Search results for " Chemistry"
showing 10 items of 41321 documents
Packing incentives and a reliable N–H⋯N–pyridine synthon in co-crystallization of bipyridines with two agrochemical actives
2011
The co-crystallization of agrochemical actives thiophanate-methyl and thiophanate-ethyl with 2,2′-bipyridine, 4,4′-bipyridine and 1,2-bis(4-pyridyl)ethane was investigated with conventional crystallization, the slurry method and liquid-assisted grinding. Co-crystals of both thiophanates with all bipyridines were found and the structures solved with single crystal X-ray diffraction. Whereas the 2,2′-bipyridine co-crystals seem to form because of a combination of weak interactions, and in the case of the thiophanate-methyl, partly because of close packing incentives, the 4,4′-bipyridine and 1,2-bis(4-pyridyl)ethane co-crystals form mainly because of a favourable N–H···N–pyridine hydrogen bond…
N,N-Dimethyl-N-propylpropan-1-aminium chloride monohydrate
2008
The title compound, C8H20N+·Cl−·H2O, has been prepared by a simple one-pot synthesis route followed by anion exchange using resin. In the crystal structure, the cations are packed in such a way that channels exist parallel to the b axis. These channels are filled by the anions and water molecules, which interact via O—H...Cl hydrogen bonds [O...Cl = 3.285 (3) and 3.239 (3) Å] to form helical chains. The cations are involved in weak intermolecular C—H...Cl and C—H...O hydrogen bonds. The title compound is not isomorphous with the bromo or iodo analogues.
3,4,5-Trimethoxy-4'-methylbiphenyl
2013
In the title compound, C16H18O3, the dihedral angle between the benzene rings is 33.4 (2)°. In the crystal, molecules are packed in a zigzag arrangement along the b-axis and are interconnected via weak C—H⋯O hydrogen bonds, and C—H⋯π interactions involving the methoxy groups and the benzene rings of neighbouring molecules.
3,5-Dimethoxy-4'-methylbiphenyl
2013
The title compound, C15H16O2, crystallizes with three independent molecules in the asymmetric unit. The intramolecular torsion angle between the aromatic rings of each molecule are −36.4 (3), 41.3 (3) and −37.8 (3)°. In the crystal, the complicated packing of the molecules forms wave-like layers along the b and c axes. The molecules are connected via extensive methoxy–phenyl C—H…π interactions. A weak C—H…O hydrogen-bonding network also exists between methoxy O atoms and aromatic or methoxy H atoms.
3,4-Dimethoxy-4'-methylbiphenyl
2013
In the title compound, C15H16O2, the dihedral angle between the planes of the aromatic rings is 30.5 (2). In the crystal, molecules are linked via C—HO hydrogen bonds and C— H interactions, forming a two-dimensional network lying parallel to (100). peerReviewed
Methyl 3',5'-dimethoxybiphenyl-4-carboxylate
2013
In the title compound, C16H16O4, the dihedral angle between the benzene rings is 28.9 (2)°. In the crystal, molecules are packed in layers parallel to the b axis in which they are connected via weak intermolecular C-H...O contacts. Face-to-face π-π interactions also exist between the benzene rings of adjacent molecules, with centroid-centroid and plane-to-plane shift distances of 3.8597 (14) and 1.843 (2) Å, respectively.
Methyl 3',4',5'-trimethoxybiphenyl-4-carboxylate
2013
In the title compound, C17H18O5, the dihedral angle between the benzene rings is 31.23 (16)°. In the crystal, the molecules are packed in an antiparallel fashion in layers along the a axis. In each layer, very weak C-H...O hydrogen bonds occur between the methoxy and methyl ester groups. Weak C-H...[pi] interactions between the 4'- and 5'-methoxy groups and neighbouring benzene rings [methoxy-C-ring centroid distances = 4.075 and 3.486 Å, respectively] connect the layers.
1,1,4,4-Tetramethylpiperazinediium dibromide
2009
A small quantity of the title compound, C8H20N22+·2Br−, was formed as a by-product in a reaction between a diamine and an alkyl bromide. The asymmetric unit contains half of a centrosymmetric dication and a bromide anion. In the crystal, weak intermolecular C—H...Br hydrogen bonds consolidate the crystal packing.
The chemical composition of the aerial parts essential oil of Ammi crinitum Guss. (Apiaceae) endemic of Sicily (Italy)
2022
Ammi L. is a small genus of economically important plants belonging to Apiaceae family that includes only six taxa. In the present study the chemical composition of the essential oil from aerial parts of Ammi crinitum Guss., a very rare plant, endemic of Sicily, was analyzed by GC–MS. No previously paper has been published on this species. The results showed the presence of large quantity of monoterpene hydrocarbons with sabinene (63.9%), as the most abundant component. Other metabolites present in good quantity were γ-terpinene (8.0%), and 4-terpineol (3.7%). Based on the composition of the essential oil of all the other Ammi taxa, several considerations have been carried out.
Polyphenols and Pharmacological Screening of a Monarda fistulosa L. dry Extract Based on a Hydrodistilled Residue By-Product
2021
This study aimed to determine the composition and content of polyphenols in the dry extract obtained from the hydrodistilled residue by-product of the wild bergamot (Monarda fistulosa L., Lamiaceae Martinov family) herb (MFDE) and to evaluate its safety and pharmacological properties. The total phenolic content (TPC) in the MFDE was 120.64 mg GAE/g. The high-performance liquid chromatography (HPLC) analysis showed the presence of a plethora of phenolic compounds, including hydroxycinnamic acids and flavone derivatives in the MFDE, with rosmarinic acid and luteolin-7-O-glucoside being the main components. With an IC50 value of 0.285 mg/mL, it was found to be a strong DPPH radical scavenger. …