(3R,S)-N'-[N-3.beta.-Hydroxylup-20(29)-en-28-oyl]-8-aminooctanoyl]-3-aminobutyric acid 174740-52-4 AIDS-033509 AIDS033509 Betulinic acid NH-HepCONHEtCOOH deriv. Butanoic acid, 3-[[8-[[(3.beta.)-3-hydroxy-28-oxolup-20(29)-en-28-yl]amino]-1-oxooctyl]amino]-