Defined Dimensional Changes in Purine Analogues

155 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1980.Pyrazolo{4,3-g}quinazolin-5-one (lin-benzoallopurinol), an extended analogue of 4-hydroxypyrazolo{3,4-d}pyrimidine (allopurinol), and pyrazolo{3,4-f}quinazolin-9-one (proxbenzoisoallopurinol), an extended analogue of 7-hydroxypyrazolo{4,3-d}pyrimidine (isoallopurinol), have been synthesized. The proximal compound has been synthesized by two independent routes. Both benzo-compounds, prepared by the elaboration of suitably substituted indazoles or quinazolines, were found to be active substrates for and alternative-substrate inhibitors of xanthine oxidase. In each case, the product of enzymatic oxidation has been isolated and compared with the same material synthesized chemically. These oxidation products have been identified as the corresponding benzoalloxanthines.A synthetic route toward the synthesis of 4-amino-8-(beta)-D-ribofuranosylpyrrolo{3,2-g}quinazoline (lin-benzotubercidin), an extended analogue of the naturally occurring Streptomyces antibiotic 4-amino-7-(beta)-D-ribofuranosylpyrrolo{2,3-d}pyrimidine (tubercidin), has been explored with the synthesis of 8-(beta)-D-ribofuranosylpyrrolo{3,2-g}quinazolin-4-one (1-deaza-lin-benzoinosine) via the "indoline-indole" method. Pyrrolino{3,2-g}quinazolin-4-one, synthesized from indoline, condensed with 5-O-tritylribose to form 8-(5'-O-tritylribofuranosyl)pyrrolino{3,2-g}quinazolin-4-one. This riboside was protected, oxidized to the pyrrolo derivative with 2,3-dichloro-5,6-dicyano-1,4-quinone (DDQ), and deprotected to give 1-deaza-lin-benzoinosine. This route seems applicable to the synthesis of lin-benzotubercidin.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD