12 research outputs found
Crystal structure of methyl ( Z )-2-[( Z )-3-methyl-2-({( E )-1-[( R *)-4-methylcyclohex-3-en-1-yl]ethylidene}hydrazinylidene)-4-oxothiazolidin-5-ylidene]acetate
International audienceThe new title 4-thiaÂzolidinone derivative, C16H21N3O3S, was obtained from the cyclization reaction of 4-methyl-3-thioÂsemicarbazone and dimethyl acetylÂenediÂcarboxylÂate (DMAD). The cycloÂhexylÂidene ring has an envelope conformation with the stereogenic centre C atom as the flap. Its mean plane makes a dihedral angle of 56.23 (9)° with the thiaÂzolidine ring mean plane. In the crystal, molÂecules are linked by C—HO hydrogen bonds forming chains propagating in the [001] direction. Within the chains there are offset π–π interÂactions between the thiaÂzolidine rings of inversion-related molÂecules [centroid–centroid distance = 3.703 (1) Å]. The chains are linked by further C—HO hydrogen bonds, forming slabs parallel to the ac plane
(3a R ,6 R )-3,3,6-Trimethyl-3,3a,4,5,6,7-hexahydro-2 H -indazole-2-carbothioamide
International audienceThe title compound, C11H19N3S, was prepared by the reaction of (R)-pulegone with thioÂsemicarbazide in acidic medium, using ethanol as solvent. The molÂecule is built up from fused six and five-membered rings. The six-membered ring adopts a chair conformation, while the five-membered ring displays an envelope conformation with the dimethyl-substituted C atom as the flap. The dihedral angle between the mean planes of the two rings is 20.35 (6)°. In the crystal, molÂecules are linked by N-HN and N-HS hydrogen bonds into chains running parallel to [100]
Crystal structure of (4bS,8aR)-1-isopropyl-4b,8,8-trimethyl-7-oxo-4b,7,8,8a,9,10-hexahydrophenanthren-2-yl acetate
The title compound, C22H28O3, was prepared by a direct acetylation reaction of naturally occurring totarolenone. The molecule contains three fused rings, which exhibit different conformations. The central ring has a half-chair conformation, while the non-aromatic oxo-substituted ring has a screw-boat conformation. In the crystal, molecules are linked by C—H...O hydrogen bonds and C—H...π interactions, forming sheets parallel to the bc plane. The carbonyl O atoms and the C atom at the 6-position of the cyclohexene ring are each disordered over two sets of sites with major occupancy components of 0.63 (7) and 0.793 (14), respectively
Crystal structure of 2-[(3aS,6R)-3,3,6-trimethyl-3,3a,4,5,6,7-hexahydro-2H-indazol-2-yl]thiazol-4(5H)-one
The title compound, C13H19N3OS, is a new thiazolidin-4-one derivative prepared and isolated as the pure (3aS,6R)-diastereisomer from (R)-thiosemicarbazone pulegone. It crystallized with two independent molecules (A and B) in the asymmetric unit. The compound is composed of a hexhydroindazole ring system (viz. a five-membered dihydropyrazole ring fused to a cyclohexyl ring) with a thiazole-4-one ring system attached to one of the pyrazole N atoms (at position 2). The overall geometry of the two molecules differs slightly, with the mean planes of the pyrazole and thiazole rings being inclined to one another by 10.4 (1)° in molecule A and 0.9 (1)° in molecule B. In the crystal, the A and B molecules are linked via C—H...O hydrogen bonds, forming slabs parallel to the ab plane. There are C—H...π interactions present within the layers, and between the layers, so forming a three-dimensional structure
Crystal structure of dimethyl 2-((2 Z ,5 Z )-5-(2-methoxy-2-oxoethylidene)-2-{( E )-[2-methyl-5-(prop-1-en-2-yl)cyclohex-2-enylidene]hydrazinylidene}-4-oxothiazolidin-3-yl)fumarate
International audienceThe crystal structure and the conformation of the title compound, C22H27N3O7S, were determined from the synthetic pathway and by X-ray analysis. This compound is a new 4-thiazolidinone derivative prepared and isolated as pure product from thiosemicarbazone carvone. The molecule is built up from an oxothiazolidine ring tetrasubstituted by a methoxy-oxoethylidene, a maleate, an oxygen and a cyclohexylidene-hydrazone. The cyclohexylidene ring is statistically disordered over two positions, resulting in an inversion of configuration for the substituted carbon
New polysubstituted monoterpenic thiazolidinones: synthesis, spectroscopic and crystal structure studies
International audienceThe synthesis of three new polysubstituted monoterpenic thiazolidin-4-ones, namely (Z)-3-methyl-2-{(E)-[(1R,4R)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene]hydrazinylidene}thiazolidin-4-one, C14H21N3OS (2), (2Z,5Z)-5-[(dimethylamino)methylidene]-2-{(E)-[(1R,4R)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene]hydrazinylidene}thiazolidin-4-one, C16H24N4OS (3), and (2Z,5Z)-5-[(dimethylamino)methylidene]-3-methyl-2-{(E)-[(1R,4R)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene]hydrazinylidene}thiazolidin-4-one, C17H26N4OS (4), is reported, starting from the corresponding thiosemicarbazones obtained from naturally occurring (R)-camphor. All the newly obtained thiazolidin-4-ones have been fully characterized by HRMS and 1H and 13C (1D and 2D) NMR spectroscopy. Two of them, i.e. 2 and 3, were identified by single-crystal X-ray crystallography, confirming the synthetic pathway and the spectroscopic analyses. In 3, there are two roughly identical molecules within the asymmetric unit with the same absolute configuration. These two molecules are linked through N-H...O hydrogen bonds, building an R22(8) graph-set motif
Synthesis of a Series of Chalcones and Related Flavones and Evaluation of their Antibacterial and Antifungal Activities
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New 1,2,3-Triazoles from (R)-Carvone: Synthesis, DFT Mechanistic Study and In Vitro Cytotoxic Evaluation
Aseries of novel 1,4-disubstituted 1,2,3-triazoles were synthesized from an (R)-carvone terminal alkyne derivative via a Cu (I)-catalyzed azide–alkyne cycloaddition reaction using CuSO4,5H2O as the copper (II) source and sodium ascorbate as a reducing agent which reduces Cu (II) into Cu (I). All the newly synthesized 1,2,3-triazoles 9a–h were fully identified on the basis of their HRMS and NMR spectral data and then evaluated for their cell growth inhibition potential by MTS assay against HT-1080 fibrosarcoma, A-549 lung carcinoma, and two breast adenocarcinoma (MCF-7 and MDA-MB-231) cell lines. Compound 9d showed notable cytotoxic effects against the HT-1080 and MCF-7 cells with IC50 values of 25.77 and 27.89 µM, respectively, while compound 9c displayed significant activity against MCF-7 cells with an IC50 value of 25.03 µM. Density functional calculations at the B3LYP/6-31G* level of theory were used to confirm the high reactivity of the terminal alkyne as a dipolarophile. Quantum calculations were also used to investigate the mechanism of both the uncatalyzed and copper (I)-catalyzed azide–alkyne cycloaddition reaction (CuAAC). The catalyzed reaction gives complete regioselectivity via a stepwise mechanism streamlining experimental observations. The calculated free-energy barriers 4.33 kcal/mol and 29.35 kcal/mol for the 1,4- and 1,5-regioisomers, respectively, explain the marked regioselectivity of the CuAAC reaction
Diastereoselective synthesis and cytotoxic evaluation of new isoxazoles and pyrazoles with monoterpenic skeleton
International audienceNew series of chiral isoxazoles and pyrazoles with monoterpenic skeleton, have been efficiently synthesized from naturally occurring (R)-Carvone, using 1,3-dipolar cycloaddition reaction with arylonitrile oxides and diarylnitrilimines. The reaction showed high peri-, and regioselectivity. In the case of diarylnitrilimines, the reaction revealed to be highly diastereoselective. The structure of the newly synthesized adducts were fully established via spectroscopic analysis and X-ray crystallography. A succinct theoretical study was used to explain the diastereoselectivity experimentally observed. All the newly synthesized monoterpenic isoxazole and pyrazole derivatives were evaluated for their cytotoxic activity against human HT1080, MCF-7 and A-549 cancer cells