Synthesis of some Novel Pyrazolo and Triazolo Quinolines from Coumarin Compounds

Coumarin and its furo derivatives (psoralene and isopsoralene) are used as precursor for preparation of heterocyclic compounds. The 4-methyl-7-mthoxycoumarin, psoralene and substituted isopsoralene (II, III and IV) which are derived from 4-methyl-7-hydroxycoumarin (I), when reacted with hydrazine hydrate through nucleophilic substitution reaction under basic condition give N-amino-2-quinolone and its furo derivatives (1,5 and 9) in good yields.
Reaction of these compounds (1,5 and 9) with methyl acetoacetate, ethyl acetoimidate or thiosemicarbazide, a new heterocyclic compounds will be formed pyrazolo-quinoline and it is furo derivatives (2,6 and 10); 1,2,4-triazolo-quinoline and its furo derivatives (3,7 and 11) and 1,2,4- triazolo-quinoline-2-thione (4,8 and 12) respectively.
The assigned structure of the prepared compounds were elucidated by the available physical and spectral methods IR, UV and 1H-NMR.