Chromium trioxide oxidation of 3β-acetoxy-5α-lanostane (IVa) has been evaluated as a route to 3β-acetoxy-20-oxo-4, 4, 14α-trimethyl-5α-pregnane (VI) and 3β-acetoxy-17-oxo-4, 4, 14-α-trimethyl-5α-androstane (VIIa). One of the principal oxidation products was 3β-acetoxy- 25-oxo-5α-27-norlanostane (V). Transformation of 25-ketone V to 3β, 24-dihydroxy-4, 4, 14α- trimethyl-5α-cholane (VIIIa) confirmed the structural assignment. Although small amounts ...
![[(3S,5S,8R,9S,10S,13R,14S,17R)-4,4,10,13,14-pentamethyl-17-[(2R)-6-methylheptan-2-yl]-2,3,5,6,7,8,9,11,12,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-3-yl] acetate结构式](https://image.chemsrc.com/caspic/243/6562-14-7.png)
