Ethyl (2E,4S)-4,5-isopropylidenedioxy-2-methylpent-2-enoatecan beused for the synthesis of2'-deoxy-2'-fluoro-2'-C-methylcytidine (I) (PSI-6130), which is a potent and selective inhibitor of HCV NS5B polymerase and marine dolabellane diterpenoids (ie. claenone (I), palominol (II), and dolabellatrienone (III)). It also has potential applications for the synthesis of related antiviral agents.