Synthesis and antimicrobial activity of some coumarin derivatives
E.E.rashi N.M.A.; Nasef, A.M.M.; Magd, E.D.n A.A.; Atalla, M.M.
Egyptian Journal of Pharmaceutical Sciences 27(1-4): 7-16
3 Hydroxycoumarin (Ia) reacts with amines without a solvent to form the corresponding 3-arylaminocoumarins (IIa-e). 4-Bromo-3-hydroxycoumarin (Ib) gives with aromatic amines 4-arylamino-3-hydroxycoumarins (Ic-g). On the other hand, when 3-hydroxycoumarin (Ia) was treated with amines in presence of formalin the respective 4-substituted aminomethyl-3-hydroxycoumarins (IVa-c) were obtained. Condensation of 3-hydroxycoumarin (Ia) with aromatic amines and paraformaldehyde led to the formation of 7-oxo (1)benzopyrano(3,4-b) quinolines (Va-c). 3-Hydroxycoumarin (Ia) reacts with phenyl isocyanate to form 4-(phenyl-carbamoyl)-3-hydroxycoumarin (VIa). On the other hand, alkyl isocyanates yield the corresponding carbamates (VId and VIe). 4-Bromo-3-hydroxycoumarin (Ib) yields the corresponding 4-bromo carbamate derivative (VIg) upon treatment with iso propyl isocyanate. The antimicrobial activity of the new compounds was tested on Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Candida utilis and Aspergillus niger.