Showing papers on "Benzopyran published in 1991"
••
TL;DR: In conformation/activity investigations it was found that the activity of the 4-substituted benzopyran derivatives seems to be dependent on the relative orientation of their ring systems.
Abstract: By aldol condensation of 4-chromanones with paraformaldehyde, 3-alkylenechromanones 10 were obtained which gave 3-alkylchromenes following reduction and dehydration. Subsequent 3-chloroperbenzoic acid oxidation produced the versatile epoxide intermediates 15, from which 3,4-epoxy-3,4-dihydro-2,2,3-trimethyl-2H-1-benzopyran-6-carbonitrile (15a) was resolved into its enantiomers by entrainment. In addition to the methyl group, the benzyl, alkyloxymethyl, and 2-nitroethyl residues could be introduced in the 3-position. Treatment of 15a with 2-pyridone simultaneously gave N- and O-substituted products 19a and 20. 19a easily gave 4-(1,2-dihydro-2-oxo-1-pyridyl)chromene 21 by treatment with base. The corresponding pyrrolidinone compounds 26 and 27 were obtained by a slightly modified procedure. Reaction with 2,4-dihydroxypyridine or 3,6-pyridazinediol resulted in the exclusive formation of 4-(heterocyclyloxy)chromanols (31 and 32). Treatment of 15a with 3-amino-6-pyridazinol gave 4-(3-amino-1,6-dihydro-6-oxo-1-pyridazinyl)chromanol derivative 34 lacking an NH bridge. This could be established after methylation of the ring-nitrogen atom (----35). Trans-configurated 3-methyl-4-pyridone compound 36 was obtained by addition of methyllithium to chromene 3. Hyperpolarizing and antispasmodic or relaxing effects of the compounds were determined in organ bath studies using pig coronary arteries precontracted with acetylcholine or rabbit main pulmonary arteries precontracted with noradrenaline. In the 3-methyl series the classical pyridone and pyrrolidinone structures (9, 21, 26, 27) were only weakly active or inactive, but the corresponding 4-(heterocyclyloxy) and 4-(heterocyclylamino) derivatives (31, 32, 35) were even more potent than the demethyl analogues. In conformation/activity investigations it was found that the activity of the 4-substituted benzopyran derivatives seems to be dependent on the relative orientation of their ring systems.
58 citations
•
19 Jul 1991TL;DR: In this article, a series of novel photochromic benzopyran and naphthopyrin compounds substituted with (1) a cyclopropyl group and (2) a phenyl, substituted phenyl or 5-member aromatic heterocyclic group at the 2-position of the benzophyran ring were described.
Abstract: Described are a series of novel photochromic benzopyran and naphthopyran compounds substituted with (1) a cyclopropyl group and (2) a phenyl, substituted phenyl, or 5-member aromatic heterocyclic group at the 2-position of the benzopyran or naphthopyran ring. Also described are organic host materials that contain or that are coated with such compounds. Articles such as ophthalmic or plano lenses that incorporate the novel pyran compounds or combinations of the novel pyran compounds with other complementary photochromic compounds are described.
50 citations
•
18 Jun 1991TL;DR: In this article, the authors describe compounds of formula (I) which are useful in association with a pharmaceutical carrier as antiatherosclerotic agents. But they do not specify the type of carrier.
Abstract: This invention relates to compounds of formula (I) which are useful in association with a pharmaceutical carrier as antiatherosclerotic agents. In addition, various compounds of formula (I) are useful inhibitors of cell proliferation.
47 citations
••
TL;DR: 6-cyano-2,2-dimethyl-N-methyl-N -methyl-2H-1-benzopyran-4-thiocarboxamide was shown to be a potent potassium channel activator in vitro and to provide prolonged protection to guinea pigs from the respiratory effects of inhaled histamine.
Abstract: Structural modifications of the potassium channel activator cromakalim (1) are described in which the amide moiety at C-4 has been replaced by carboxamide and thiocarboxamide functions. Analogues in which the hydroxyl group at C-3 has been oxidized or removed are also disclosed. Such analogues display an interesting profile of smooth muscle relaxant activity in the guinea pig isolated trachea, not all of which appears to result from the opening of potassium channels, but few compounds retain useful in vivo activity. However, one compound in particular, 6-cyano-2,2-dimethyl-N-methyl-2H-1-benzopyran-4-thiocarboxamide (13) was shown to be a potent potassium channel activator in vitro and to provide prolonged protection to guinea pigs from the respiratory effects of inhaled histamine.
36 citations
•
22 Feb 1991TL;DR: Piperidine derivatives of formula (SEE FORMULA) wherein A is a radical of formula -CH 2-CH2- (a-1) to (a)-3) may be replaced by a C 1-6alkyl radical as mentioned in this paper.
Abstract: Piperidine derivatives of formula (SEE FORMULA) wherein A is a radical of formula -CH2-CH2- (a-1), -CH2-CH2-CH2- (a-2), or -CH2-CH2-CH2-CH2- (a-3), wherein one or two hydrogen atoms in said radicals (a-1) to (a-3) may be replaced by a C1-6alkyl radical; R1 is hydrogen or halo; R2 is hydrogen, amino, mono or di(C1-6alkyl)amino or C1-6alkylcarbonylamino; R3 is hydrogen or C1-6alkyl; L is C3-6cycloalkyl, C5-6cycloalkanone, C3-6alkenyl optionally substituted with aryl, or L is a radical of formula -Alk-R4 (b-1), -Alk-X-R5 (b-2), -Alk-Y-C(=O)-R7 (b-3), or -Alk-Y-C(=O)NR9R10 (b-4), the N-oxide foams, addition salts and stereochemically isomeric form thereof, said compounds having gastrointestinal motility stimulating properties pharmaceutical compositions containing these compounds as active ingredient, and a method of preparing said compounds and pharmaceutical compositions.
29 citations
•
14 Jun 1991TL;DR: In this paper, a new method for the treatment of arrhythmia and ischemia conditions using compounds of the formula "STR1##" was proposed, where A can be either oxygen or sulfur.
Abstract: A new method for the treatment of ischemia conditions and arrhythmia is disclosed. The method uses compounds of the formula ##STR1## wherein A can be --CH 2 --, --O--, --NR 9 --, --S--, --SO--, --SO 2 --; X can be oxygen or sulfur; Y can be --NR 8 , --O--, --S--, --CH 2 -- and the R groups are as defined herein. Novel compounds within the definition of formula I are also disclosed.
25 citations
••
TL;DR: The compounds described in this paper illustrate the importance of the benzopyran oxygen and C(4) substituent on antihypertensive activity in the cromakalim series of potassium channel activators.
Abstract: The synthesis and oral antihypertensive activity in conscious spontaneously hypertensive rats of two new series of compounds related to the prototype potassium channel activator cromakalim (1) are described. In the first series, replacement of the benzopyran oxygen atom by nitrogen or methylene led to the 1,2,3,4-tetrahydroquinoline 12 and 1,2,3,4-tetrahydronaphthalene 13, which were both less active than 1. However, in contrast to the equivalent activity found previously for 1 and its dehydrated analogue 28, the dihydronaphthalene 27 was found to be more active than 13. In the second series, replacement of the C(4) amide nitrogen atom in acyclic amides related to cromakalim by methylene gave ketone 16 that was less active than the corresponding amide 15. However, replacement of the 4-acetonyl substituent in 16 by N,N-dimethylacetamido as in compound 22 resulted in a marked enhancement in activity. The compounds described in this paper thus illustrate the importance of the benzopyran oxygen and C(4) substituent on antihypertensive activity in the cromakalim series of potassium channel activators.
24 citations
••
TL;DR: Substituted 5,6,7,8-tetrahydrO-4H-1-benzopyran and 4H-pyran derivatives were synthesized from their corresponding substituted 1,5 diketones with vilsmeier haack reagent in moderate yields.
22 citations
••
TL;DR: In this paper, the resonance Raman spectra of 2,2′-spirobi[2H-1-benzopyran] in various solvents reveal that at least two isomers exist in solution, the relative abundance of which depends on polarity and hydrogen-bond donor ability of the solvent.
21 citations
••
TL;DR: With few mesogenic chromone derivatives in the literature, the synthesis of 7-[4′-n-alkyloxybenzoyloxy] isoflavones was carried out in this paper.
Abstract: With few mesogenic chromone derivatives in the literature the synthesis of 7-[4′-n-alkyloxybenzoyloxy) isoflavones was carried out. The resulting homologous series was characterized by elemental an...
18 citations
••
•
26 Jul 1991
TL;DR: A benzopyran derivative represented by general formula (I) has a K+ channel activating effect and so is widely applicable for treating, for example, asthma and epilepsy, wherein X represents O, =S, =N-Z (wherein Z represents lower alkyl, etc.).
Abstract: A benzopyran derivative represented by general formula (I), which has a K+ channel activating effect and so is widely applicable for treating, for example, asthma and epilepsy, wherein X represents =O, =S, =N-Z (wherein Z represents lower alkyl, etc.), or =CHNO?2?; Y represents substituted amino, alkoxy, alkylthio, etc.; and R1 to R7 represent each hydrogen, lower alkyl, etc.
••
TL;DR: In this paper, allyl phenols react with m-chloroperoxybenzoic acid (m-CPBA) in dry chloroform to give chroman-3-ols in a single step.
••
TL;DR: In this paper, a two-step synthesis of 6-alkyl-4-hydroxymethyl-3-chromene from addition of phenyl vinyl sulfoxide carbanion to 5'-alkyl 2'-hydroxyacetophenone is described.
Abstract: A two-step synthesis of 6-alkyl-4-hydroxymethyl-3-chromene (6-alkyl-4-hydroxymethyl-2H-1 -benzopyran) from addition of phenyl vinyl sulfoxide carbanion to 5'-alkyl-2'-hydroxyacetophenone is described. Application to the synthesis of 4-methyl-3-chromene (4-methyl-2H-1-benzopyran) and 4,4-dimethylchroman (3,4-dihydro-4,4-dimethyl-2H-1-benzopyran) is also presented
••
TL;DR: In this article, the structure of the new benzodipyrans (4) were confirmed on the basis of elemental analysis and spectral studies, and the pyrazole derivatives (5) were obtained when compounds were allowed to react with hydrazine hydrate, and their corresponding 5methoxy-8-methyl-2,6-dioxo 2H, 6H-benzo[1,2-b:5,4-b′]dipyran and its thio analogue were obtained respectively.
Abstract: When 6-formyl-7-hydroxy-5-methoxy-2-methylbenzopyran-4-one (1a), was reacted with ketenylidene(2a) and thioketenylidenetriphenylphosphorane (2b), the corresponding 5-methoxy-8-methyl-2,6-dioxo 2H, 6H-benzo[1,2-b:5,4-b′]dipyran (4a) and its thio analogue (4b), were obtained respectively. The structure of the new benzodipyrans (4) were confirmed on the basis of elemental analysis and spectral studies. Moreover, the pyrazole derivatives (5), were obtained when compounds (4) were allowed to react with hydrazine hydrate.
••
TL;DR: In contrast to the corresponding compounds lacking alkoxy substituents, the 2-benzopyran-3-ones 5, 6, 7 and 9 are stable and easily isolated as discussed by the authors.
Abstract: In contrast to the corresponding compounds lacking alkoxy substituents, the 2-benzopyran-3-ones 5, 6, 7 and 9 are stable and easily isolated. In contrast to the 6-methoxy derivative 7, the 7-methoxy isomer 8 cannot be isolated; the stabilising effect of the 6,7-methylenedioxy group in 5 and 9 is therefore due to the alkoxy group at C-6. This is consistent with a donor-acceptor interaction involving the C-6 alkoxy group and the pyrone carbonyl which decreases reactivity towards nucleophilic attack by water.
••
TL;DR: The duration of the blood pressure lowering effect was found to be related to the lipophilicity of the agent and was independent of the potency.
•
•
09 Apr 1991
TL;DR: In this article, the authors defined the compounds of the formula where each R independently represents hydrogen, lower alkyl, halogen, trifluoromethyl, lower alkoxy, carbocyclic or heter-cyclic aryl-lower alkyls, or C3-C7-cycloalkyl-lower-alkyl.
Abstract: The invention relates to the compounds of the formula wherein each R independently represents hydrogen, lower alkyl, halogen, trifluoromethyl, lower alkoxy, carbocyclic or heterocyclic aryl, carbocyclic or heterocyclic aryloxy, carbocyclic or heterocyclic aryl-lower alkyloxy, carbocyclic or heterocyclic aryl-lower alkyl, C3-C7-cycloalkyl-lower alkyloxy, or C3-C7-cycloalkyloxy; R1 represents hydrogen, lower alkyl or carbocyclic aryl; R2 represents hydrogen or lower alkyl; Y represents oxygen (O), sulfur (S), sulfinyl or sulfonyl; n represents 1, 2 or 3; A represents a direct bond or lower alkylene; Z represents wherein R3 represents hydrogen or acyl; R4 represents lower alkyl, C3-C7-cycloalkyl, carbocyclic or heterocyclic aryl, carbocyclic or heterocyclic aryl-lower alkyl, or C3-C7-cycloalkyl-lower alkyl; or Z represents wherein X represents oxygen or sulfur, R3 represents hydrogen or acyl; R5 represents lower alkyl, lower alkoxycarbonyl-lower alkyl, C3-C7-cycloalkyl, carbocyclic or heterocyclic aryl, carbocyclic or heterocyclic aryl-lower alkyl, C3-C7-cycloalkyl-lower alkyl, amino, mono- or di-lower alkylamino, lower alkenylamino, lower alkynylamino, carbocyclic or heterocyclic aryl-lower alkylamino, carbocyclic or heterocyclic arylamino, C3-C7-cycloalkylamino, C3-C7-cycloalkyl-lower alkylamino, lower alkoxycarbonyl-lower alkylamino, or lower alkoxy; R6 and R7 independently represent hydrogen or lower alkyl; and pharmaceutically acceptable salts thereof; which are useful as 5-lipoxygenase inhibitors.
••
TL;DR: A new heterocycle, furo[4,3,2-de][1]benzopyran (2), was synthesized in this paper, which has both properties of benzofuran and 4-methylenepyran.
•
17 Dec 1991
TL;DR: A method of inhibiting microorganisms, including bacteria, using benzopyran phenol derivates from propolis was proposed in this paper, where propolis is extracted with an alcohol, and the resulting compounds are effective as antibacterial, antiviral or immunostimulating agents.
Abstract: A method of inhibiting microorganisms, including bacteria, using benzopyran phenol derivates from propolis. Propolis is extracted with an alcohol, and the resulting compounds are effective as antibacterial, antiviral or immunostimulating agents.
••
TL;DR: The benzopyran heterocycle is planar within experimental errors (max. deviation from the best mean plane through the ten atoms 0.031 angstrom) for 1848 observed reflections.
Abstract: C17H14O4, M(r) = 282.30, monoclinic, P2(1)/c, a = 12.498 (4), b = 9.490 (2), c = 12.184 (2) angstrom, beta = 107.87 (2)degrees, V = 1375.4 (6) angstrom 3, Z = 4, D(x) = 1.36 g cm-3, Cu K-alpha, lambda = 1.54178 angstrom, mu = 7.98 cm-1, F(000) = 592, T = 291 K, R = 0.042 for 1848 observed reflections. The benzopyran heterocycle is planar within experimental errors (max. deviation from the best mean plane through the ten atoms 0.031 angstrom). The dihedral angle between the heterocycle and the phenyl ring is 23.5 (5)degrees. The methoxy groups are nearly coplanar with their aromatic rings (torsion angles about C(arom)-O are 4-6-degrees).
•
25 Jul 1991TL;DR: A benzopyran derivative represented by general formula (I), a pharmaceutically acceptable salt thereof, and an ACAT inhibitor, an antihyperlipemic agent and an antiarteriosclerotic composition each containing the same as the active ingredient.
Abstract: A benzopyran derivative represented by general formula (I), a pharmaceutically acceptable salt thereof, and an ACAT inhibitor, an antihyperlipemic agent and an antiarteriosclerotic composition each containing the same as the active ingredient; formula (I) wherein one of X and Y represents the group (1) and the other of X and Y and R?1 to R10? represent each a substituent.
••
TL;DR: In this paper, it has been shown that 1,3-dicyclohexyl carbodiimide (DCC) with 2-hydroxypyridine, disuccinimidyl carbonate (DSC), 2-ethoxy-N-thoxycarbonyl-1,2-dihydroquinoline (EEDQ) of 2-isobutoxy-nisobuteoxy-carbonyln-1-isopyranone (IIDQ) are much more efficient reagents.
Abstract: The generation of methoxy-substituted 3H-2-benzopyran-3-ones from o-acylphenylacetic acid derivatives in acetic anhydride at 140 °C and their in situ Diets–Alder reactions being inefficient in the synthesis of some carbocyclic compounds, alternative reagents have been used. It is shown that, e.g. 1,3-dicyclohexylcarbodiimide (DCC) with 2-hydroxypyridine, disuccinimidyl carbonate (DSC), 2-ethoxy-N-ethoxycarbonyl-1,2-dihydroquinoline (EEDQ) of 2-isobutoxy-N-isobutoxycarbonyl-1,2-dihydroquinoline (IIDQ) are much more efficient reagents.Using these alternative reagents the formation of side-products from the benzopyranone, e.g. chrysene, can be avoided; with the modified DCC-method the 6,7-dimethoxy-1 -methyl-2-benzopyran3-one intermediate 8a can be identified spectroscopically. An exemplified procedure with IIDQ is proposed, opening new prespectives for Diets–Alder reactions of unstable or less reactive dienophiles with problematic benzopyranones.
••
•
04 Feb 1991TL;DR: Piperidine derivatives of formula as mentioned in this paper have gastrointestinal motility stimulating properties, such as N-oxide forms, addition salts and stereochemically isomeric forms thereof, and a method of preparing said compounds and pharmaceutical compositions.
Abstract: Piperidine derivatives of formula ##STR1## wherein A is a radical of formula ##STR2## wherein one or two hydrogen atoms in said radicals (a-1) to (a-3) may be replaced by a C 1-6 alkyl radical; R 1 is hydrogen or halo; R 2 is hydrogen, amino, mono or di(C 1-6 alkyl)amino or C 1-6 alkylcarbonylamino; R 3 is hydrogen or C 1-6 alkyl; L is C 3-6 cycloalkyl, C 5-6 cycloalkanone, C 3-6 alkenyl optionally substituted with aryl, or L is a radical of formula ##STR3## the N-oxide forms, addition salts and stereochemically isomeric forms thereof, said compounds having gastrointestinal motility stimulating properties. Pharmaceutical compositions containing these compounds as active ingredient, and a method of preparing said compounds and pharmaceutical compositions.
••
•
25 Sep 1991TL;DR: In this article, a novel heterocyclic compound with acyl-CoA:cholesterol acyltransferase inhibitory activity was described, and a method for preparing it and its use was described.
Abstract: Novel heterocyclic compound of the general formula: ##STR1## wherein ring A and ring B each means a benzene ring which is substituted or unsubstituted; X means a group of the formula: ##STR2## wherein R2 is hydrogen, an alkyl or an alkoxy; m is 0 or 1, the formula: ##STR3## wherein R3 is hydrogen or an alkyl, or the formula: --O--CO--; Y means a bond, --NH--, an C1 or 2 alkylene group or --CH═CH--; R1 means a hydrocarbon group which is substituted or unsubstituted; and n means a whole number of 3 through 6, or a salt thereof, having excellent acyl-CoA:cholesterol acyltransferase inhibitory activity, and a method for preparing it and its use.
•
31 Jan 1991
TL;DR: New benzopyran derivatives of formula: (1) in which R 1 is hydrogen, halogen, hydroxy, alkoxy, nitro, amino, alkylsulphonamido, bis(alkylsulphonyl) amino or acylamino, X is nitrogen or a >CH-radical R 2 and R 3 are identical and are hydrogen or alkyl, their isomeric forms and mixtures thereof, and their acid addition salts, can be used as antiarrhythmic and antifibrillation agents as discussed by the authors.
Abstract: New benzopyran derivatives of formula: (I) in which R1 is hydrogen, halogen, hydroxy, alkoxy, nitro, amino, alkylsulphonamido, bis(alkylsulphonyl) amino or acylamino, X is nitrogen or a >CH-radical R is a radical of formula: in which A denotes a single bond or methylene or, when X is nitrogen, A may denote carbonyl, and R2 and R3, which are identical or different, are hydrogen, halogen, hydroxy, alkyl, alkoxy, nitro, amino, alkylsulphonamido, bis(alkylsulphonyl)amino, acylamino, sulphamoyl or cyano, or, when they are adjacent, together form a methylenedioxy or ethylenedioxy radical, or else R is pyridyl or 2(2H)-benzimidazolonyl if X denotes >CH-, and R' and R'' are identical and are hydrogen or alkyl, their isomeric forms and mixtures thereof, and their acid addition salts, can be used as antiarrhythmic and antifibrillation agents.