Structural modifications of the existing ampicillin are much needed for saving patients from ampicillin-resistant microorganisms. A number of new molecules were generated by side chain modification of the existing ampicillin structure. Armed with molecular docking softwares like FlexiDOC, GLIDE, and AutoDOCK, a docking study was performed. Interaction between new molecules and target protein (1W2N) was also executed. Finally, we arranged new molecules according to docking scores, which directly reflects the binding affinity to the receptor protein.