3'-Guanylic acid, 5'-O-(bis(4-methoxyphenyl)phenylmethyl)-P-(4-chlorophenyl)-2'-deoxy-N-(2-methyl-1-oxopropyl)guanylyl-(3'.5')-2'-deoxy-N-(2-methyl-1-oxopropyl)-, 4-chlorophenyl 2-cyanoethyl ester