PMID- 21726870
OWN - NLM
STAT- MEDLINE
DCOM- 20111021
LR  - 20121115
IS  - 1873-3778 (Electronic)
IS  - 0021-9673 (Linking)
VI  - 1218
IP  - 31
DP  - 2011 Aug 5
TI  - Computational modeling of capillary electrophoretic behavior of primary amines 
      using dual system of 18-crown-6 and beta-cyclodextrin.
PG  - 5344-51
LID - 10.1016/j.chroma.2011.06.030 [doi]
AB  - Using capillary electrophoresis (CE) three chiral primary amine compounds 
      1-aminoindan (AI), 1-(1-naphthyl)ethylamine (NEA) and 
      1,2,3,4-tetrahydro-1-naphthylamine (THAN), exhibited only partial or no 
      separation when beta-cyclodextrin (betaCD) was used as chiral selector. The use of 
      18-crown-6 (18C6) as a second additive with betaCD resulted in an enhanced 
      separation. A molecular modeling study, using molecular mechanics and the 
      semiempirical PM6 calculations, was used to help explaining the mechanism of the 
      enantiodifferentiation and to predict the separation process. Optimization of the 
      structures of the complexes by the PM6 method indicate that the poor separation 
      obtained in the presence of the betaCD chiral selector alone is due to the small 
      binding energy differences (DeltaDeltaE) of 4.7, 1.1 and 1.2 kcal mol(-1) for AI, NEA and 
      THAN, respectively. In the presence of 18C6 it was suggested that a sandwich 
      compound between 18C6, amine and betaCD is formed. Theoretical calculations show 
      that a significant increase in the binding energy is obtained for the sandwich 
      compounds indicating strong hydrophobic and van der Waals interactions that show 
      enhanced enantiodifferentiation.
CI  - Copyright (c) 2011 Elsevier B.V. All rights reserved.
FAU - Elbashir, Abdalla A
AU  - Elbashir AA
AD  - Department of Chemistry, College of Science, Sultan Qaboos University, Box 36, 
      Al-Khod 123, Oman. hajaae@yahoo.com
FAU - Suliman, FakhrEldin O
AU  - Suliman FO
LA  - eng
PT  - Journal Article
DEP - 20110617
PL  - Netherlands
TA  - J Chromatogr A
JT  - Journal of chromatography. A
JID - 9318488
RN  - 0 (Amines)
RN  - 0 (Crown Ethers)
RN  - 0 (beta-Cyclodextrins)
RN  - 63J177NC5B (18-crown-6)
SB  - IM
MH  - Amines/chemistry/*isolation & purification
MH  - Computer Simulation
MH  - Crown Ethers/*chemistry
MH  - Electrophoresis, Capillary/*instrumentation/methods
MH  - Models, Chemical
MH  - Stereoisomerism
MH  - beta-Cyclodextrins/*chemistry
EDAT- 2011/07/06 06:00
MHDA- 2011/10/22 06:00
CRDT- 2011/07/06 06:00
PHST- 2011/02/05 00:00 [received]
PHST- 2011/06/02 00:00 [revised]
PHST- 2011/06/07 00:00 [accepted]
PHST- 2011/07/06 06:00 [entrez]
PHST- 2011/07/06 06:00 [pubmed]
PHST- 2011/10/22 06:00 [medline]
AID - S0021-9673(11)00842-9 [pii]
AID - 10.1016/j.chroma.2011.06.030 [doi]
PST - ppublish
SO  - J Chromatogr A. 2011 Aug 5;1218(31):5344-51. doi: 10.1016/j.chroma.2011.06.030. 
      Epub 2011 Jun 17.