Anabolicum Vister (quinbolone) is a prodrug of boldenone. It is the exact same molecule but with a cyclopentenyl ether modification at the 17beta hydroxy position. Unlike the ester modifications at the 17 position commonly used for injectable anabolic steroids, this modification provides enhanced oral bioavailability.
As with esterified compounds, the Anabolicum Vister molecule is not active in its modified form, and becomes effective only when the cyclopentenyl ether group is metabolically removed, yielding boldenone. At this point, properties are the same as boldenone delivered via de-esterification of injected boldenone undecylenate or other boldenone ester. The duration of action of this oral form is almost undoubtedly much shorter, however.
Quinbolone is not very potent (effective per milligram) compared to injected boldenone undecylenate (Equipoise) or any injected anabolic steroids, or to most oral anabolic steroids. I know of no athletes who use this product.
Quinbolone is the chemical name of active ingredient in Anabolicum Vister. Anabolicum Vister was a registered trademark of Parke Davis (Italy) in the United States and/or other countries prior to cancellation.