guanosine carbamate ester methyl ester wybutosine PMID:19287006 PMID:17150819 PMID:20423905 PMID:19717466 CHEBI:46574 PMID:21670254 PMID:17727881 PMID:16005430 PMID:16642040 PMID:20382657 A nucleoside analogue having methyl (2S)-4-(4,6-dimethyl-9-oxo-4,9-dihydro-3H-imidazo[1,2-a]purin-7-yl)-2-[(methoxycarbonyl)amino]butanoate as the modified nucleobase. PMID:20972222 PMID:21917924 Reaxys:4625655 chebi_ontology PMID:11964003 yw nucleoside analogue