Pteridine. Teil LXXX. Synthese, Reaktionen und Photochemie von Pteridinthionen

Abstract

Synthesis, Reactions, and Photochemistry of PteridinethionesThe pteridine-6(5H)-thione 1 and various pteridine-7(8H)-thiones (13, 22, 26) have been synthesized, and their photochemical reactivity has been investigated under aerobic conditions. The formation of different photooxidation products is pH-dependent. In acidic to neutral media, disulfides (2, 15, 23, 29) are formed, whereas neutral to alkaline solutions favour the formation of pteridinesulfinic (3, 17) and -sulfonic acids (6, 16, 24, 30). Prolonged irradiation of the disulfides 2 and 15 led to the intensively yellow fluorescing bis(thio)dilumazines 19 and 20, respectively.

Preparation and Synthetic Application of Highly Reactive 6-Trifluoromethanesulfonyloxylllmazine; A Novel Method for 6-Substituted Lumazines

“…In conclusion, compound 4 is more reactive toward nucleophilic substitution than usually employed 6-halogenolumazines 2 and 3 (15)(16)(17)(18), and variety of nucleophiles could replace the trifluoromethanesulfonyloxy group on the C( 6) position . for example, preparation of 6-aminolumazine 8 ti-om 6-chlorolumazine 2 was not effected by ammonia but by stepwise reactions using substitution by hydrazine under forcing conditions ( 15 ).…”