Medicinal Chemistry and drug development reached the conclusion that natural substances and synthetic compounds are complementary as sources for new drugs.The natural compound needs to be modified synthetically to enhance its desirable medicinal properties, or to reduce its toxic properties. In present study potentially therapeutic carboxyphenyl formazans, pyrimidine formazans and quinazolinone formazans were synthesized and were characterized.All synthesized compounds were subjected for in-vitro antibacterial, in-vitro antifungal, in-vitro analgesic, in-vitro anti-inflammatory and in-vitro anthelmintic activities. This work provides excellent approach for the synthesis of pharmacologically active and important formazans derivatives.