Synthesis of Peptide Nucleic Acid Monomers Containing the Four Natural Nucleobases: Thymine, Cytosine, Adenine, and Guanine and Their Oligomerization
作者:Kim L. Dueholm、Michael Egholm、Carsten Behrens、Leif Christensen、Henrik F. Hansen、Tore Vulpius、Kenneth H. Petersen、Rolf H. Berg、Peter E. Nielsen、Ole Buchardt
DOI:10.1021/jo00098a042
日期:1994.9
The preparation of mixed-sequence PNAs (PNAs containing the four natural nucleobases; thymine, cytosine, adenine, and guanine) is described. The PNA monomers containing thymine, Cbz-protected cytosine, or adenine or benzyl-protected guanine were prepared via convergent syntheses. Subsequent to introduction of the carboxymethyl linker at N-1 of the pyrimidines or N-9 of the purines and suitable protection of exocyclic groups, the nucleobase derivatives were coupled to the Boc-protected backbone esters 10a or 10b and finally hydrolyzed affording the monomers 12a-d. The exocyclic amino groups of cytosine and adenine were protected with a benzyloxycarbonyl group. The exocyclic amino group of guanine was left unprotected whereas O-6 was protected as the benzyl ether. Two mixed-sequence 10-mers, each with five purines incorporated, and a mixed-sequence 15-mer Containing seven purines were assembled essentially following standard solid phase peptide synthesis protocols.