Showing papers on "Benzopyran published in 2003"
TL;DR: In this paper, 1-Benzopyran-4(4H)-one derivatives have been successfully employed as novel activated alkenes in the Baylis-Hillman coupling with heteroaromatic-aldehydes, nitrobenzaldehes and isatin-derivatives and the corresponding adducts, derived from pyridine-2-carboxaldehyde, have been transformed into a novel indolizine-fused-chromone framework.
48 citations
TL;DR: In this paper, 5-hydroxy uracils and 4-hydroxynodes were refluxed with 2-bromobenzyl bromides in acetone in the presence of anhydrous potassium carbonate to afford a number of 5-(2′)-bromogenyloxy) pyrimidine-2,4-dione (80−92%) or 4-(2´bromomethoxy) benzopyran-7-ones (70−82%) respectively.
45 citations
TL;DR: In this paper, the molecular and crystal structure of 2-amino-3-(2-methoxyethoxycarbonyl)-4-(2 -nitrophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo[b]pyran was established by X-ray diffraction analysis.
Abstract: Substituted 2-aminobenzo[b]pyrans were synthesized by three-component condensation of aromatic aldehydes, cyanoacetic acid derivatives, and cyclic 1,3-diketones. The molecular and crystal structure of 2-amino-3-(2-methoxyethoxycarbonyl)-4-(2-nitrophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo[b]pyran was established by X-ray diffraction analysis.
44 citations
TL;DR: A short stereoselective synthesis of (3R)-3,4-dihydro-6,8-dimethoxy-3-undecyl-1H-[2]benzopyran-1-one and derivatives isolated from Ononis natrix has been described as discussed by the authors.
Abstract: A short stereoselective synthesis of (3R)-3,4-dihydro-6,8-dimethoxy-3-undecyl-1H-[2]benzopyran-1-one and derivatives isolated from Ononis natrix has been described. Condensation of dodecanoyl chloride with 3,5-dimethoxyhomophthalic acid afforded 6,8-dimethoxy-3-undecylisocoumarin 3, which, on sequential saponification and esterification, yielded the keto ester 5. Enantioselective reduction of 5 with TarB-NO2/LiBH4 directly furnished the title dihydroisocoumarin 1a in 80% ee (82% yield). Partial as well as complete demethylation of the latter provided the dihydroisocoumarins 1b and 1c, respectively. Diastereotopy of the CH2 H-atoms on either side of the stereogenic center (C(3)) and the mass-fragmentation pattern of the dihydroisocoumarins have also been described. All of the compounds synthesized were examined in vitro for antifungal activity.
42 citations
TL;DR: A series of benzopyran derivatives was synthesized and their insulin-sensitizing activities were evaluated in 3T3-L1 cells, and compounds 6 and 11 exhibited more potent insulin-magnifying activity than rosiglitazone.
39 citations
TL;DR: Compounds 1 and 2 can be regarded as primary antioxidants with radical-scavenging and chain-breaking activities as well as secondary antioxidants with inhibitory effect on radical generation, which were more effective than all the other antioxidants tested.
Abstract: Two antioxidant compounds were isolated from C. sappan L by multiple steps of column chromatography and thin layer chromatography in succession with superoxide scavenging assay as activity monitor. Structures of the two compounds were determined by spectroscopic methods as 1',4'-dihydro-spiro[benzofuran-3(2H),3'-[3H-2]benzopyran]-1',6',6',7'-tetrol (compound 1) and 3-[[4,5-dihydroxy-2(hydroxymethyl) phenyl]-methyl]-2,3-dihydro-3,6-benzofurandiol (compound 2). Characterization of antioxidant properties of these two compounds was done by determining the inhibitory effect on xanthine oxidase activity as well as scavenging effect on superoxide anion and hydroxyl radicals. Our results indicated that compounds 1 and 2 inhibited xanthine oxidase activity and scavenged superoxide anion and hydroxyl radicals. Compounds 1 and 2 possessed similar radical scavenging activities as ascorbic acid, and they were more effective than other well-known antioxidants such as alpha-tocopherol, beta-carotene, and BHT. As inhibitors of free radical formation, compounds 1 and 2 were more effective than all the other antioxidants tested. In conclusion, compounds 1 and 2 can be regarded as primary antioxidants with radical-scavenging and chain-breaking activities as well as secondary antioxidants with inhibitory effect on radical generation.
35 citations
TL;DR: Compounds 4 and 6 will well serve as lead compounds for further studies of the mechanism of action of Aβ-and CTF-induced neuron-cell death, studies which should enhance the future development of new drugs for the prevention and treatment of AD.
35 citations
TL;DR: The solid-phase library construction of 2000 analogues of 6-amino-2,2-dimethyl-3,4,6-trisubstituted-2H-1-benzopyran analogues, obtained in good yields and high purity upon cleavage from the resins, were characterized by LC/MS, HRMS, and (13)C NMR spectroscopy.
Abstract: We report the solid-phase library construction of 2000 analogues of 6-amino-2,2-dimethyl-3,4,6-trisubstituted-2H-1-benzopyran. The polymer-bound hydroxyalkoxychromanes 5, produced by nucleophilic reactions with various alcohols on epoxides generated in situ, served as key intermediates for subsequent diversification. Further reactions on these hydroxyalkoxychromanes 5 with various electrophiles, such as alkyl halides and acid halides, produced the desired 6-amino-2,2-dimethyl-3,4,6-trisubstituted-2H-1-benzopyran analogues 9, 10, and 11. The progress of reactions could be monitored as solid-bound intermediates by ATR-FTIR or HR-MAS-NMR spectroscopy. The final compounds, obtained in good yields and high purity upon cleavage from the resins, were characterized by LC/MS, HRMS, (1)H NMR, and (13)C NMR spectroscopy.
30 citations
TL;DR: The present review discusses the synthetic strategies of new ligands exhibiting mainly 5-HT(1A)binding affinities in the synthesis of compounds structurally related to arylpiperazine, 2-aminotetralin, and benzopyran derivatives.
Abstract: The present review discusses the synthetic strategies of new ligands exhibiting mainly 5-HT1A binding affinities. Specifically we focused our attention in the synthesis of compounds structurally related to arylpiperazine, 2-aminotetralin, and benzopyran derivatives.
29 citations
TL;DR: Two isoflavones containing a sulfur or oxygen hinge with an amine-bearing side chain have been designed and synthesized as potential selective estrogen receptor modulators, and binding affinity data indicate that oxygen hinge is more favorable than sulfur for binding.
29 citations
TL;DR: Enantiomeric purities of the final aminochroman derivatives were determined by capillary electrophoresis using beta-cyclodextrins as a chiral selector.
TL;DR: Biological testing showed a dramatic decrease in activity thus revealing an important site of activity in this class of compounds.
TL;DR: Zn/NH4Cl−mediated reactions of aldehyde with nitro compounds have been studied in this paper, showing that N-alkyl/arylamino)-3-formylchromones can produce 9a-d and 11e-h from 4a−d and 4e−h.
Abstract: Zn/NH4Cl–mediated reactions of aldehyde 1 with nitro compounds 2 afford 2-(N-alkyl/arylamino)-3-formylchromones 4, which on heating with 70% H2SO4 produces 9a-d and 11e-h from 4a-d and 4e-h, respec...
TL;DR: In this paper, a series of new N-chlorobenzopyran-2-imines were prepared in moderate to good yields, by reacting sodium hypochlorite in an acidic medium with benzopyrin-2imines obtained via the Knoevenagel condensation.
TL;DR: A series of 4-(N-imidazol-2-ylmethyl)aminobenzopyran analogues, originally designed as K(ATP) openers for ischemic diseases, showed antiangiogenic properties through the inhibition of HUVEC tube formation.
Patent•
10 Jan 2003
TL;DR: In this article, a method of treating a diabetic condition by administering a therapeutically effective amount of a histamine-3 receptor antagonist, including benzofuran and benzopyran derivatives of formula, was described.
Abstract: The invention relates to a method of treating a diabetic condition by administering a therapeutically effective amount of a histamine-3 receptor antagonist, including benzofuran and benzopyran derivatives of formula (I), aminoalkoxybiphenylcarboxamide compounds of formula (III), and aminoetherbiphenyl compounds of formula (IV) as described herein.
Patent•
30 Jul 2003
TL;DR: In this paper, a benzopyran derivatives substituted with secondary amines including imidazole, their preparation, and pharmaceutical compositions containing them are described. The present invention is pharmacologically useful for the treatment of cancer, rheumatoid arthritis, and diabetic retinopathies through anti-angiogenic properties, and also pharmacological useful in the protection of heart and neuronal cells against ischemia-reperfusion injury or preserving organs.
Abstract: The present invention relates to benzopyran derivatives substituted with secondary amines including imidazole, their preparation, and pharmaceutical compositions containing them. The present invention is pharmacologically useful for the treatment of cancer, rheumatoid arthritis, and diabetic retinopathies through anti-angiogenic properties, and also pharmacologically useful in the protection of heart and neuronal cells against ischemia-reperfusion injury or preserving organs.
TL;DR: From the leaves of Mallotus apelta two new benzopyran compounds (1, 2) were obtained and their structures were determined using spectroscopic methods.
TL;DR: In this article, the Vielsmeyer Haack reaction was used to obtain 4-hydroxy-2-oxo-2H-1-benzopyran-3-aldehyde-semicarbazone.
Patent•
12 Dec 2003
TL;DR: In this paper, novel benzopyran analogs are disclosed and methods for the lowering and controlling of normal or elevated intraocular pressure as well as a method for the treatment of glaucoma using compositions containing one or more of the compounds of the present invention.
Abstract: Novel benzopyran analogs are disclosed. Also disclosed are methods for the lowering and controlling of normal or elevated intraocular pressure as well as a method for the treatment of glaucoma using compositions containing one or more of the compounds of the present invention.
TL;DR: The crystal structure of syn-1-acetyl-9′a-hydro-8′-methoxyspiro [3H-indole-3,2′(2a′H) oxeto [3, 2-g]furo[3, 1]-pyran-2, 6′-dione 1 was determined by X-ray diffraction analysis as discussed by the authors.
Abstract: The crystal structure of syn-1-acetyl-9′a-hydro-8′-methoxyspiro[3H-indole-3,2′(2a′H) oxeto[3,2-g]furo[3,2-g]benzo[ b]pyran-2,6′-dione 1 was determined by X-ray diffraction analysis. It possesses P2(1)/c space group symmetry, with a = 12.391(3), b = 15.035(3), c = 9.5435(19) A, β = 93.66(3)○, and D
calc. = 1.517 Mg/m3 for Z = 4.
TL;DR: An efficient synthesis of the title benzopyranodione derivatives based on a Michael addition/cyclization sequence between 2-(1-hydroxyalkyl)-1,4-benzoquinones and enamines (or an imine) is described in this article.
Abstract: An efficient synthesis of the title benzopyranodione derivatives based on a Michael addition/cyclization sequence between 2-(1-hydroxyalkyl)-1,4-benzoquinones and enamines (or an imine) is described.
TL;DR: In this paper, a highly selective transformation of 5,6,7,8-tetrahydro-2H-1-benzopyran-2,5-diones with hydrazides, arylhydrazines and heterocyclic hydrazines as nitrogen-containing nucleophiles was investigated.
Abstract: A highly selective transformation of 5,6,7,8-tetrahydro-2H-1-benzopyran-2,5-diones (1a-c) with hydrazides, arylhydrazines and heterocyclic hydrazines as nitrogen-containing nucleophiles (2) into the corresponding 1-amino-5,6,7,8-tetrahydroquinoline-2,5-diones (5-17) was investigated. The reaction was carried out in the mixture of ethanol, water and triethylamine, and the corresponding quinoline-2,5-diones were obtained in 52-89% yields. The compounds (3) and (4) were proposed to be intermediates in this transformation.
TL;DR: Methylphytylbenzoquinone was synthesized from δ-tocopherol by a simple two-step sequence as discussed by the authors, and the biological activity of the product corresponds to the natural biosynthetic precursor of vitamin E. The above method is a general procedure applicable to the preparation of any of the tocopherol derivatives.
TL;DR: In this paper, the electron impact ionization mass spectra of compounds 4,5 and 6a,b show a weak molecular ion peak and a base peak of m/z 89,m/z 280.
Abstract: 3-Hydroxybenzopyran[3,2-c]-[1]-benzopyran-6,7-diones (3) and 3-methoxycarbonylcoumarin (4) were prepared via condensation of 1 with resorcinol in the presence of sodium methoxide. The chemical behavior of 3 towards acetic anhydride, alkyl halides and diazonium chloride is described. The electron impact ionization mass spectra of compounds 4,5 and 6a,b show a weak molecular ion peak and a base peak of m/z 89, m/z 280. m/z 91 and m/z 120 resulting from a cleavage fragmentation respectively. The molecular ion of compounds 3, 6b, and 7a is a base peak of m/z 280, m/z 366 and m/z 488 respectively. Compound 7a give a characteristic fragmentation pattern with a two very stable fragmentation of m/z 383 and m/z 77.
TL;DR: The pyridinium methylid (5), generated from 1-(4-oxo-4H-1-benzopyran-2-yl)methylpyrinium iodide (4) in the presence of a base, undergoes cycloaddition with dimethyl acetylenedicarboxylate and ethyl propiolate, thecycloadducts rapidly aromatising to the indolizines (8) and (9) respectively as discussed by the authors.
Abstract: The pyridinium methylid (5), generated from 1-(4-oxo-4H-1-benzopyran-2-yl)methylpyridinium iodide (4) in the presence of a base, undergoes [3+2] cycloaddition with dimethyl acetylenedicarboxylate and ethyl propiolate, thecycloadducts rapidly aromatising to the indolizines (8) and (9), respectively. Similar cycloaddition of 5 with ethyl acrylate and acrylonitrile is also followed by dehydrogenation giving respectively the indolizines (9) and (10).
TL;DR: In this article, the synthesis of the novel 2,4,6-triaryl-1-(spiro[2H-1-benzopyran-2,2′-indoline]-6-yl)pyridinium perchlorates was reported.
TL;DR: In this paper, a regioselective method was developed for synthesis of substituted spiro(s) having one or two hydroxyl groups on the benzene ring.
Abstract: We have developed a novel regioselective method for synthesis of substituted spiro([1]benzopyran-2,4'-(1'H)pyrimidine)-2'-(3'H)thiones and spiro([1]benzopyran-2,4'-(1'H)pyrimidin)-2'-(3'H)ones having one or two hydroxyl groups on the benzene ring.
TL;DR: The title compound 3,3'-[o-phenylenebis(methyleneoxy)]bis(6-chloroflavone), C(38)H(24)Cl(2)O(6), (I), crystallizes in the monoclinic space group C2/c, with the molecules lying across twofold rotation axes so that there is half a molecule in the asymmetric unit.
Abstract: The title compound 3,3'-[o-phenylenebis(methyleneoxy)]bis(6-chloroflavone), C(38)H(24)Cl(2)O(6), (I), crystallizes in the monoclinic space group C2/c, with the molecules lying across twofold rotation axes so that there is half a molecule in the asymmetric unit, while the other title compound, 3,3'-propylenedioxybis[6-chloro-2-(2-furyl)-4H-1-benzopyran-4-one], C(29)H(18)Cl(2)O(8), (II), crystallizes in monoclinic space group P2(1)/n with one molecule in the asymmetric unit. In both compounds, the benzopyran moiety is nearly planar, with dihedral angles between the two fused rings of 1.43 (8) degrees in (I), and 2.54 (7) and 3.00 (6) degrees with respect to the benzopyran moieties in the two halves of (II). The furan rings are twisted by 8.3 (1) and 8.4 (1) degrees in the two halves of (II). In both compounds, the molecular structure is stabilized by intramolecular C-H.O hydrogen bonds, while the crystal packing is stabilized by C-H.Cl and C-H.O intermolecular hydrogen bonds in (I) and (II), respectively.
Patent•
24 Dec 2003
TL;DR: A process for preparing 3-(formamide)-7-(methylsulfonylamine)-6-(phenoxy) -4H-1-(benzopyran)-4-one as an anti-inflammatory from 3-phenoxy-4-methyl sulfonylamines-6- methoxyacetophenone includes demethylation, cyclization, catalytic hydrogenation, bromination, vinylog and amination as discussed by the authors.
Abstract: A process for preparing 3-(formamide)-7-(methylsulfonylamine)-6-(phenoxy) -4H-1-(benzopyran)-4-one as an anti-inflammatory from 3-phenoxy-4-methylsulfonylamine-6- methoxyacetophenone includes demethylation, cyclization, catalytic hydrogenation, bromination, vinylog and amination