Vibrational Signature of Charge Solvation vs Salt Bridge Isomers of Sodiated Amino Acids in the Gas Phase

2004 ◽  
Vol 126 (6) ◽  
pp. 1836-1842 ◽  
Author(s):  
Catherine Kapota ◽  
Joël Lemaire ◽  
Philippe Maître ◽  
Gilles Ohanessian
Keyword(s):  
Amino Acids ◽  
Gas Phase ◽  
Salt Bridge ◽  
Charge Solvation

Gas-phase structures of solution-phase zwitterions: Charge solvation or salt bridge?

2009 ◽  
Vol 281 (1-2) ◽  
pp. 97-100 ◽  
Author(s):  
Miriam K. Drayß ◽  
Dirk Blunk ◽  
Jos Oomens ◽  
Nick Polfer ◽  
Carsten Schmuck ◽  
...  
Keyword(s):  
Gas Phase ◽  
Salt Bridge ◽  
Solution Phase ◽  
Phase Structures ◽  
Charge Solvation

scholarly journals Cooperative Salt Bridge Stabilization of Gas-Phase Zwitterions in Neutral Arginine Clusters

2002 ◽  
Vol 106 (1) ◽  
pp. 32-34 ◽  
Author(s):  
Ryan R. Julian ◽  
J. L. Beauchamp ◽  
William A. Goddard
Keyword(s):  
Gas Phase ◽  
Salt Bridge

Kinetic Resolution ofd,l-Amino Acids Based on Gas-Phase Dissociation of Copper(II) Complexes

1999 ◽  
Vol 71 (19) ◽  
pp. 4427-4429 ◽  
Author(s):  
W. Andy Tao ◽  
Duxi Zhang ◽  
Feng Wang ◽  
Peter D. Thomas ◽  
R. Graham Cooks
Keyword(s):  
Amino Acids ◽  
Gas Phase ◽  
Kinetic Resolution ◽  
Gas Phase Dissociation

An On-Line Isocratic HPLC System for the Analysis of PTH-Amino Acids on A Gas-Phase Sequencer

Proteins ◽  
1987 ◽  
pp. 383-394
Author(s):  
J. E. Shively ◽  
D. Hawke ◽  
R. M. Kutny ◽  
B. Krieger ◽  
J. L. Glajch
Keyword(s):  
Amino Acids ◽  
Gas Phase ◽  
Hplc System ◽  
On Line ◽  
Isocratic Hplc

Quantum chemical study on the formation of isopropyl cyanide and its linear isomer in the interstellar medium

2020 ◽  
pp. 1-11
Author(s):  
Keshav Kumar Singh ◽  
Poonam Tandon ◽  
Alka Misra ◽  
Shivani ◽  
Manisha Yadav ◽  
...  
Keyword(s):  
Amino Acids ◽  
Interstellar Medium ◽  
Gas Phase ◽  
Quantum Chemical ◽  
Density Functional ◽  
Quantum Chemical Study ◽  
Chemical Study ◽  
Dark Cloud ◽  
Water Ice ◽  
Hydrocarbon Radicals

Abstract The formation mechanism of linear and isopropyl cyanide (hereafter n-PrCN and i-PrCN, respectively) in the interstellar medium (ISM) has been proposed from the reaction between some previously detected small cyanides/cyanide radicals and hydrocarbons/hydrocarbon radicals. n-PrCN and i-PrCN are nitriles therefore, they can be precursors of amino acids via Strecker synthesis. The chemistry of i-PrCN is especially important since it is the first and only branched molecule in ISM, hence, it could be a precursor of branched amino acids such as leucine, isoleucine, etc. Therefore, both n-PrCN and i-PrCN have significant astrobiological importance. To study the formation of n-PrCN and i-PrCN in ISM, quantum chemical calculations have been performed using density functional theory at the MP2/6-311++G(2d,p)//M062X/6-311+G(2d,p) level. All the proposed reactions have been studied in the gas phase and the interstellar water ice. It is found that reactions of small cyanide with hydrocarbon radicals result in the formation of either large cyanide radicals or ethyl and vinyl cyanide, both of which are very important prebiotic interstellar species. They subsequently react with the radicals CH2 and CH3 to yield n-PrCN and i-PrCN. The proposed reactions are efficient in the hot cores of SgrB2 (N) (where both n-PrCN and i-PrCN were detected) due to either being barrierless or due to the presence of a permeable entrance barrier. However, the formation of n-PrCN and i-PrCN from the ethyl and vinyl cyanide always has an entrance barrier impermeable in the dark cloud; therefore, our proposed pathways are inefficient in the deep regions of molecular clouds. It is also observed that ethyl and vinyl cyanide serve as direct precursors to n-PrCN and i-PrCN and their abundance in ISM is directly related to the abundance of both isomers of propyl cyanide in ISM. In all the cases, reactions in the ice have smaller barriers compared to their gas-phase counterparts.

Sign in / Sign up

Export Citation Format

Share Document