Chromones 4H-l-benzopyran-4-ones

H-l-Benzopyran-4-ones — see Chromones 4H-l-Benzopyran-4-ones, 2-phenyl — see Flavones Benzopyranopyrazoles synthesis, S, 317, 341 Benzopyrano[4,3-c]pytazol-4-one synthesis, 3, 712 Benzopyrano[4,3-6]pyridine synthesis, 3, 712 Benzopyrano[4,3-ii]pyrimidine synthesis, 3, 712 Benzopyrans nomenclature, 1, 23 pyrylium salt synthesis from, 3, 873 reactions... 

The chromones (4H-l-benzopyran-4-ones) have been reported to exhibit antifungal, antiviral, antimicrobial, antiallergic, antitublin, and antitumor activ-... 

In contrast to the benzoannelated nitrogen heterocycles, only a few kinds of benzoannelated systems without nitrogen have been described (Fig. 3.15). Five-mem-bered rings such as benzo[b]furans (336) [184, 461] and hydrobenzo[b]furans (337) (Scheme 3.41) [337, 462, 463] and six-membered rings like 4H-l-benzopyran-4-ones (4-chromones) (338) and 2H-l-benzopyran-2-ones (coumarines) (339) [96, 464, 465] 2,3-dihydro-4H-l-benzopyran-4-ones (chroman-4-ones) (340) [466] and 3,4-dihydro-lH-2-benzopyrans (isochromans) (341) [444] have been reported. 

Updated Entry replacing B-60006 3-(l, 3-Benzodioxol-5-yl)- 7-hydroxy-4H-l-benzopyran-4-one, 9CI. 7-Hydroxy-3- 3,4-methylenedioxyphenyl)chromone. Pseudobaptigenin. xp-Baptigenin [90-29-9]... 

Important derivatives of 4H-chromene are chromone (8, 4H-l-benzopyran-4-one), flavone (9, 2-phenyl-4H-l-benzopyran-4-one), and xanthene (10), which are discussed in Section 6.12. 

Methylenebis-(4,5,6-trihydroxy-3,1 -phenylene)]bis-l-propanone, 2120 4 -Hydroxy-3 ",5 -dimethoxy-3, 4 "-oxydipropiophenone. l-[4-Hydroxy-3-methoxy-5-[2-methoxy-4-( 1 -oxopropyOphenoxyJphenyl]-l -propanone, 2122 7-Hydroxy-2,3-dimethyl-8-(l-oxopropyl)chromone. 7-Hydroxy-2,3-dimethyl-8-(1 -oxopropyl)-4H-l-benzopyran-4-one, 2142... 

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