There are number of software such as WinMopac /Hype r chem. /Dragon etc. available commercially through which not only various derivat ives of α - aryl propanoic acid can be designed but also various physical properties and n umber of molecular descriptor can be calculated, after comparing their physical properti es and descriptors with lead compound Ibuprofen, the unknown compounds I & II are selecte d. A good synthetic rout can be predicted through mathematical modeling using particularly He ndrickson equation W= Ση iX li , Where W=Sum of Weight, η i- is number of skeletal carbons in each piece and X is reciprocal of the average yield for each step. With the help of this hypothesis, not only the activity of Non Steroidal Anti-Inflammatory Drugs (NASID) can be pr edicted especially for the new compounds but through mathematical modeling a good synthetic route can also be suggested.