反铂与鸟苷配位对G-C碱基对间氢键的影响

Effects of trans-[Pt(NH_3)_2Cl_2]on the Hydrogen Bonds Between Guanosine and Cytidine

本文在不同 pH 条件下研究了反铂与鸟苷的相互作用,析出了不同结合方式的配合物,并作了表征.用^(13)C 和~1H NMR 研究反铂与鸟苷不同方式的结合对 G-C 碱基对氢键的影响时发现,反铂结合于鸟嘌呤的 N(7)对 G-C 配对能力有一定削弱,但不能完全阻断 G-C 配对,只有当反铂和鸟嘌呤的 N(7)配位,同时 N(1)脱质子时才有可能完全中断 G-C 配位.

The interactions of trans-[Pt(NH_3)_2Cl_2] (trans-DDP) with guanosine in differentpH conditions have been studied and four new complexes,trans-[Pt(NH_3)_2(Guo)-(NO_3)] NO_3 (pH=3),trans-[Pt(NH_3)_2(Guo)_2]NO_3(pH=5),trans-[Pt(NH_3)_2(GuoH_(-1))_2]and trans-[Pt(NH_3)_2(GuoH_(-1))(NO_3)] in pH=7,have been synthesized and characterizedby IR and NMR.The effects of trans-DDP on the hydrogen bonds between guanosineand cytidine have been studied by means of ^(13)C and ~1H NMR.It is discovered that thecoordination of trans-DDP to N(7) guanosine only weakens the hydrogen bonds betweenguanosine and cytidine and can't break the hydrogen bonds.However,when trans-DDP is bonded to deprotonated N(1) guanosine through N(7),the hydrogen bonds ofG-C base pair are all prevented.