Showing papers on "Benzopyran published in 1998"
Patent•
18 Apr 1998TL;DR: A class of benzopyran derivatives for use in treating cyclooxygenase-2 mediated disorders was described in this article, where compounds of particular interest are defined by Formula (I'), wherein X, A?1, A2, A3, A4?, R, R', R?1 and R2? are as described in the specification.
Abstract: A class of benzopyran derivatives is described for use in treating cyclooxygenase-2 mediated disorders. Compounds of particular interest are defined by Formula (I'), wherein X, A?1, A2, A3, A4?, R, R', R?1 and R2? are as described in the specification.
148 citations
TL;DR: The structure of clusifoliol isolated from whole plants of Peperomia clusiifolia has been established as 3,4-dihydro-2,7-dimethyl-6-(3-methyl-2-butenyl)-2-(4methyl-1,3-pentadienyl)2H-1-benzopyran-5-ol by spectroscopic methods.
38 citations
TL;DR: In this paper, 4-heterocyclic substituted coumarin derivatives are screened for antiinflammatory activity in vitro through their antiproteolytic activity, the interaction with 1,1-diphenyl-2-picrylhydrazyl and the ability to affect superoxide anion and to inhibit β-glucuronidase and soybean lipoxygenase.
34 citations
TL;DR: C-(4-oxo-4 H [1]benzopyran-3-yl)- N -phenylnitrones ( 1a-c ) undergo facile rearrangements on refluxing in benzene, yielding 2-( N -naphlamino)-4oxo4H [1]-benzophrin-3 carboxaldehydes ( 2a-C, 70%) and 3-(phenyliminomethylene)-chroman-2,4-diones ( 3a- c, 25%) in
30 citations
TL;DR: In this article, the thermolyses of dimethyl 1-diazo-2-oxo(2-(N,N-disubstituted aminomethyl)phenyl)-ethylphosphonates6a-e or the related ester 6f afford 1H-2benzopyran derivatives 9a-f through a 3-step sequence involving Wolff rearrangement, [1,5] hydride shift and subsequent ring closure.
20 citations
TL;DR: In this paper, the synthesis of 8 hydroxy-and 2-oxopyranochromone-3-carboxaldehydes 3, 5 and their reactions with 2-hydroxyaniline, 2,4-dinitrophenylhydrazine and 2-benzothiazolyl hydrazine were investigated.
Abstract: The synthesis of eight hydroxy- and 2-oxopyranochromone-3-carboxaldehydes 3, 5 and their reactions with 2-hydroxyaniline, 2,4-dinitrophenylhydrazine and 2-benzothiazolylhydrazine were investigated. Products were confirmed by IR, NMR spectral and elemental analysis data. The semi-empirical AM1 quantum-chemical method has been used to study optimal geometries and heats of formation of synthesized 3-formylchromones.
18 citations
16 citations
TL;DR: Results would demonstrate that 5-oxo-3,4-diazabicyclo[4.1.0]hept- 2-en-2-yl)oxy moieties are effective as the substituents at the 4-position of benzopyran-type potassium channel openers.
Abstract: A series of 3,4-dihydro-3-hydroxy-4-[(5-oxo-3,4-diazabicyclo[4.1.0]hept- 2-en-2-yl)oxy]-2H-1-benzopyrans and their analogues were synthesized and evaluated on potassium channel opening and hypotensive activities. Compound (-)-13B with a (4-methyl-5-oxo-3,4-diazabicyclo[4.1.0]hept-2-en-2-yl)oxy group for the 4-position of the benzopyran ring was 3 times as potent as EMD 57283 (II), the lead compound, in hypotensive activity. The results would demonstrate that 5-oxo-3,4-diazabicyclo[4.1.0]hept-2-en-2-yloxy moieties are effective as the substituents at the 4-position of benzopyran-type potassium channel openers.
15 citations
TL;DR: The leaves of Melicopte ptelefolia afforded two new 2,2-dimethyl-2H-1-benzopyran dimers named 5,5' -dimethoxy-alloagerasanin and melifolin this article.
14 citations
TL;DR: The reaction of the title aldehyde 1 with acetylacetone 2 gives benzophenone 8 along with the Knoevenagel-type product 5 under acidic conditions as discussed by the authors.
Abstract: Reaction of the title aldehyde 1 with acetylacetone 2 gives benzophenone 8 along with the Knoevenagel-type product 5 under acidic conditions.
14 citations
TL;DR: When 2-imino-2H-benzopyran-3-carboxamide 1 (X = H) is dissolved in [2H6]dimethyl sulfoxide, NMR spectra show that a mixture of 1 and the isomeric 2-cyano-3-(2-hydroxyphenyl)prop-2-ene-1-Carboxamide 3 (X ǫ=H) is present.
Abstract: When 2-imino-2H-benzopyran-3-carboxamide 1 (X = H) is dissolved in [2H6]dimethyl sulfoxide, NMR spectra show that a mixture of 1 and the isomeric 2-cyano-3-(2-hydroxyphenyl)prop-2-ene-1-carboxamide 3 (X = H) is present. Other benzopyran-2-imines behave similarly; the degree of isomerisation varies considerably, depending on the nature and position of the substituents present.
TL;DR: A series of optically active tetrahydro-oxazino[2,3-c]benzopyran derivatives have been synthesized and evaluated for potassium channel opening activity and 9-carb onitrile was identified as a bladder-selective potassium channel opener.
TL;DR: The methanol extract of Brazilian propolis was fractionated by HPLC, based on human hepatocellular carcinoma (HuH 13) cell cytotoxicity assay, and a new benzo-y-pyran derivative (PM-3) with a molecular formula of C19H22O3 was isolated.
Abstract: The methanol extract of Brazilian propolis was fractionated by HPLC, based on human hepatocellular carcinoma (HuH 13) cell cytotoxicity assay. A new benzo-γ-pyran derivative (PM-3) with a molecular formula of C19H22O3 (MW: 298.38) was isolated. The structure of this colorless compound was determined as 3-[2-dimethyl-8-(3-methyl-2-butenyl) benzopyran]-6-propenoic acid. This compound was chemically synthesized by cyclisation of artepillin C (3-[4-hydroxy-3,5-bis (3-methyl-2-butenyl) phenyl]-2-propenoic acid).
TL;DR: Enantiomer (-)-2 was obtained from a (+)-conduritol F derivative that was more active than (+)-2 in the Wessler's model.
Journal Article•
TL;DR: In this article, a new rearrangement of 2-imino-2H-1-benzopyran-3-carboxamides (1) under action of anthranilic acid (2) as A/-nucleophile has been revealed.
Abstract: New rearrangements of 2-imino-2H-1-benzopyran-3-carboxamides (1) under action of anthranilic acid (2) as A/-nucleophile have been revealed. Starting from readily available 2-imino-2H-1-benzopyran-3-carboxamides (1) and anthranilic acid (2) and depending on reaction conditions, 2-(2-oxo-2H-1-benzopyran-2-yl)-3H-quinazolin-4-ones 3a.b and 2-oxo-2H-1 -benzopyran-3-(A/-2-carboxyphenyl)carboxamides 4a.b have been prepared via the rearrangements. Possible mechanisms of these rearrangements have been discussed. Compounds comprising coumarin backbone (1-4) are of interest both for the range of pharmacological properties and for their chemistry. In view of the ubiquity of coumarin moiety in a variety of biologically active compounds, the synthesis of various analogs is important in gauging their potential as a source of chemotherapeutics. From the above line of reasoning we directed our research towards the development of a new procedures for synthesis of various coumarin derivatives (5-8) of biological interest. As part of our continuing studies (5) on reactivity of 3-substituted 2-imino-2H-1-benzopyrans under action of Nnucleophiles, we wish to report on "unusual" reactions of 2-imino-2H-1-benzopyran-3-carboxamides ( I ) with anthranilic acid (2) as a simple and efficient way to obtain different 2-oxo-2H-1-benzopyran derivatives via novel rearrangements (9). As shown in Scheme 1, either compounds 3 or 4 were formed (10) depending on reaction conditions. Refluxing of compounds 1a.b (5,11) and 2 in degassed toluene afforded compounds 3a.b (12) in moderate yields as only products. It is pertinent to note that strong liberation of ammonia was detected. A possible mechanism of coumarin and 4(3H)quinazolinone moieties formation via a rearrangement of 2-imino-2H-1-benzopyran-3-carboxamides (1) under action of anthranilic acid (2) as A/-nucleophile is shown in Scheme 2.
TL;DR: Several acetoacetanilides were trilithiated in excess lithium diisopropylamide, and the resulting polylithiated intermediates were regioselectively condensed with lithiated methyl salicylates followed by acid cyclization to substituted 4-oxo-N-aryl-4H-1-benzopyran-2-acetamides as mentioned in this paper.
TL;DR: In this paper, a general method for ring closure of 1-substituted 2-(-hydroxymethyl)-phenylethanols to 3-substantituted isochromanes using p-TsOH supported on silica gel is reported.
TL;DR: In this article, the synthesis of substituted (CN and SR) 2-methylene-benzopyran and 2 -methylchromones is described, and the synthesis process is described in detail.
Patent•
03 Nov 1998
Abstract: Sulfonamide-substituted benzopyran derivatives, processes for their preparation, their use as a medicament, and pharmaceutical preparations comprising them Compounds of the formula I ##STR1## having the meanings of the substituents indicated in the claims are outstandingly active substances for the production of medicaments for the prophylaxis and for the therapy of cardiovascular disorders, in particular arrhythmias, for the treatment of ulcers of the gastrointestinal region or for the treatment of diarrheal diseases
TL;DR: The title benzopyranones 1−3 gave the benzo[b]furan 7 and the benzos[b]-cyclopropa[e]pyrans 8 and 9 with chloroacetone in acetone containing anhydrous potassium carbonate and a catalytic amount of potassium iodide, respectively, but gave the 1-benzopyrans 10, 11 and 14 in dichloromethane in the presence of Brockman neutral alumina, respectively.
Abstract: The title benzopyranones 1–3 give the benzo[b]furan 7 and the benzo[b]cyclopropa[e]pyrans 8 and 9 with chloroacetone in acetone containing anhydrous potassium carbonate and a catalytic amount of potassium iodide but give the 1-benzopyranones 10, 11 and 14 in dichloromethane in the presence of Brockman neutral alumina, respectively.
Patent•
16 Jun 1998
TL;DR: In this article, the subject compound is represented by formula I (R1 is a straight or branched chain 1-9C alkyl; R2, R4 and R5 are independently H, a straight-branched-chain 1-nine-c-alkyl or acyl; X is carbonyl, methylene; Y is a single-bond or the like; R6 is a simple-single-link or single-link.
Abstract: PROBLEM TO BE SOLVED: To obtain the subject novel compound that can be used not only in the treatment of diabetes but also in treatment of side-effects of diabetic diseases. SOLUTION: This compound is represented by formula I (R1 is a straight or branched chain 1-9C alkyl; R2 , R4 and R5 are independently H, a straight or branched chain 1-9C alkyl; R3 is H, a straight or branched chain 1-9 alkyl or acyl; X is carbonyl, methylene; Y is H, a straight or branched chain 1-9C alkyl; A is a single bond or the like; R6 is a straight or branched chain alkyl in case that A is a single bond) or its stereoisomers or pharmaceutically acceptable acid or base adducts, typically 4 chloro N-(6-acetoxy-(3,4-dihydro 2,5,7,8 tetramethy-2H-1-benzopyran-2-carbonyl)benzenesulfonamide. The compound of formula I is prepared, for example, by condensation reaction of a compound of formula II (Z is hydroxyl) with a compound of formula III.
Patent•
14 Apr 1998TL;DR: A process for the manufacture of the racemic compound of the formula (I), its R-enantiomer (formula R-(I)) and its S-enantomer (S-(I)), and pharmaceutically acceptable salts and/or solvates thereof, as well as new intermediates obtained and used in the process is described in this article.
Abstract: A process for the manufacture of the racemic compound of the formula (I), its R-enantiomer (formula R-(I)) and its S-enantiomer (formula S-(I)), and pharmaceutically acceptable salts and/or solvates thereof, as well as new intermediates obtained and used in the process.
TL;DR: In this article, the thermal sigmatropic rearrangement of 6-cyclohex-2-enyloxycoumarin (3) in refluxing N, N-diethylaniline.
TL;DR: In this paper, 4-heterocyclic substituted coumarin derivatives are screened for antiinflammatory activity in vitro through their antiproteolytic activity, the interaction with 1,1-diphenyl-2-picrylhydrazyl and the ability to affect superoxide anion and to inhibit β-glucuronidase and soybean lipoxygenase.
Abstract: 1,3-Cycloaddition reactions of new 2-oxo-2H-[1]benzopyran-4-carbonitrile N-oxide 2 with dipolarophiles, o-aminophenols and o-phenylenediamine resulted in 4-heterocyclic substituted coumarin derivatives. These derivatives are screened for antiinflammatory activity in vitro through their antiproteolytic activity, the interaction with 1,1-diphenyl-2-picrylhydrazyl and the ability to affect superoxide anion and to inhibit β-glucuronidase and soybean lipoxygenase.
Patent•
28 Sep 1998
TL;DR: In this article, a medicine consisting of a benzopyran derivative of the formula and its salt as active ingredients was obtained by obtaining a methanol extract from propolis ground by a mixer, separating the methanoil extract by absorption-based column chromatography using a silica gel column, subjecting the liquid to inclination elution by concentration gradient using methyl chloride and methanols, collecting a fraction having 100-95% methyl chloride concentration, and elution fractions (Rf value: 0.5% v/v) as the developing solvents, diss
Abstract: PROBLEM TO BE SOLVED: To obtain a medicine useful as an antitumor agent by including a specific benzopyran derivative and its salt as active ingredients. SOLUTION: This medicine comprises a benzopyran derivative of the formula and its salt as active ingredients. The compound of the formula is obtained by obtaining a methanol extract from propolis ground by a mixer, separating the methanol extract by absorption-based column chromatography using a silica gel column, subjecting the liquid to inclination elution by concentration gradient using methyl chloride and methanol, collecting a fraction having 100-95% methyl chloride concentration, and elution fractions (Rf value: 0.3) of methyl chloride and methanol (in a ratio of 95%:5% v/v) as the developing solvents, dissolving the concentrate in a mixed solution of methanol, or the like, separating the solution by liquid chromatography using an ODS-based column, eluting the fractions with a mixed solution of acetonitrile, irradiating the main fraction with ultraviolet rays, distilling the solvent of the resultant photoisomer fractions away, and further separating the fractions by liquid chromatography using an ODS-based column to carry out elution, or the like.