Density Functional Study of the In-Line Mechanism of Methanolysis of Cyclic Phosphate and Thiophosphate Esters in Solution:  Insight into Thio Effects in RNA Transesterification

2005 ◽  
Vol 109 (42) ◽  
pp. 19987-20003 ◽  
Author(s):  
Yun Liu ◽  
Brent A. Gregersen ◽  
Xabier Lopez ◽  
Darrin M. York
Keyword(s):  
Density Functional ◽  
Functional Study ◽  
Density Functional Study ◽  
Cyclic Phosphate ◽  
Insight Into

Molecular Structure and Bonding in Platinum-Picoline Anticancer Complex: Density Functional Study

2004 ◽  
Vol 69 (1) ◽  
pp. 63-72 ◽  
Author(s):  
Danuta Michalska ◽  
Rafał Wysokiński
Keyword(s):  
Molecular Structure ◽  
Steric Hindrance ◽  
Density Functional ◽  
Anticancer Agent ◽  
Basis Set ◽  
Functional Study ◽  
Molecular Plane ◽  
Density Functional Study ◽  
Donor Acceptor ◽  
Insight Into

Density functional study has been performed for a new anticancer agent, cis-[PtCl2(NH3)(2-picoline)] (1), AMD473, now clinically tested. The molecular structure, natural charges, orbital occupancies, vibrational frequencies and metal-ligand stretching force constants were calculated using the modified Perdew-Wang functional (mPW1PW) with the combined D95V(d,p) and LANL2DZ basis set. For comparison, analogous calculations were performed for: cis-[PtCl2(NH3)(3-picoline)] (2), cis-[PtCl2(NH3)(pyridine)] (3) and cisplatin. The interesting structural feature of 1 is almost perpendicular orientation of the 2-picoline ligand with respect to the molecular plane. In the remaining complexes, 2 and 3, the tilt of the pyridine ring is smaller. The position of the methyl group in 1 introduces steric hindrance to an axial approach of the Pt metal. The natural bond analysis (NBO) has provided detailed insight into the electronic donor-acceptor interactions within the platinum coordination sphere. The results clearly indicate that the Pt-N(py) bond is stronger than Pt-NH3 bond, and the Pt-Cl bond trans to 2-picoline is weaker than the cis Pt-Cl bond. Thus, both the trans effect of the 2-picoline ligand and a steric hindrance of Pt in 1 can be of key importance in the different mode of binding of this drug to DNA, in comparison with cisplatin.

Insight into the Reaction Mechanisms of Methanol on PtRu/Pt(111): A Density Functional Study

2016 ◽  
Vol 369 ◽  
pp. 257-266 ◽  
Author(s):  
Qiuyue Ding ◽  
Wenbin Xu ◽  
Pengpeng Sang ◽  
Jing Xu ◽  
Lianming Zhao ◽  
...  
Keyword(s):  
Reaction Mechanisms ◽  
Density Functional ◽  
Functional Study ◽  
Density Functional Study ◽  
Insight Into
Sign in / Sign up

Export Citation Format

Share Document