Novel Fused and Spiro Heterocyclic Compounds Derived from 4-(4-Amino-5-Mercapto-4H-1,2,4-Triazol-3-yl)Phthalazin-1(2H)-One

Abstract

Some new fused heterocyclic systems such as 1,2,4-triazolo[3,4-b]1,3,4-thiadiazoles and 1,3,4-thiadiazines were synthesized through the reaction of the starting material 4-(4-amino-5-mercapto-4 H -1,2,4-triazol-3-yl)phthalazin-1(2 H )-one with triethyl orthoformate, furoyl chloride, thiophene-2-aldehyde, phenylisothiocyanate, chloro acetonitrile, and p-nitro- w -bromo-acetophenone. Also spiro systems were achieved from reaction of the starting compound with isatine, and fluorenone. The newly synthesized 1,3,4-thiadiazoles and 1,3,4-thiadiazines were obtained in good yields and their structures were elucidated by spectral data and elemental analysis.