4H-Furo[3,2-d]-1,3,2-dioxaphosphorin, guanosine deriv. (ZCI); Guanosine 3′,5′-phosphate (cyclic) (7CI); 3′,5′-Cyclic GMP,2-amino-9-((4aR,6R,7R,7aR)-2,7-dihydroxy-2-oxidotetrahydro-4H-furo[3,2-d][1,3,2]dioxaphosphinin-6-yl)-3H-purin-6(9H)-one,Guanosine