نتایج جستجو برای: chromene derivatives
تعداد نتایج: 105503 فیلتر نتایج به سال:
Synthesis of minor prenylflavonoids found in hops and their non-natural derivatives were performed. The antiproliferative activity of the obtained compounds against some human cancer cell lines was investigated. Using xanthohumol isolated from spent hops as a lead compound, a series of minor hop prenylflavonoids and synthetic derivatives were obtained by isomerization, cyclisation, oxidative-cy...
In the crystal structure of the title compound, C(15)H(9)FO(3), inversely oriented mol-ecules form inversion dimers through pairs of O-H⋯O hydrogen bonds. The benzene ring is twisted at an angle of 12.0 (1)° relative to the 4H-chromene skeleton of the mol-ecule. Adjacent 4H-chromene units are parallel in a given column or oriented at an angle of 50.0 (1)° in neighboring, inversely oriented, col...
In the title compound, C16H12O4, the substituent benzene ring and meth-oxy group are twisted relative to the 4H-chromene skeleton by 24.1 (1) and 61.3 (1)°, respectively. In the crystal, mol-ecules are connected by classical O-H⋯O and weak C-H⋯O hydrogen bonds, forming chains parallel to [201]. The 4H-chromene ring systems of adjacent mol-ecules are either parallel or inclined at an angle of 28...
In the title compound, C13H12Cl N O2S2, the 2H-chromene ring system is almost planar, with a maximum deviation of 0.005 (2) Å. The packing features C-H⋯S hydrogen bonds and π-π inter-actions between fused benzene rings of chromene [shortest centroid-centroid distances = 3.6553 (13) and 3.5551 (13) Å].
The aerial parts of Tephrosia carrollii afforded two chromene chalcones. Their structures and stereochemistry were established by spectroscopic methods. The structure of oaxacacin was revised and confirmed by X-ray diffraction. In this paper, we describe the isolation of the chalcone known as "oaxacacin" and the new chalcone named epoxyobovatachalcone. The compound der. oaxacacin was found to b...
a series of 2-amino-4-(nitroalkyl)-4h-chromene-3-carbonitriles were synthesized by an efficient multicomponent reaction in aqueous media using dbu (1,8-diazabicyclo[5.4.0]undec-7-ene) as a catalyst at room temperature. mild condition, environment friendly procedure and excellent yields are the main advantages of this procedure. the cytotoxic activity of target compounds were evaluated against t...
The problem of bacteria resistance to many known agents has inspired scientists and researchers to discover novel efficient antibacterial drugs. Three rapid, clean, and highly efficient methods were developed for one-pot synthesis of 7-(aryl)-10,10-dimethyl-10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-dione derivatives. Three components are condensed in the synthesis, 4-hydroxycoumarin, 5,5-...
The synthesis of 6H-benzo[c]chromenes from unactivated 2-bromo aryl benzyl ethers was studied through two approaches: (i) the transition-metal-free intramolecular dehydrohalide coupling via intramolecular homolytic aromatic substitution; and (ii) the intramolecular cyclization via direct C–H arylation catalysed by PdCl2(MeCN)2. Having developed the most efficient method, a 17-membered chromene ...
In the title compound, C19H22N2O4, the six-membered cyclo-hexenone ring of the chromene unit adopts an envelope conformation, with the dimethyl-substituted C atom as the flap, while the pyran ring has a boat conformation. These two mean planes are inclined to one another by 6.65 (13)°·The benzene ring is normal to the 4H-chromene moiety mean plane, making a dihedral angle of 89.18 (5)°. The met...
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