AIDS-059638 AIDS059638 CNG Cyclic Cyanoguanidine deriv. Q8258 [4R-(4.alpha.,5.alpha.,6.beta.,7.beta.)]-Hexahydro-5,6-dihydroxy-1,3-bis(3-cyclobutylmethyl)-4,7-bis(phenylmethyl)-2H-1,3-diazepin-2-ylidene]cyanamide