Impurities identified by R.L. Fine Chemical, Bangalore, during the manufacturing of bulk drugs like opipramol, pargeverine and propiverine were synthesized and characterized by various analytical techniques such as TLC, FTIR, 1H-MNR, FABMS and Elemental analysis. Impurities (1a-e) were synthesized as per scheme 1 which were identified during manufacturing of opipramol bulk drug and screened for their anti-anxiety activity by elevated plus-maze method. The pharmacological screening showed that impurities (1a-e) have good anti-anxiety activity comparable to diazepam and opipramol. The other impurities (1f-i), structurally similar to pargeverine and propiverine were synthesized by scheme 2 and evaluated for their antispasmodic activity using pargeverine and propiverine as standard drug. Pharmacological methods involve the in vitro antispasmodic activity studies on a freshly removed guinea pig ileum using a force displacement transducer amplifier connected to a physiograph. Among the synthesized impurities (1f-i) in the present study, a promising compound 1g, a potent muscle relaxant as compared to standard drugs was obtained.