ChemInform Abstract: SYNTHESIS AND BIOLOGICAL ACTIVITY OF SOME COUMARIN AND FUROCOUMARIN DERIVATIVES

Synthesis of 4-aminopolymethoxycoumarins from 4-hydroxycoumarin triflates

“…The reactions with 4 hydroxy analogs instead of 4 halocoumarins give considerable amounts of phenolic compounds as by products. 12 It should be noted that all these methods are appli cable only to reactions of coumarins with primary amines and require the use of a considerable excess of amine (the amine : coumarin ratio should be 10 : 1-20 : 1). As a rule, the reactions are performed in glacial acetic acid, and isolation of the target products is a laborious pro cedure.…”

Convenient Replacement of the Hydroxy by an Amino Group in 4 Hydroxycoumarin and 4-Hydroxy-6-methyl-2-pyrone under Microwave Irradiation

“…The action of primary aromatic, arylaliphatic and aliphatic amines on 4-hydroxycoumarin (1) (Scheme 1) results in the formation of N-substituted 4-aminocoumarins [2][3][4]. The latter compounds have also been prepared by the reaction of 4-halogenocoumarins with amines together with (o-hydroxyphenyl)propiolamide by-products formed by opening of the α-pyrone ring followed by elimination of hydrogen halogenide [5].…”

“…The latter compounds have also been prepared by the reaction of 4-halogenocoumarins with amines together with (o-hydroxyphenyl)propiolamide by-products formed by opening of the α-pyrone ring followed by elimination of hydrogen halogenide [5]. It was also found that refluxing 1 in an excess of amine 2, in the presence or absence of a solvent, yielded a mixture of the corresponding ring-opened phenol and 3 [2]. However, only the target 4-aminocoumarins have been successfully obtained in many cases [4].…”

“…However, only the target 4-aminocoumarins have been successfully obtained in many cases [4]. Some of the prepared compounds of type 3 showed antimicrobial activity [2]. It was recently reported that refluxing 1 in glacial acetic acid with an excess of primary amine prevented lactone ring opening and increased the yield [3].…”