作者:Khairuzzaman B. Mullah、Wesley G. Bentrude
DOI:10.1021/jo00026a008
日期:1991.12
The recently discovered photo-Arbuzov rearrangement was carried out with a series of tert-butyldimethyl-silyl-protected dimethyl benzyl phosphites, 9, 15, 18, 20, and 22, easily derived from alcohol precursors, to afford the corresponding dimethyl benzylphosphonates in 67-74% isolated yields. One of the phosphonates, 10, was further converted to the primary bromide which underwent reaction with the sodium salts of adenine, cytosine, and 2-amino-6-chloropurine to give the desired N-alkylated acyclic nucleoside dimethyl benzylphosphonates. The 2-amino-6-chloro compound was further elaborated to the guaninyl and 2,6-diamino derivatives. Demethylation afforded the acyclic nucleoside-based benzylphosphonic acids 25, 27, 29, 31, and 32 in good overall yields. These molecules are closely related structurally to the active antiviral 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA) and the potent human erythrocyte purine nucleoside phosphorylase (PNP) inhibitors 9-(5-phosphonopentyl)guanine and 9-(5,5-difluoro-5-phosphonopentyl)guanine.