NC43562
3′-Guanylic acid, 2′-deoxy-5′-O-[1,14-hydroxy-14-[[(3R,4R)-4-(hydroxymethyl)-1-(phenylmethyl)-3-pyrrolidinyl]oxy]-1,14-oxido-2,9,13-trioxa-10-aza-1,14-diphosphatetradec-10-en-1-yl]guanylyloxymethylene[(3R,4R)-1-(phenylmethyl)-3,4-pyrrolidinediyl]oxyphosphinico-(3′→5′)-, cyclic ester