Synthesis and Antiviral Activities of New Pyrazolo[4,3‐<i>c</i>]quinolin‐3‐ones and Their Ribonucleoside Derivatives

Abstract

Several new pyrazolo[4,3-c]quinolin-3-one ribonucleosides (5a-g) and their corresponding heterocycle moieties (3a-g) were synthesized and evaluated against vaccinia virus (VV) and herpes simplex virus type 1 (HSV-1). The derivatives 3c and 3d showed modest inhibitory activity against vaccinia virus reaching 70% at a concentration of 100 microM. All heterocyclic compounds (3a-f) showed a modest inhibition against HSV-1, reaching the maximal inhibitory effect around 20-30%. The antiviral effects of most of the pyrazolo[4,3-c]quinolin-3-one ribonucleosides (5a-f) on VV and HSV were not impressive.