Showing papers on "Benzopyrans published in 1987"
Patent•
04 Nov 1987TL;DR: Isoflavans of the formula I ##STR1## wherein the groups OR, R', R" and ring B are as defined in the specification, exhibit valuable pharmacological properties, especially for the treatment of vascular diseases as mentioned in this paper.
Abstract: Isoflavans of the formula I ##STR1## wherein the groups OR, R', R" and ring B are as defined in the specification, exhibit valuable pharmacological properties, especially for the treatment of vascular diseases. They are prepared by methods known per se.
47 citations
Patent•
08 Dec 1987TL;DR: Herbicidal N-(heterocyclyl)-substitued benzofurans and benzopyrans of the formulae: the symbols have meanings described in the specification as discussed by the authors.
Abstract: Herbicidal N-(heterocyclyl)-substitued benzofurans and benzopyrans of the formulae:
wherein the symbols have meanings described in the specification.
15 citations
TL;DR: In this paper, the 3-methyl, n-butyl, and phenyl derivatives of 3,10b-epidioxy-2,3,4a, 10b-tetrahydro-6-methyl-1H-naphtho[2,1-b]pyran were given.
Abstract: 3,3,6,10b-Tetramethyl-4a, 10b-dihydronaphtho[2,1-e][1,2,4]trioxane and its 3,3-spirocyclic cyclopentane analogue on treatment with an excess of trimethylsilyl trifuloromethanesulphonate for 10 min at 24 °C rearrange to give 2-(2-oxopropyl)-3-methyl-1-benzofuran in high yield; in similar fashion the 3-methyl, n-butyl, and phenyl derivatives of 3,10b-epidioxy-2,3,4a,10b-tetrahydro-6-methyl-1H-naphtho[2,1-b]pyran give the 3-oxobutyl,3-oxoheptyl, and 3-phenyl-3-oxopropyl derivatives of 2-formyl-3-methyl(2H)-1-benzopyran
9 citations
9 citations
9 citations
TL;DR: The pyran ring cleaved product (3) and the tetracyclic chromene (5) were obtained by using a strong electron withdrawing group at C(6) in the benzopyran, and a conformationally mobile lactam ring.
6 citations
TL;DR: In this paper, the versatility of the new route to a substituted chromane via a lithiated allene recently described by us was reported and the relatively more stable alkynols 2−4 were readily identified and thus provide evidence for the formation of vinyl acetylene carbinol as an intermediate in the new pathway.
6 citations
TL;DR: La reaction avec les chromenes conduit principalement aux acides salicyliques, benzoiques par degradation and, en petites quantites a des flavonols as mentioned in this paper.
Abstract: La reaction avec les chromenes conduit principalement aux acides salicyliques, benzoiques par degradation et, en petites quantites a des flavonols; avec les chromannes, on obtient des flavonols
6 citations
TL;DR: In this article, a mass spectral fragmentation of 4-chloro-3-(N-aryliminomethyl) (2H) benzopyrans and benzothiopyrans was proposed.
Abstract: Intramolecular substitutions leading to cyclizations with the ejection of chlorine have been noticed during mass spectral fragmentation of 4-chloro-3-(N-aryliminomethyl) (2H) benzopyrans and benzothiopyrans. Very interesting ortho effects involving intramolecular substitutions have also been observed in 6-methyl-4-diloro-3-[N-(2-methoxyphenyliminomethyl)] (2H) benzopyran and 6-methyl-4-chloro-3-[N-(2-chlorophenyliminomethyl)]-(2H) benzopyran. The proposed fragmentation mechanisms have been supported by the accurate mass measurements and linked scan studies.
4 citations
Journal Article•
TL;DR: Synthese des composes du titre par action du malononitrile sur des arylidene-3 chromannones-4 respectivement en presence de piperidine ou de soude as discussed by the authors.
Abstract: Synthese des composes du titre par action du malononitrile sur des arylidene-3 chromannones-4 respectivement en presence de piperidine ou de soude. Mecanismes
2 citations
Journal Article•
TL;DR: The title compounds were synthesised by the condensation of ethyl alpha-propyl/isopropyl/n-butylacetoacetate (13-15) with disubstituted phenols (1-12) in presence of POCL3 or 73 percent H2SO4 as mentioned in this paper.
Abstract: The title compounds were synthesised by the condensation of ethyl alpha-propyl/isopropyl/n-butylacetoacetate (13-15) with disubstituted phenols (1-12) in presence of POCL3 or 73 percent H2SO4. Compounds 25, 27 and 39 prevented in vitro clotting of blood for 40, 120 and 30 min. respectively. In gross behavioural effects, compound 35 was found to be depressant while 36-38 were stimulants. Rest of the compounds did not show any significant activity.
Patent•
12 Mar 1987
TL;DR: In this paper, the meanings of the benzopyrans of the formula "STR1" and "STR2" are described, a process for their preparation, and their use in pressure-sensitive or heat-sensitive layers.
Abstract: Benzopyrans of the formula ##STR1## where X is a radical ##STR2## and R1, R2, R3, R4 and the ring A have the meanings stated in the description, a process for their preparation, and their use in pressure-sensitive or heat-sensitive layers.
TL;DR: In this paper, 2.2-Styryl and 2.3-pyranobenzopyrones via H-abstraction were obtained for photolysis in benzene and MeOH, respectively.
TL;DR: In this paper, the 3-methyl, n-butyl, and phenyl derivatives of 3,10b-epidioxy-2,3,4a, 10b-tetrahydro-6-methyl-1H-naphtho[2,1-b]pyran were obtained.
Abstract: 3,3,6,10b-Tetramethyl-4a, 10b-dihydronaphtho[2,1-e][1,2,4]trioxane and its 3,3-spirocyclic cyclopentane analogue on treatment with an excess of trimethylsilyl trifuloromethanesulphonate for 10 min at 24 °C rearrange to give 2-(2-oxopropyl)-3-methyl-1-benzofuran in high yield; in similar fashion the 3-methyl, n-butyl, and phenyl derivatives of 3,10b-epidioxy-2,3,4a,10b-tetrahydro-6-methyl-1H-naphtho[2,1-b]pyran give the 3-oxobutyl,3-oxoheptyl, and 3-phenyl-3-oxopropyl derivatives of 2-formyl-3-methyl(2H)-1-benzopyran.
TL;DR: Several aryl-1(3bromo-2-methyl-prop-2ene) ethers 2 have been prepared and their thermal rearrangements in PEG-400 in the presence of N,N-diethylaniline were found to yield the title compounds as discussed by the authors.
Abstract: Several aryl-1(3-bromo-2-methyl-prop-2-ene) ethers 2 have been prepared and their thermal rearrangements in PEG-400 in the presence of N,N-diethylaniline were found to yield the title compounds.
TL;DR: The pyran ring cleaved product (3) and the tetracyclic chromene (5) were obtained by using a strong electron withdrawing group at C(6) in the benzopyran, and a conformationally mobile lactam ring as discussed by the authors.
Abstract: The title reactions furnished the pyran ring cleaved product (3) and the tetracyclic chromene (5), rather than the expected 4-cyclicamido-3-hydroxy benzopyrans (1,RCN and NO 2 , respectively, n=11). Mechanisms proposed for these reactions require a strong electron withdrawing group at C(6) in the benzopyran, and a conformationally mobile lactam ring.