1-[4-[2-(1-Methyl-1-phenyl-ethyl)-2H-tetrazol-5-yl]-phenyl]-4(S)-hydroxy-5(S)-2,5-bis[N-(N-methoxycarbonyl-(L)-tert-leucyl)amino]-6-phenyl-2-azahexane AIDS-057737 AIDS057737 Heterocyclic Azahexane deriv.