(4.alpha.,5.alpha.,6.beta.,7.beta.)-3,3'-[[Tetrahydro-5,6-dihydroxy-2-oxo-4,7-bis(phenylmethyl)-1H-1,3(2H)-diyl]bis(methylene)]bis[N-2-pyridinylbenzamide] AIDS-057001 AIDS057001 Cyclic urea deriv.