sentences:  Transition state analogs can be used as inhibitors in enzyme-catalyzed reactions by blocking the active site of the enzyme.Theory suggests that enzyme inhibitors which resembled the transition state structure would bind more tightly to the enzyme than the actual substrate.Examples of drugs that are transition state analog inhibitors include flu medications such as the neuraminidase inhibitor oseltamivir and the HIV protease inhibitors saquinavir in the treatment of AIDS.