Enfumafungin derivative triterpenoid antifungal compounds are used to treat or prevent fungal infections occurring in or under acidic conditions where the pH is lower than about 7, due to their unexpected, enhanced efficacy under such conditions. The enfumafungin derivative triterpenoids (or pharmaceutically acceptable salts or hydrates thereof) are inhibitors of (1,3)-β- D-glucan synthesis and are useful in the treatment or prevention of yeast or mold infections that occur in anatomic areas having a low pH, such as the vaginal cavity, or under acidic local environment conditions such of those seen in fungal abscesses, empyema, or upper gastrointestinal tract infections.
