11-[[3.beta.-Acetoxy-28-norlup-20(29)-en-17-yl]carbamoyl]undecanoic acid 173106-46-2 AIDS-033539 AIDS033539 Betulinic acid, undecanoate deriv. Dodecanoic acid, 12-[(3.beta.)-3-hydroxy-28-norlup-20(29)-en-17-yl]-12-oxo-