Boldenone undecylenate is a prodrug of boldenone, and hence is an agonist of the androgen receptor.Boldenone has strong anabolic effects and moderate androgenic effects.It also has low estrogenic activityand has little or no progestogenic activity.In relation to the fact that it is not 17α-alkylated, boldenone and boldenone undecylenate have little or no risk of hepatotoxicity.
(1R,4S,4aR,9aS)-rel-1,4,4a,9a-Tetrahydro-4a-methyl-1,4-methanoanthracene-9,10-dione is prepared by the reaction of menadione and cyclopentadiene.