Synthesis of porphyrinyl‐nucleosides

Several porphyrinyl‐nucleosides were prepared in the reaction of the OH group of one, two or four meso‐ p ‐hydroxyphenyl substituents of porphyrin with 5′‐ O ‐tosylates of 2′,3′‐ O ‐isopropylidene‐adenosine or ‐uridine, or 5′‐ O ‐tosylthymidine; the remaining porphyrin meso‐substituents were p ‐tolyl, p ‐hydroxyphenyl or 4‐pyridyl. The following porphyrinyl‐nucleosides were obtained with 8–17% yield: meso‐di( p ‐tolyl)di( p ‐phenylene‐5′‐ O ‐2′,3′‐ O ‐isopropylidene‐adenosine) (or ‐uridine)porphyrins 1,2 , the respective meso‐tetranucleosideporphyrins 3,4 ‐meso‐mono( p ‐phenylene‐5′‐ O ‐thymidine)porphyrins 5–7 , meso‐di( p ‐tolyl)di( p ‐phenylene‐5′‐ O ‐thymidine)porphyrins 8,9 and the meso‐di( p ‐hydroxyphenyl)di( p ‐phenylene‐5′‐ O ‐thymidine)porphyrins 10. Other compounds prepared belonged to the series: meso(4‐pyridyl) 4−n ( p ‐phenylene‐5′‐ O ‐2′,3′‐ O ‐isopropylideneuridine) n porphyrin, n = 1, 2 or 4, 11–13. N ‐Methylation gave the water soluble iodide salts: ( N ‐methyl‐4‐pyridinium)4 4−n ( p ‐phenylene‐5′‐ O ‐2′,3′‐isopropylideneuridine) n porphyrins, n = 1, 2 or 4, 14–16. The ms fab showed in most cases stepwise detachment of the CH 2 (5′)‐nucleoside fragments. The porphyrins meso disubstituted by thymidine represent a convenient substrate for the build‐up of both nucleoside units into the oligo/polynucleotide chains.