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Synthesis of Chromanes and 4H-Chromenes: Exploring the Oxidation of 2H-Chromenes and Dihydro-1-benzoxepines by Hypervalent Iodine(III)
(GEORG THIEME VERLAG KGSTUTTGART, 2012)
The reaction of various oxygen-containing benzo-fused cycloalkenes were studied with the hypervalent iodine reagent hydroxy(tosyloxy) iodo]benzene [PhI(OH)OTs, HTIB]. 2H-Chromene and 4-methyl-2H-chromene resulted in ...
Intraspecific variability of dihydrochalcone, chromenes and benzoic acid derivatives in leaves of Piper aduncum L. (Piperaceae)
(2009-05-18)
Chemical analysis carried out in leaves of 18 specimens of Piper aduncum L. (Piperaceae) occurring at Ripasa Reserve, Araraquara, SP, Brazil indicated two distinct populations when investigated over a period of 14 months ...
Intraspecific variability of dihydrochalcone, chromenes and benzoic acid derivatives in leaves of Piper aduncum L. (Piperaceae)
(2009-05-18)
Chemical analysis carried out in leaves of 18 specimens of Piper aduncum L. (Piperaceae) occurring at Ripasa Reserve, Araraquara, SP, Brazil indicated two distinct populations when investigated over a period of 14 months ...
Natural chromenes and chromene derivatives as potential anti-trypanosomal agents
(2008-03-01)
The aim of the study was to investigate the anti-trypanocidal activities of natural chromene and chromene derivatives. Five chromenes were isolated from Piper gaudichaudianum and P. aduncum, and a further seven derivatives ...
Natural chromenes and chromene derivatives as potential anti-trypanosomal agents
(2008-03-01)
The aim of the study was to investigate the anti-trypanocidal activities of natural chromene and chromene derivatives. Five chromenes were isolated from Piper gaudichaudianum and P. aduncum, and a further seven derivatives ...
New method for the synthesis of chromeno[4,3-b]chromene derivatives via multicomponent reaction promoted by niobium pentachloride
(2017-01-01)
Chromeno[4,3-b]chromene derivatives were synthesized from multicomponent reaction between 4-hydroxycoumarin, aryl aldehyde derivatives and 1,3-cyclohexanedione promoted by niobium pentachloride. This new method is simple, ...
Synthesis of 4H-chromenes promoted by NbCl<inf>5</inf> through multicomponent reaction
(2015-06-25)
Abstract Multicomponent reactions between phenols, β-ketoesters, and benzaldehydes for the synthesis of 4H-chromenes derivatives promoted by niobium pentachloride (NbCl<inf>5</inf>) were carried out, providing good yields ...
A chromene and prenylated benzoic acid from Piper aduncum
(Elsevier B.V., 1999-08-01)
In addition to nerolidol, 2',6'-dihydroxy-4'-methoxydihydrochalcone, methyl 2,2-dimethyl-8-(3'-methyl-2'-butenyl)-2H-1-chromene-6-carboxylate, methyl 2,2-dimethyl-2H-1-chromene-6-carboxylate and methyl 8-hydroxy-2,2-dime ...