Cryo-bioorganic chemistry: Freezing effect on stereoselection of L- and DL-leucine cooligomerization in aqueous solution

T. Vajda, M. Hollósi

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

The chirality of L-/DL-leucine (50-50%) cooligomerization was investigated in liquid and frozen aqueous solutions. Cooligomerization was carried out by carbonyldiimidazole activation without initiator at an ambient (+ 22 °C) and frozen (- 18 °C) temperature, respectively. The separated samples obtained after different time intervals of treatment were completely hydrolyzed (HC1) and the diastereomeric L- and D-leucine derivates of Marfey's reagent (1-fluoro-2,4-dinitrophenyl-5-L-alanine amide) were then traced and evaluated by RP-HPLC analysis. After 9 days of oligomerization, the L-Leu content was slightly enhanced in the liquid (57%) and somewhat more enhanced in the frozen (64%) samples. After 17 days, however, the L-Leu content had decreased in the liquid (53%) and frozen (56%) conditions. These L-enantiomer amplifications indicate that an L-antipode is preferentially incorporated into the α-helical turn of the oligomer in the earlier stage of cooligomerization, while, later, the D-antipode is also incorporated. The role of ice in the improved stereoselection is discussed. This is the first recorded example of the effect of freezing on stereoselection.

Original languageEnglish
Pages (from-to)343-346
Number of pages4
JournalCellular and Molecular Life Sciences
Volume58
Issue number2
Publication statusPublished - 2001

Fingerprint

Freezing
Leucine
Ice
Liquids
Amides
Alanine
Oligomerization
Enantiomers
Chirality
High Pressure Liquid Chromatography
Oligomers
Temperature
Amplification
Chemical activation
Marfey's reagent

Keywords

  • Cooligomerization
  • Enantiomeric excess
  • Freezing
  • Prebiotic chiral amplification
  • Stereoselection

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Cell Biology

Cite this

@article{c8b7b0c74ce34bd286e83519fe9b27bd,
title = "Cryo-bioorganic chemistry: Freezing effect on stereoselection of L- and DL-leucine cooligomerization in aqueous solution",
abstract = "The chirality of L-/DL-leucine (50-50{\%}) cooligomerization was investigated in liquid and frozen aqueous solutions. Cooligomerization was carried out by carbonyldiimidazole activation without initiator at an ambient (+ 22 °C) and frozen (- 18 °C) temperature, respectively. The separated samples obtained after different time intervals of treatment were completely hydrolyzed (HC1) and the diastereomeric L- and D-leucine derivates of Marfey's reagent (1-fluoro-2,4-dinitrophenyl-5-L-alanine amide) were then traced and evaluated by RP-HPLC analysis. After 9 days of oligomerization, the L-Leu content was slightly enhanced in the liquid (57{\%}) and somewhat more enhanced in the frozen (64{\%}) samples. After 17 days, however, the L-Leu content had decreased in the liquid (53{\%}) and frozen (56{\%}) conditions. These L-enantiomer amplifications indicate that an L-antipode is preferentially incorporated into the α-helical turn of the oligomer in the earlier stage of cooligomerization, while, later, the D-antipode is also incorporated. The role of ice in the improved stereoselection is discussed. This is the first recorded example of the effect of freezing on stereoselection.",
keywords = "Cooligomerization, Enantiomeric excess, Freezing, Prebiotic chiral amplification, Stereoselection",
author = "T. Vajda and M. Holl{\'o}si",
year = "2001",
language = "English",
volume = "58",
pages = "343--346",
journal = "Cellular and Molecular Life Sciences",
issn = "1420-682X",
publisher = "Birkhauser Verlag Basel",
number = "2",

}

TY - JOUR

T1 - Cryo-bioorganic chemistry

T2 - Freezing effect on stereoselection of L- and DL-leucine cooligomerization in aqueous solution

AU - Vajda, T.

AU - Hollósi, M.

PY - 2001

Y1 - 2001

N2 - The chirality of L-/DL-leucine (50-50%) cooligomerization was investigated in liquid and frozen aqueous solutions. Cooligomerization was carried out by carbonyldiimidazole activation without initiator at an ambient (+ 22 °C) and frozen (- 18 °C) temperature, respectively. The separated samples obtained after different time intervals of treatment were completely hydrolyzed (HC1) and the diastereomeric L- and D-leucine derivates of Marfey's reagent (1-fluoro-2,4-dinitrophenyl-5-L-alanine amide) were then traced and evaluated by RP-HPLC analysis. After 9 days of oligomerization, the L-Leu content was slightly enhanced in the liquid (57%) and somewhat more enhanced in the frozen (64%) samples. After 17 days, however, the L-Leu content had decreased in the liquid (53%) and frozen (56%) conditions. These L-enantiomer amplifications indicate that an L-antipode is preferentially incorporated into the α-helical turn of the oligomer in the earlier stage of cooligomerization, while, later, the D-antipode is also incorporated. The role of ice in the improved stereoselection is discussed. This is the first recorded example of the effect of freezing on stereoselection.

AB - The chirality of L-/DL-leucine (50-50%) cooligomerization was investigated in liquid and frozen aqueous solutions. Cooligomerization was carried out by carbonyldiimidazole activation without initiator at an ambient (+ 22 °C) and frozen (- 18 °C) temperature, respectively. The separated samples obtained after different time intervals of treatment were completely hydrolyzed (HC1) and the diastereomeric L- and D-leucine derivates of Marfey's reagent (1-fluoro-2,4-dinitrophenyl-5-L-alanine amide) were then traced and evaluated by RP-HPLC analysis. After 9 days of oligomerization, the L-Leu content was slightly enhanced in the liquid (57%) and somewhat more enhanced in the frozen (64%) samples. After 17 days, however, the L-Leu content had decreased in the liquid (53%) and frozen (56%) conditions. These L-enantiomer amplifications indicate that an L-antipode is preferentially incorporated into the α-helical turn of the oligomer in the earlier stage of cooligomerization, while, later, the D-antipode is also incorporated. The role of ice in the improved stereoselection is discussed. This is the first recorded example of the effect of freezing on stereoselection.

KW - Cooligomerization

KW - Enantiomeric excess

KW - Freezing

KW - Prebiotic chiral amplification

KW - Stereoselection

UR - http://www.scopus.com/inward/record.url?scp=0035106678&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0035106678&partnerID=8YFLogxK

M3 - Article

C2 - 11289315

AN - SCOPUS:0035106678

VL - 58

SP - 343

EP - 346

JO - Cellular and Molecular Life Sciences

JF - Cellular and Molecular Life Sciences

SN - 1420-682X

IS - 2

ER -