Synthesis of New Heterocyclic Compounds Derived from 4-Amino Antipyrine

Abstract

In this work, isondoline -1,3-dione derivatives [2-5] were prepared from the
corresponding anhydrides and 4-amino antipyrine [1].Derivatives[6-11] containing urea
and thioureamoieties at position [4]were prepared from 4-amino antipyrine[1] and an
appropriatearyl or alkyliso or (isothio)cyanates and then converted into pyrimidine
derivatives [12-15].
Treatment of compound [1] with formic acid or acetic acid give the amide derivatives [16
and 17], which upon refluxing of compound [16]) with hydrazine hydrate in ethanol
yielded the corresponding 2,3-dimethyl-1-phenyl-2,4-dihydro-1H-pyrazolo[4,3,e][1,2,4]-
triazine [18].
Reacting compound [1] with acetyl acetone in boiling ethanol for 6hrs,
leads to 4-amino antipyrine derivative [19]. The azomethines[20-22] were prepared from
the corresponding aryl aldehydes and compound [1].