Fig. 3: Substrate scope of the adenosine and its analogues.

aGeneral conditions: adenosine analogue (1.0 equiv.), NHPI ester (1.2 equiv.), Ru(bpy)3(PF6)2 (1 mol%), Cu(MeCN)4PF6 (50 mol%), and Et3N (2.5 equiv.) in dry DMA (0.05 M) on 0.2 mmol scale; irradiated by 20 W blue LED *2 at r.t. for 20 h; isolated yield. badenosine analogue (1.0 equiv.), NHPI ester (1.2 equiv.), Ru(bpy)3(PF6)2 (1 mol%), Cu(MeCN)4PF6 (50 mol%), dibutyl phosphate (1.5 equiv.), and Et3N (2.5 equiv.) in dry DMA (0.05 M) on 0.2 mmol scale; irradiated by 20 W blue LED *2 at r.t. for 12 h; isolated yield. cadenosine analogue (1.0 equiv.), NHPI ester (1.2 equiv.), Ru(bpy)3(PF6)2 (1 mol%), Cu(MeCN)4PF6 (50 mol%), dibutyl phosphate (1.5 equiv.), H2O (150.0 equiv.) and Et3N (4.0 equiv.) in DMA (0.05 M) on 0.2 mmol scale; irradiated by 20 W blue LED *2 at r.t. for 12 h; isolated yield. dAdenosine analogue (1.0 equiv.), TMSCl (4.0 equiv.), BDMAMH·2 HCl (3.5 equiv.) in pyricdine (1 mL, 0.15 M) on 0.15 mmol scale, stirred for 24 h at 100 °C. The mixture was cooled to r.t., TMSCl (3.4 equiv.) was added and stirring was continued for 15 min. 4ea 6-(1,2,4-triazol-4-yl)purine cordycepin, 4fa 6-(1,2,4-triazol-4-yl)purine ddA, 4ua 6-(1,2,4-triazol-4-yl)purine adefovir dipivoxil, 4va 6-(1,2,4-triazol-4-yl)purine Remdesivir, DMTr 4,4′-dimethoxytrityl, HSV herpes simplex virus, HBV hepatitis B virus, COVID-19 coronavirus disease 2019.