-π stacking inter-actions between their fluorene ring systems with an inter-planar distance of 3.347 (2) Å. The dihedral angle between the fluorene units of adjacent mol-ecules along the helix is 88.40 (2)°. There is a short C-H⋯π contact between the fluorene groups belonging to neighbouring chains.

(E)-Methyl 3-(10-bromo-anthracen-9-yl)acrylate.

In the title mol-ecule, C18H13BrO2, the anthracene unit forms an angle of 46.91 (2)° with the mean plane of the methyl acrylate moiety. In the crystal, the mol-ecules arrange themselves into strands parallel to [010] and, due to the crystal symmetry, there are eight strands crossing the unit cell. In each strand, mol-ecules form short C-H⋯O and C-H⋯π contacts and have their anthracene groups parallel to each other. Neighboring strands, related by a c-glide operation, are connected via C-H⋯O inter-actions and form a layer parallel to (100). The arrangement of the acrylate and anthracene groups in the crystal do not allow for [2 + 2] or [4 + 4] cyclo-addition.

Ethyl (E)-3-(anthracen-9-yl)prop-2-enoate.

In the asymmetric unit of the title compound, C19H16O2, there are two symmetry-independent mol-ecules (A and B) that differ in the conformation of the ester eth-oxy group. In the crystal, the mol-ecules form inversion dimers via pairs of C-H⋯O inter-actions. Within the dimers, the anthracenyl units have inter-planar distances of 0.528 (2) and 0.479 (2) Šfor dimers of mol-ecules A and B, respectively. Another short C-H⋯O contact between symmetry-independent dimers links them into columns parallel to [10-1]. These columns are arranged into (111) layers and there are π-π stacking inter-actions [centroid-centroid distances = 3.6446 (15) and 3.6531 (15) Å] between the anthracenyl units from the neighbouring columns. In addition, there are C-H⋯π inter-actions between the anthracenyl unit of dimers A and dimers B within the same column.

2,5-Di-meth-oxy-benzo-nitrile.

In the title mol-ecule, C9H9NO2, the non-H atoms are essentially coplanar with a maximum deviation of 0.027 (2) Šfor the C atom of one of the methyl groups. In the crystal, the mol-ecules are arranged into centrosymmetric pairs via pairs of C-H⋯O and C-H⋯N inter-actions whereas π-π stacking inter-actions between the benzene rings [centroid-centroid distance 3.91001 (15) Å] organize them into polymeric strands propagating along the a-axis direction. There is a step of 0.644 (2) Šbetween the two planar parts of the centrosymmetric pair. In neighboring strands related by the n-glide operation, the aromatic rings are tilted by 29.08 (2)°.

2-propoxybenzamide.

In the title mol-ecule, C(10)H(13)NO(2), the amide -NH(2) group is oriented toward the prop-oxy substituent and an intra-molecular N-H⋯O hydrogen bond is formed between the N-H group and the prop-oxy O atom. The benzene ring forms dihedral angles of 12.41 (2) and 3.26 (2)° with the amide and prop-oxy group mean planes, respectively. In the crystal, N-H⋯O hydrogen bonds order pairs of mol-ecules with their mol-ecular planes parallel, but at an offset of 0.73 (2) Što each other. These pairs are ordered into two types of symmetry-related columns extended along the a axis with the mean plane of a pair in one column approximately parallel to (-122) and in the other to (-1-22). The two planes form dihedral angle of 84.40 (1)°. Overall, in a three-dimensional network, the hydrogen-bonded pairs of mol-ecules are either located in (-1-22) or (-122) layers. In one layer, each pair is involved in four C-H⋯O contacts, twice as a donor and twice as an acceptor. Additionally, there is a short C-H⋯C contact between a benzene C-H group and the amide π-system.

Cholest-5-en-3ß-yl 3-(4-eth-oxy-phen-yl)prop-2-enoate.

In the asymmetric unit of the title compound, C(38)H(56)O(3), there are two symmetry-independent mol-ecules that differ in the rotation angle along the C-O bond between the 3-(4-eth-oxy-phen-yl)prop-2-enoate and cholest-5-en-3ß-yl groups by 169.3 (3)°. In both mol-ecules, steroid ring B adopts a half-chair conformation, rings A and C adopt a chair conformation and ring D exists in an envelope form. The two symmetry-independent mol-ecules pack in the crystal into separate layers parallel to (-102) with their long axis parallel to the [201] direction. Short inter-molecular C-H⋯O and C-H⋯π contacts are observed.

2-(Prop-2-enyloxy)benzamide.

In the title mol-ecule, C(10)H(11)NO(2), the benzene ring forms dihedral angles of 33.15 (2) and 6.20 (2)° with the mean planes of the amide and propen-oxy groups, respectively. The amide -NH(2) group is oriented toward the propen-oxy substituent and forms a weak intra-molecular N-H⋯O hydrogen bond to the propen-oxy O atom. The conformation of the propen-oxy group at the Csp(2)-Csp(3) and Csp(3)-O bonds is synperiplanar and anti-periplanar, respectively. In the crystal, N-H⋯O hydrogen bonds involving the amide groups generate C(4) and R(2) (3)(7) motifs that organize the mol-ecules into tapes along the a-axis direction. There are C-H⋯π inter-actions between the propen-oxy -CH(2) group and the aromatic system of neighboring mol-ecules within the tape. The mean planes of the aromatic ring and the propen-oxy group belonging to mol-ecules located on opposite sites of the tape form an angle of 83.16 (2)°.