2-amino-9-[(1S,6R,8R,9R)-9-hydroxy-3-oxido-3-oxo-2,4,7-trioxa-3$l^{5}-phosphabicyclo[4.3.0]nonan-8-yl]-3H-purin-6-one 2-amino-9-[(1S,6R,8R,9R)-9-hydroxy-3-keto-3-oxido-2,4,7-trioxa-3$l^{5}-phosphabicyclo[4.3.0]nonan-8-yl]-3H-purin-6-one Guanosine cyclic 3',5'-monophosphate nchembio.2007.46-comp1 nchembio.2007.33-comp1