| abstract |
The novel positively charged pro-drugs of diclofenac in the general formula(1) 'Structure 1' were designed and synthesized. The compounds of the general formula(1) 'Structure 1' indicated above can be prepared from functional derivatives of diclofenac (for example acid halides or mixed anhydrides), by reaction with suitable alcohols, thiols, or amines. The positively charged amino groups of these pro-drugs not only largely increases the solubility of the drugs in water, but also bonds to the negative charge on the phosphate head group of membranes and push the pro-drug into the cytosol. The experiment results suggest that the pro-drug, diethylaminoethyl 2[(2,6-dichlorophenyl)amino]benzene acetate.AcOH diffuses through human skin ~250 times faster than do 2[(2,6-dichlorophenyl)amino]benzene acetic acid (diclofenac) and ethyl 2[(2,6-dichlorophenyl)amino]benzene acetate. In plasma, more than 90% of these pro-drugs can change back to the drug in a few minutes. The prodrugs can be used medicinally in treating any diclofenac-treatable conditions in humans or animals and be administered not only orally, but also transdermally for any kind of medical treatments and avoid most of the side effects of diclofenac, most notably GI disturbances such as dyspepsia, gastroduodenal bleeding, gastric ulcerations, and gastritis. Controlled transdermal administration systems of the prodrug enables the diclofenac to reach constantly optimal therapeutic blood levels to increase effectiveness and reduce the side effects of diclofenac. |