[Oligoadenylate 4-(N-2-chloroethyl-N-methylamino) benzylidene 5'-phosphamides complex formation with DNA by...

Alkylating derivatives of oligoadenylate 5'-phosphamides CIRCH2NH(pA)n n=4-7 attach to complementary regions of denatured E. coli DNA. Apparent binding constants Kapp are evaluated from plots of binding at 0 degrees obtained by equilibrium dialysis. Kapp of CIRCH2NH(pA)7 is shown to be similar to that of (Ap)5ARCl-benzylidene derivatives of hexaadenylate; Kapp both of them differ from Kapp of hexaadenylate only slightly. Under saturation conditions CIRCH2(Ap)7 binds to 24 sites per 10 kilobases of E. coli DNA. Macrostructure of denatured DNA is changed in the course of binding and number of burned complementary sites becomes exposed to following binding with the oligomer.