Abstract As an extension of a previous work, in which a series of 4-phenyl-2-thioxo-benzo [4, 5] thieno [2, 3-d] pyrimidines were synthesized, a new series of 3-amino derivatives of this ring system has been prepared. The products obtained together with those reported in the previous paper, were tested for analgesic, antipyretic and anti-inflammatory activities as well as for acute toxicity. Since these compounds could be useful for the treatment of ...