Tolyl Rings Research Articles

Structural studies of (2R,3R)-(+)-bis(diphenylphosphino)butane and (R)-(+)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl

Abstract The crystal structures of two chiral phosphanes, ((R,R)-chiraphos = (2R,3R)-(+)-2,3-bis(diphenylphosphino)butane and R-Tol-BINAP = (R)-(+)-2,2′-bis(di-p-tolylphosphino)-1,1′-binaphthyl) are unambiguously determined by X-ray crystallography and reported for the first time. The aim is to understand the structural characteristics and their chiral arrangement of the molecules. The (R,R)-chiraphos structure was solved in the orthorhombic space group P212121 while R-Tol-BINAP was solved in the triclinic space group P1. This set of compounds demonstrates attractive intramolecular phenyl ring interactions involving two terminal phenyl rings in (R,R)-chiraphos, while a terminal tolyl ring and the central binaphthyl ring occurs in R-Tol-BINAP. The crystal structure analyses also revealed that all aromatic units have close C–H⋯arylcentroid weak contacts forming continuous networks of columns and layers in (R,R)-chiraphos and R-Tol-BINAP respectively.

Synthesis and Biological Evaluation of Novel Thiadiazole Derivatives as Antiplatelet Agents.

A novel series of thiadiazole compounds was synthesized through the reaction of thiosemicarbazone intermediates with 2, 3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The antiplatelet activity of the synthesized compounds was evaluated using an aggregation test with adenosine diphosphate (ADP) and arachidonic acid (AA) as platelet aggregation inducers. Among the synthesized analogs, compound 3b exhibited the most potent inhibition of platelet aggregation induced by ADP (half maximal inhibitory concentration [IC50] = 39 ± 11 µM). Molecular docking studies of 3b revealed hydrogen bonds between the nitrogen of the thiadiazole ring and Lys280. The tolyl ring exhibited hydrophobic interactions with Tyr105, similar to the antagonist co-crystallized with P2Y12 (PDB ID: 4NTJ). These compounds have the potential to serve as lead molecules for designing P2Y12 inhibitors.

Crystal structure of 2-[(5-amino-1-tosyl-1H-pyrazol-3-yl)-oxy]-1-(4-meth-oxy-phen-yl)ethan-1-one 1,4-dioxane monosolvate.

In the structure of the title compound, C19H19N3O5S·C4H8O2, the two independent dioxane mol-ecules each display inversion symmetry. The pyrazole ring is approximately parallel to the aromatic ring of the oxy-ethanone group and approximately perpendicular to the tolyl ring of the sulfonyl substituent. An extensive system of classical and 'weak' hydrogen bonds connects the residues to form a layer structure parallel to (201), within which dimeric subunits are conspicuous; neighbouring layers are connected by classical hydrogen bonds to dioxanes and by 'weak' hydrogen bonds from Htol-yl donors.

Crystal structure of 5-(β-d-gluco-pyran-osyl-thio)-N-(4-methyl-phen-yl)-1,3,4-thia-diazol-2-amine.

In the structure of the title compound, C15H19N3O5S2, the bond lengths at the linking sulfur atom are significantly different [1.7473 (17) and 1.811 (2) Å], and the angle at the exocyclic nitro-gen atom is wide at 128.45 (18)°. The inter-planar angle between the tolyl and thia-diazole rings is 9.2 (1)°. The complex hydrogen-bonding pattern, involving five donors and five acceptors, can be broken down into a one-dimensional ribbon parallel to the b axis, involving hydrogen bonds of the sugar residues only, and a two-dimensional layer structure parallel to the ab plane, based on the N-H⋯O and O-H⋯N hydrogen bonds.

5-(4-Fluoro-phen-yl)-1-[4-(4-methyl-phen-yl)thia-zol-2-yl]-3-[4-(prop-2-yn-yloxy)phen-yl]-4,5-di-hydro-1H-pyrazole.

In the title compound, C28H22FN3OS, four rings are almost coplanar, with the fluorophenyl ring substantially twisted. In the extended structure, aromatic π-π stacking inter-actions between the pyrazole ring and the tolyl ring link the mol-ecules into centrosymmetric dimers.

1-(4-Fluorophenyl)-5-methyl-N′-{1-[5-methyl-1-(4-methylphenyl)-1H-1,2,3-triazol-4-yl]ethylidene}-1H-1,2,3-triazole-4-carbohydrazide

The title molecule, C22H21FN8O, comprises fluorophenyl (A), methyltriazolyl (B), methyltriazolyl (C) and tolyl (D) rings. The twist angles between the planes through neighbouring ring pairs A/B, B/C and C/D are 45.0 (1), 9.4 (1) and 43.2 (1)°, respectively. Intermolecular π–π interactions between rings A and C and between B and D propagate the structure in the [010] direction and weak C—H...O interactions also occur.

2-[5-(4-Fluorophenyl)-3-(4-methylphenyl)-4,5-dihydro-1H-pyrazol-1-yl]-4-(5-methyl-1-phenyl-1H-1,2,3-triazol-4-yl)thiazole

The title compound, C28H23FN6S, comprises phenyl (A), triazolyl (B), thiazolyl (C), pyrazoyl (D), tolyl (E) and fluorophenyl (F) rings, with twist angles between neighbouring rings pairs A/B, B/C, C/D, D/E and D/F of 64.6 (1), 11.7 (2), 23.5 (2), 8.2 (2) and 73.3 (1)°, respectively. A short intramolecular C—H...N contact and a weak intermolecular C—H...π interaction occur. The crystal chosen for data collection was found to be an inversion twin.

Tetrathiafulvalene Dimer Merged with a Binuclear Ring of Sn and Sb: Synthesis and Molecular Structures Induced by Heteroatoms

In this study, we describe the synthesis and characterization of dimeric tetrathiafulvalene (TTF) derivatives that are doubly bridged by Sn (1) and Sb (2a) atoms as a new class of organic‐inorganic hybrid compounds able to provide enhanced dimensionality in the solid state. The antimony heterocyclic framework was constructed by a simple Sn–Sb metal exchange reaction of a 1,4‐distannine moiety with p‐tolyl antimony dichloride (p‐tolSbCl2). Compound 2a was obtained in cis and trans forms as a stable configurational isomer. From X‐ray crystallographic analysis, there were three conformational isomers in which the tolyl rings were directed in the endo or exo direction. Crystal packing revealed a supramolecular three‐dimensional network through intermolecular short contacts of Sb···S and Sb···π. These packing forces gave a trans‐2aexo–exo conformation in the crystal, although the theoretical calculations predict its instability compared with other conformers. Cyclic voltammetry (CV) measurements of 1 and cis/trans‐2a revealed two pairs of reversible redox processes corresponding to the formation of TTF/TTF·+ and TTF·+/TTF2+. Furthermore, CV of cis/trans‐2a also revealed the reduction waves derived from the reduction of SbIII. Dicationic and tetracationic species were prepared by chemical oxidation, and their electronic structures were also investigated by electronic spectroscopy.

1-{2-Anilino-4-methyl-5-[5-methyl-1-(4-methylphenyl)-1H-1,2,3-triazole-4-carbonyl]thiophen-3-yl}ethanone

In the title compound, C24H22N4O2S, the dihedral angle between the triazole and thiophene rings is 4.83 (14)°. The dihedral angles between the triazole and tolyl rings and between the thiophene and phenyl rings are 48.42 (16) and 9.23 (13)°, respectively. An intramolecular N—H...O hydrogen bond closes anS(6) loop. In the crystal, molecules are stacked parallel to thea-axis direction with weak π–π interactions between adjacent thiophenyl and triazolyl groups within the stack [centroid–centroid separation = 3.9811 (16) Å].

Crystal structure of 5,15-bis-(4-methyl-phen-yl)-10,20-bis-(4-nitro-phen-yl)porphyrin nitro-benzene disolvate.

The whole mol-ecule of the title porphyrin, C46H32N6O4·2C6H5NO2, which crystallized as a nitro-benzene disolvate, is generated by inversion symmetry. The porphyrin macrocycle is almost planar, the maximum deviation from the mean plane of the non-hydrogen atoms is 0.097 (2) Å. The aryl rings at the meso positions are inclined to this mean plane by 74.84 (6)° for the nitro-phenyl rings and 73.37 (7)° for the tolyl rings. In the crystal, the porphyrin mol-ecules are linked by C-H⋯O hydrogen bonds, forming chains along [100]. The solvent mol-ecules are also linked by C-H⋯O hydrogen bonds, forming chains along [100]. Inter-digitation of the p-tolyl groups along the c axis creates rectangular channels in which the solvent mol-ecules are located.

Oxidation of an o-tolyl phosphine complex of platinum: C-H activation and transcyclometallation

The oxidation of the tri(o-tolyl)phospine complex of the doubly cyloplatinated 2,6-di(4-fluorophenyl)pyridine ligand with the electrophilic oxidant iodobenzenedichloride was studied. Three products were formed in the ratio 15:15:70, and all were identified. The simple cis-dichloro platinum(IV) complex 2 (15%) remained in solution and could be purified and fully characterised. The triply cyclometallated 3 (15%), formed via the activation of a methyl group on a tolyl ring, precipitated from the reaction mixture and could not be redissolved or characterised further. Transcyclometallated 4 (70%), where one of the original cyclometallated aryl rings has exchanged for a cyclometallated phosphine ring, crystallised from the reaction mixture and was characterised crystallographically. Redissolution of 4 gave a new agostic species with the phosphine moving to a less sterically demanding position.

{(3S,5R)-5-(2,4-Difluorophenyl)-5-[(1H-1,2,4-triazol-1-yl)methyl]tetrahydrofuran-3-yl}methyl 4-methylbenzenesulfonate

In the title compound, C21H21F2N3O4S, the tetrahydrofuran ring adopts an envelope conformation with the β-C atom positioned at the flap. The triazole, difluorophenyl and tolyl rings of the various substituents on the tetrahydrofuran ring are inclined at 77.88 (12), 83.81 (10) and 81.00 (10)°, respectively, to the best-fit mean plane through the five atoms of the tetrahydrofuran ring. In the crystal, weak C—H...O and C—H...F hydrogen bonds link the molecules into a three-dimensional structure, with molecules stacked along thea-axis direction.

Crystal structure of 5-(4-meth-oxy-phen-yl)-3-(4-methyl-phen-yl)-4,5-di-hydro-1H-pyrazole-1-carbaldehyde.

In the title compound, C18H18N2O2, the pyrazole ring has a twisted conformation on the CH—CH2 bond. The tolyl ring and the 4-meth­oxy­phenyl ring are inclined to the mean plane of the pyrazole ring by 4.40 (9) and 86.22 (9)°, respectively, while the two aromatic rings are inclined to one another by 88.75 (9)°. In the crystal, mol­ecules are linked via bifurcated C—H⋯(O,O) hydrogen bonds and C—H⋯π inter­actions, forming sheets lying parallel to the ab plane.

Crystal structure of (E)-3-[4-(benzylideneamino)-5-sulfanylidene-3-(p-tolyl)-4,5-dihydro-1H-1,2,4-triazol-1-yl]-3-(4-methoxyphenyl)-1-phenylpropan-1-one

The title compound, C32H28N4O2S, crystallizes as a racemate. In the mol­ecule, the bond-angle sum at the C atom of the sulfanyl­idene entity bound to the triazole ring is 360°, with an annular N—C—N bond angle of 102.6 (2)° and two larger N—C—S angles of 127.3 (2) and 130.1 (2)°. The essentially planar 1,2,4-triazole ring (r.m.s. deviation = 0.013 Å) is nearly perpendicular to the phenylpropanone and methoxyphenyl rings , making dihedral angles of 76.9 (2) and 85.2 (2)°, respectively and subtends dihedral angles of 17.6 (2) and 40.3 (2)° with the tolyl and benzylideneamino rings, respectively. There is no π–π stacking between the mol­ecules. The crystal packing is dominated by weak C—H⋯O and C—H⋯N inter­actions, leading to a three-dimensional network structure. An intra­molecular C—H⋯S inter­action also occurs.

Crystal structure of benzyl 3-(3-methyl-phen-yl)di-thio-carbazate.

In the title compound, C15H16N2S2, the central CN2S2 residue is almost planar (r.m.s. deviation = 0.0354 Å) and forms dihedral angles of 56.02 (4) and 75.52 (4)° with the phenyl and tolyl rings, respectively; the dihedral angle between the aromatic rings is 81.72 (5)°. The conformation about the N—N bond is gauche [C—N—N—C = −117.48 (15)°]. Overall, the mol­ecule has the shape of the letter L. In the crystal packing, supra­molecular chains along the a axis are formed by N—H⋯S(thione) hydrogen bonds whereby the thione S atom accepts two such bonds. The hydrogen bonding leads to alternating edge-shared eight-membered {⋯HNCS}2 and 10-membered {⋯HNNH⋯S}2 synthons. The chains are connected into layers by phen­yl–tolyl C—H⋯π inter­actions; the layers stack along the c axis with no specific inter­actions between them.

Crystal structure of 2-(4-methyl-phen-yl)-4H-1,3-benzo-thia-zine.

In the title compound, C15H13NS, the thia­zine ring adopts a boat conformation. The dihedral angle between the planes of the benzene ring of the benzo­thia­zine unit and the tolyl ring is 19.52 (9)°. In the crystal, mol­ecules are linked by weak C—H⋯π inter­actions into a tape structure along the b-axis direction.

Crystal structure of 2-meth-oxy-2-[(4-methyl-phen-yl)sulfan-yl]-1-phenyl-ethan-1-one.

In the title β-thio­carbonyl compound, C16H16O2S, the carbonyl and meth­oxy O atoms are approximately coplanar [O—C—C—O torsion angle = −18.2 (5)°] and syn to each other, and the tolyl ring is orientated to lie over them. The dihedral angle between the planes of the two rings is 44.03 (16)°. In the crystal, supra­molecular chains are formed along the c axis mediated by C—H⋯O inter­actions involving methine and methyl H atoms as donors, with the carbonyl O atom accepting both bonds; these pack with no specific inter­molecular inter­actions between them.

Synthesis, Molecular and Crystal Structure Analysis of 1-(4-Methylbenzenesulfonyl)indole-3-carbaldehyde and DFT Investigation of Its Rotational Conformers

Two independent molecules that differ in terms of rotation about the central S-N bond comprise the asymmetric unit of the title compound 1. The molecules have a V-shape with the dihedral angles between the fused ring system and benzene ring being 79.08(6)° and 72.83(5)°, respectively. The packing is mostly driven by π···π interactions occurring between the tolyl ring of one molecule and the C6 ring of the indole fused ring system of the other. DFT and IRC calculations for these and related 1-(arylsulfonyl)indole molecules showed that the rotational barrier about the S-N bond between conformers is within the 2.5–5.5 kcal/mol range. Crystal data for C16H13NO3S (1): Mr = 299.33, space group Pna21, a = 19.6152(4) Å, b = 11.2736(4) Å, c = 12.6334(3) Å, V = 2793.67(13) Å3, Z = 8, Z' = 2, R = 0.034.

(3aR*,8bR*)-3a,8b-Dihy-droxy-1-(4-methyl-phen-yl)-2-methyl-sulfanyl-3-nitro-1,8b-di-hydro-indeno-[1,2-b]pyrrol-4(3aH)-one.

The asymmetric unit of the title compound, C19H16N2O5S, contains four independent mol­ecules (A, B, C and D), with two mol­ecules (B and D) displaying disorder in their methyl­sulfanyl groups [occupancy ratios of 0.797 (11):0.203 (11) and 0.85 (2):0.15 (2)]. The nitro groups are twisted slightly out of the planes of the 2-pyrroline rings to which they are bonded with dihedral angles of 10.17 (1), 8.01 (1), 9.44 (1) and 8.87 (1)° in mol­ecules A, B, C and D, respectively. The 2-pyrroline rings are almost orthogonal to the attached tolyl rings, forming dihedral angles of 73.44 (1), 81.21 (1), 88.18 (8) and 73.94 (1)° for mol­ecules A, B, C and D, respectively. A weak intra­molecular O—H⋯O inter­action is observed in mol­ecules B and C. The two hy­droxy groups in each mol­ecule are involved in inter­molecular O—H⋯O hydrogen bonding. In the crystal, mol­ecules are connected via O—H⋯O and C—H⋯O hydrogen bonds, forming a complex three-dimensional network.

ANTIOXIDANT POTENTIAL AND ANTIMICROBIAL SCREENING OF SOME NOVEL IMIDAZOLE DERIVATIVES

Bioactive novel imidazole derivatives have been synthesized under solvent free condition using molecular iodine as the catalyst and they are characterized by NMR spectra, X - ray, mass and CHN analysis. Their antioxidant potential were evaluated using different in vitro antioxidant models namely, DPPH (1,1 diphenyl - 2 - picryl hydroxyl) radical, s uperoxide anion and hydroxyl radical scavenging activities. The p - tolyl ring at C - 3 and p - fluorophenyl at C - 2 of the imidazole ring has maximum OH • (fpdmti) when compared with other imidazole derivatives. The low IC 50 value may be due to the electron donat ing (+I effect) ability exerted by the methyl substituent and electron withdrawing ( - I effect) ability exerted by the fluoro substituent. The 3,5 - dimethylphenyl ring at C - 2 of the imidazole ring (dmmppi) has maximum DPPH • and superoxide anion radical scave nging activities when compared with other imidazole derivatives and the low IC 50 value of dmmppi) may be due to the electron donating (+I effect) ability exerted by the two methyl substituent’s. Their antibacterial screening against Staphylococcus aureus , Escherichia coli and Klbesiella pneumoniae and antifungal activity against Aspergillus Niger, Aspergillus flavus and Candida - 6 were also evaluated.