2-Quin-CO(Asn)Phe Epoxy deriv. AIDS-051431 AIDS051431 [(2S,3R)-3-((S)-1-{3-Carbamoyl-2-[(1-quinolin-2-yl-methanoyl)-amino]-propanoylamino}-2-phenyl-ethyl)-oxiranylmethyl]-carbamic acid tert-butyl ester