(3S,4S)-N'-[N-3.beta.-Hydroxylup-20(29)-en-28-oyl]-8-aminooctanoyl]-4-amino-4-benzyl-3-hydroxybutyric acid 174740-58-0 AIDS-033523 AIDS033523 Benzenepentanoic acid, .beta.-hydroxy-.gamma.-[[8-[[(3.beta.)-3-hydroxy-28-oxolup-20(29)-en-28-yl]amino]-1-oxooctyl]amino]-, [S-(R*,R*)]- Betulinic acid NH-HepCONHPrCOOH deriv.