Nucleic Acids Research, 1983, Vol. 11, No. 10 3393-3404
© 1983
CHEMISTRY |
Specifically alkylated DNA fragments. Synthesis and Physical Characterization of D[cGC(o2Me)GCG]and d[cGT(O6Me) GCG]
Department of Chemistry Rutgers-The State University of New Jersey New Brunswick, NJ 08903 USA
Received March 14, 1983. Revised April 26, 1983. Accepted April 26, 1983.
Two hexamer DNA fragments containing a carcinogenic modified base, 06-methyl guanine, have been synthesized by a solid-phase phosphotriester method, in which the unmodified guanine residues present were 0o protected with the 4-nitrophenylethyl group. These two alkylated oligonucleotides were found to have similar Tm's about 40o lower than the unmodified parent compound, d(CG)3. Moreover, the presence of the (06Me)G appears to inhibit the B+Z transition, as determined by CD spectroscopy