Purines.<b>XIV</b>. Synthesis and properties of 8-nitroxanthine and its<i>N</i>-methyl derivatives
作者:Mosselhi A. Mosselhi、Wolfgang Pfleiderer
DOI:10.1002/jhet.5570300509
日期:1993.10
Xanthine (1) and itsN-methylderivatives 2–16 have been nitrated to the corresponding 8-nitro derivatives 17–32 under different reaction conditions. Nitration in glacial acetic acid with nitric acid works well with the N-7 unsubstituted and some of the 9-methylxanthines, respectively, whereas the 7-methylxanthine derivatives react best with nitronium tetrafluoroborate in sulfolane or glacial acetic
Nucleosides 9: Design and synthesis of new 8-nitro and 8-amino xanthine nucleosides of expected biological activity
作者:Mosselhi A. N. M. Mohamed、Laila M. B. Abu-Alola、Nada M. G. Aljaied
DOI:10.1080/15257770.2017.1395036
日期:2017.12.2
5-tri-O-benzoyl-β-D-ribofuranose afforded the corresponding protected nucleosides, respectively. Nitration of each of the theophylline and 3-benzy-1-methyllxanthine protected nucleosides yielded the corresponding 8-nitronucleosides derivatives, which were reduced to give the corresponding 8-aminonucleoside derivatives. Debenzoylation of protected nucleosides formed by using methanolic sodium methoxide afforded the
Efficient synthesis of 1,3,7-substituted xanthines by a safety-catch protection strategy
作者:Matthew B. Allwood、Booma Cannan、Daan M.F. van Aalten、Ian M. Eggleston
DOI:10.1016/j.tet.2007.09.067
日期:2007.12
An efficient synthesis of selectively N-substituted xanthine derivatives is described. Cyclocondensation of a suitably protected ammoimidazole with methyl-2-phenylthioethyl carbamate, followed by oxidation of sulfur to the sulfone, provides access to an orthogonally 1,7-protected xanthine, which may then be regioselectively alkylated and deprotected under mild conditions. (c) 2007 Elsevier Ltd. All rights reserved.