Interferon inducing activities of derivatives of 1,3-dimethyl-4-(3-dimethylaminopropylamino)-1H-pyrazolo(3,4-b)quinoline and related compounds.

Syntheses and interferon inducing acitivites are reported for 137 relatives of 1,3-dimethyl-4-(3-dimethylamino-propylamino)-1H-pyrazolo[3,4-b]quinoline (1). Three different generalized synthetic schemes for the preparation of pyrazolo[3,4-b]quinolines are presented and limitations contrasted. Other heterocyclic nuclei containing the 3-dimethylaminopropylamino side chain include pyridine, quinoline, acridine, pyrazolo[3,4-b]pyridine, pyrazolo[3,4-B][1,8]naphthyridine, pyrazolo[4',3':5,6]pyrido[2,3-d]pyrimidine, dipyrazolo[3,4-b:4',3'-e]pyridine, pyrrolo-[2,3-b]quinoline, isothiazolo[5,4-b]quinoline, and pyrido[2,3-h]pyrazolo[3,4-b]quinoline. Structural requirements for interferon induction in this series are discussed and two of the more active compounds (172 and 196) are compared directly with tilorone.