Synfacts 2007(3): 0335-0335  
DOI: 10.1055/s-2007-968224
Polymer-Supported Synthesis
© Georg Thieme Verlag Stuttgart · New York

Solid-Phase Synthesis of N-9-Substituted 2,8-Diaminopurines

Contributor(s): Yasuhiro Uozumi, Toshimasa Suzuka
A. G. Cole*, A. Metzger, G. Ahmed, M.-R. Brescia, R. J. Chan, J. Wen, L. O’Brien, L.-Y. Qin, I. Henderson
Pharmacopeia Drug Discovery, Princeton, USA
Further Information

Publication History

Publication Date:
20 February 2007 (online)

Significance

N-9-Substituted 2,8-diaminopurines 7 were prepared in several steps starting from aldehyde 1 anchored on the resin. Thus, the resin-bound secondary amines 2 were obtained via reductive alkylation of primary amines (R1NH2) with 1 using Na(OAc)3BH. N-Arylation of amines 2 with 8, followed by the reduction of nitro group of the resulting resin-bound 5-nitro-pyrimidines 3 with Na2S4O4, gave triaminopyrimi­dines 4. Alkyl thioureas 5 were obtained via the reaction of 4 with alkyl isothiocyanates and subsequently transformed into 6 using DIC in DMF-EtOH. After TFA-mediated cleavage from the solid support, the 8-alkyl diaminopurines 7a-c were obtained in 54-89% yield with 77-88% purity.