Carbocyclic NA inhibitors

Syntheses of the Prototypes In their initial stage of designing carbocyclic NA inhibitors, the oleflnic isomers that are shown in structures 109 (Type [I]) and 110 (Type [II]) were considered as two possible prototypes of transition-state analogues. The isomer 109 is structurally closer to transition-state 108 than isomer 110. However, Gilead s group expected that it would be... 

It was concluded that this result demonstrated that the double bond position in the design of carbocyclic NA inhibitors plays an important role in NA activity however, further structural investigation is required to illustrate the binding differences of 109a and 110a in the NA active site. Eventually, based on this result, the stmcture of 109 was selected as the prototype for further drug discovery attempts. 

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