Topic
Benzopyran
About: Benzopyran is a research topic. Over the lifetime, 1889 publications have been published within this topic receiving 15235 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper, the PMR spectra of four 6a,11a-dihydro-6H-benzofuro derivatives have been analyzed and the conformation of the heterocyclic rings has been derived from the vicinal coupling constants.
88 citations
TL;DR: In this paper, the photoinduced ring-opening process in spiropyran compounds has been modeled through CASSCF calculations on the lowest excited state (S1) of benzopyran.
Abstract: The photoinduced ring-opening process in spiropyran compounds has been modeled through CASSCF calculations on the lowest excited state (S1) of benzopyran. The documented S1 reaction coordinate is characterized by a ring-opening transition state connecting a cyclic intermediate to a much more stable acyclic structure. Remarkably this structure does not correspond to a real S1 intermediate but to a crossing point (i.e., a conical intersection) between the excited- and ground-state energy surfaces. At this crossing the excited-state system can undergo fully efficient decay to S0. Using the parent pyran molecule as a model, we have characterized two ground-state valleys which develop from the crossing point. The first valley leads to reactant (pyran) regeneration. The second valley leads to cZc-penta-2,4-dienal indicating that the primary ring-opened photoproduct is formed in an unstable conformation. The benzopyran/pyran reaction coordinates suggest that the first step in the benzospiropyran photochromic rea...
84 citations
TL;DR: Among the reported compounds, 1'-benzyl-3,4-dihydrospiro[[2]benzopyran-1,4'-piperidine]-3-carbonitrile 5 represents the most potent s Sigma(1) receptor ligand with a K(i) value of 1.54 nM and a sigma(1)/sigma(2) selectivity ratio of 1030.
Abstract: Several spiro[[2]benzopyran-1,4‘-piperidines] and spiro[[2]benzofuran-1,4‘-piperidines] were synthesized and evaluated for their binding properties for σ1 and σ2 receptors. The key step for the introduction of a one carbon residue is the reaction of the cyclic methyl acetals 2a and 3a with trimethylsilyl cyanide to yield the nitriles 5 and 20. The reaction of the lactols 2b and 3b with stabilized phosphoranes affords spiropiperidines with a two carbon residue in position 3. In agreement with previously reported σ1 and σ2 receptor binding data, the investigated spiro compounds display higher affinity for σ1 vs σ2 receptors. Compounds with a cyano group in position 3 of the spirocycle show high σ1 receptor affinity and selectivity. The spirobenzopyran nitrile 5 and the homologous spirobenzofuran nitriles 20 and 23 show almost identical σ1 affinities, whereas the spirobenzopyran nitrile 13 with a methylene spacer is 10-fold less potent. Among the reported compounds, 1‘-benzyl-3,4-dihydrospiro[[2]benzopyran-1...
84 citations
84 citations
Patent•
18 Jan 1996TL;DR: In this paper, the authors proposed a method for the inhibition of platelet aggregation using six membered rings of a bicyclic compound, such as benzopyran, iso-quinoline, isoquinoline or tetrahydronaphthalene.
Abstract: This invention relates to certain bicyclic compounds having a nucleus formed of two fused six membered rings, for example, benzopyran, isoquinoline, isoquinolone, tetrahydronaphthalene, dihydronaphthalene, or tetralone, substituted with both basic and acidic functionality, which are useful in inhibition of platelet aggregation.
80 citations