F^19 NMR

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?? ??? ???? ???? ???
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Use the 19 ?? NMR IN Biological Systems
???? ?????????? ????????????????
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Index

• NMR Introduction
• Fluorine Introduction
• AN Overview Of Fluorine NMR
• Applications of ???? ?? NMR
• Reference

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NMR Introduction
NMR in 1946
NMR in recently years
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NMR Introduction

• 1952 Bloch and Purcell
• awarded the Nobel prize for their development
  of a new method for nuclear magnetic precision
  measurements and the subsequent discoveries .
• 1971 Jeener
• The firste two dimentional NMR experiment
  (COSY) .
• 1991 Ernst
• awarded the Nobel prize for his contributions
  to high resolution NMR .
• 2002 Wuthrich
• awarded the Noble prize for his development of
  three-dimensional structure of biological
  macromolecules in solution .
• 2003 Lauterbur and Mansfield
• awarded the Noble prize for their discoveries
  regarding magnetic resonance imaging .

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NMR Introduction

• 1952 Bloch and Purcell
• awarded the Nobel prize for their development
  of a new method for nuclear magnetic precision
  measurements and the subsequent discoveries .
• 1971 Jeener
• The firste two dimentional NMR experiment
  (COSY) .
• 1991 Ernst
• awarded the Nobel prize for his contributions
  to high resolution NMR .
• 2002 Wuthrich
• awarded the Noble prize for his development of
  three-dimensional structure of biological
  macromolecules in solution .
• 2003 Lauterbur and Mansfield
• awarded the Noble prize for their discoveries
  regarding magnetic resonance imaging .

Felix Bloch 1905-1983
Edward M. Purcell 1912-1997
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NMR Introduction

• 1952 Bloch and Purcell
• awarded the Nobel prize for their development
  of a new method for nuclear magnetic precision
  measurements and the subsequent discoveries .
• 1971 Jeener
• The firste two dimentional NMR experiment
  (COSY) .
• 1991 Ernst
• awarded the Nobel prize for his contributions
  to high resolution NMR .
• 2002 Wuthrich
• awarded the Noble prize for his development of
  three-dimensional structure of biological
  macromolecules in solution .
• 2003 Lauterbur and Mansfield
• awarded the Noble prize for their discoveries
  regarding magnetic resonance imaging .

Jean Jeener 1931
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NMR Introduction

• 1952 Bloch and Purcell
• awarded the Nobel prize for their development
  of a new method for nuclear magnetic precision
  measurements and the subsequent discoveries .
• 1971 Jeener
• The firste two dimentional NMR experiment
  (COSY) .
• 1991 Ernst
• awarded the Nobel prize for his contributions
  to high resolution NMR .
• 2002 Wuthrich
• awarded the Noble prize for his development of
  three-dimensional structure of biological
  macromolecules in solution .
• 2003 Lauterbur and Mansfield
• awarded the Noble prize for their discoveries
  regarding magnetic resonance imaging .

Richard R. Ernst 1933
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NMR Introduction

• 1952 Bloch and Purcell
• awarded the Nobel prize for their development
  of a new method for nuclear magnetic precision
  measurements and the subsequent discoveries .
• 1971 Jeener
• The firste two dimentional NMR experiment
  (COSY) .
• 1991 Ernst
• awarded the Nobel prize for his contributions
  to high resolution NMR .
• 2002 John Bennett Fenn
• Nobel Prize for the development of methods for
  identification and structure analyses of
  biological macromolecules
• 2003 Lauterbur and Mansfield
• awarded the Noble prize for their discoveries
  regarding magnetic resonance imaging .

John Bennett Fenn 1917 - 2010
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NMR Introduction

• 1952 Bloch and Purcell
• awarded the Nobel prize for their development
  of a new method for nuclear magnetic precision
  measurements and the subsequent discoveries .
• 1971 Jeener
• The firste two dimentional NMR experiment
  (COSY) .
• 1991 Ernst
• awarded the Nobel prize for his contributions
  to high resolution NMR .
• 2002 Wuthrich
• awarded the Noble prize for his development of
  three-dimensional structure of biological
  macromolecules in solution .
• 2003 Lauterbur and Mansfield
• awarded the Noble prize for their discoveries
  regarding magnetic resonance imaging .

Sir Peter Mansfield
Paul C. Lauterbur
1933
1929 - 2007
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NMR Introduction
Sample Tube
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Fluorine Introduction

• Background

Fluorine is an important element in industrial
chemistry and has applications in a wide range of
industries, such as pharmaceuticals,
agrochemicals, polymers, surfactants and
solvents. It is estimated that more than 20 of
all pharmaceutical compounds contain fluorine.
This includes some of the commercially important
drugs such as Prozac (fluoxetine) and Paxil
(paroxetine).
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GENERAL INTRODUCTION

• ? Why Fluorinated Compounds are Interesting ?
• ? Introduction To Fluorine NMR

The reason that organic chemists are
interested in compounds that contain ?uorine
is simple. Because of ?uorines steric and polar
characteristics, even a single ?uorine
substituent, placed at a propitious position
within a molecule, can have a remarkable effect
upon the physical and chemical properties of
that molecule.
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GENERAL INTRODUCTION
Why Fluorinated Compounds are Interesting

• ? Steric Size
• ? Polar Effects
• ? Effect of Fluorine Substituents on the
• Acidity and Basicity of Compounds
• Analytical Applications in
• Biomedicinal Chemistry
• ? Effect of Fluorinated Substituents
• on the Lipophilicity of Molecules

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GENERAL INTRODUCTION
Why Fluorinated Compounds are Interesting
In terms of its steric impact, ?uorine is
the smallest substituent that can replace a
hydrogen in a molecule, other than an isotope of
hydrogen.

• ? Steric Size
• ? Polar Effects
• ? Effect of Fluorine Substituents on the
• Acidity and Basicity of Compounds
• Analytical Applications in
• Biomedicinal Chemistry
• ? Effect of Fluorinated Substituents
• on the Lipophilicity of Molecules

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GENERAL INTRODUCTION
Why Fluorinated Compounds are Interesting

• ? Steric Size
• ? Polar Effects
• ? Effect of Fluorine Substituents on the
• Acidity and Basicity of Compounds
• Analytical Applications in
• Biomedicinal Chemistry
• ? Effect of Fluorinated Substituents
• on the Lipophilicity of Molecules

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GENERAL INTRODUCTION
Why Fluorinated Compounds are Interesting

• ? Steric Size
• ? Polar Effects
• ? Effect of Fluorine Substituents on the
• Acidity and Basicity of Compounds
• Analytical Applications in
• Biomedicinal Chemistry
• ? Effect of Fluorinated Substituents
• on the Lipophilicity of Molecules

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GENERAL INTRODUCTION
Why Fluorinated Compounds are Interesting

• ? Steric Size
• ? Polar Effects
• ? Effect of Fluorine Substituents on the
• Acidity and Basicity of Compounds
• Analytical Applications in
• Biomedicinal Chemistry
• ? Effect of Fluorinated Substituents
• on the Lipophilicity of Molecules

Over the past decade or so, NMR
spectroscopy has emerged as a screening tool
to facilitate the drug discovery process,
and nowhere has this been more the case
than with 19 ?? NMR spectroscopy .
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GENERAL INTRODUCTION
Why Fluorinated Compounds are Interesting

• ? Steric Size
• ? Polar Effects
• ? Effect of Fluorine Substituents on the
• Acidity and Basicity of Compounds
• Analytical Applications in
• Biomedicinal Chemistry
• ? Effect of Fluorinated Substituents
• on the Lipophilicity of Molecules

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Introduction to Fluorine NMR
Introduction To Fluorine NMR
Isotope Abundance () Spin Relative Sensitivity ?? (MHz) at 1T Shift parameter Range(ppm)
1 ?? 99.98 1 2 1.00 42.57 13
13 ?? 1.108 1 2 0.0159 67.28 250
15 ?? 0.365 1 2 0.00104 4.315 1700
19 ?? 100 1 2 0.834 282.3 900
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Introduction To Fluorine NMR

• Introduction To Fluorine NMR
• ? Interal Reference
• ? Coupling Constants

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Introduction To Fluorine NMR

• Introduction To Fluorine NMR
• ? Interal Reference
• ? Coupling Constants

Fluorotrichloromethane ( ???????? 3 ) has become
the accepted, preferred internal reference
for the measurement of 19 ?? NMR
spectra, and as such, it is assigned a shift of
zero. Other compounds that are commonly
encountered as internal standards, particularly
in the earlier literature, are However,
???????? 3 has the advantage that its
presence will not have any in?uence upon a
compound s chemical shifts, plus its
observed signal lies substantially down?eld of
most signals deriving from carbon-bound ?uorine.
???? 3 ???? 2 ?? - 76.2 ppm
Hexa?uorobenzene - 162.2 ppm
Tri?uoromethylbenzene - 63.2 ppm
Ethyltri?uoroacetate - 75.8 ppm
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Introduction To Fluorine NMR

• Introduction To Fluorine NMR
• ? Chemical Shifts
• ? Coupling Constants

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AN OVERVIEW OF FLUORINE NMR

• Before obtaining and attempting to interpret
  ?uorine NMR spectra, it would be advisable to
  become familiar with some of the fundamental
  concepts related to ?uorine chemical shifts .
• Fluorine Chemical Shifts
• Steric Deshielding of Fluorine
• Solvent Effects on Fluorine Chemical Shifts

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AN OVERVIEW OF FLUORINE NMR

• Fluorine Chemical Shifts
• Steric Deshielding of Fluorine
• Solvent Effects on Fluorine Chemical Shifts

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AN OVERVIEW OF FLUORINE NMR

• Fluorine Chemical Shifts
• Steric Deshielding of Fluorine
• Solvent Effects on Fluorine Chemical Shifts

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AN OVERVIEW OF FLUORINE NMR

• Fluorine Chemical Shifts
• Steric Deshielding of Fluorine
• Solvent Effects on Fluorine Chemical Shifts

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Applications of 19 ?? NMR
Over the past 25 years there have beenumerous
reports of 19 ?? NMR studieso 19 ??
-labeled compounds.
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Applications of ???? ?? NMR

• Fluorine-19 NMR A technique for Metabolism and
  disposition studies
• of fluorinated drugs

Numerous fluorinated drugs are used in
therapeutics. Some of these have been
studied with 19 ?? NMR. This paper describes
the use of this technique for investigating the
metabolism of perfluorinated blood substitutes,
fluorinated anaesthetics and antipsychotics,
and antineoplastic fluoropyrimidines.
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Applications of ???? ?? NMR

• Fluorine-19 NMR A technique for Metabolism and
  disposition studies
• of fluorinated drugs
• ?Why is 19 F suitable for
• biological NMR ?
• ?Application of 19 F NMR
• to invitro studies
• ?Application of 19 F NMR
• to vivo studies

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Applications of ???? ?? NMR

• Fluorine-19 NMR A technique for Metabolism and
  disposition studies
• of fluorinated drugs
• ?Why is ???? ?? suitable for
• biological NMR ?
• ?Application of 19 ?? NMR
• to invitro studies
• ?Application of 19 ?? NMR
• to invivo studies

(1) This naturally-occurring, ubiquitous isotope
has a spin 1 2 and a relative sensitivity of
0.833. Its chemical shift is highly sensitive
to changes in environment and has a wide sweep
range (0-900 ppm), allowing the various
fluorinated compounds to be clearly recognizable.
(2) Simultaneous identification of all the
fluorinated metabolites is possible within the
limits of the sensitivity of the method.
(3) Quantitative detection of the profile of
any fluorinated drug is possible. There is no
confusion with biological components because of
the very low level of fluorine in the organism
(normal plasma concentration 5 x 10 -6 M).
(4) Heterogeneous biological samples, such as
blood, tissues or organs can be directly analysed
with no need for separation, extraction or
derivatization.
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Applications of ???? ?? NMR

• Fluorine-19 NMR A technique for Metabolism and
  disposition studies
• of fluorinated drugs
• ?Why is 19 ?? suitable for
• biological NMR ?
• ?Application of ???? ?? NMR
• to invivo studies
• ?Application of 19 F NMR
• to invitro studies

Fluorinated hydrocarbons and ethers are among
the most commonly used anaesthetic agents.
Wyrwicz et al. have obtained high resolution
19 F NMR spectra of halothane,
methoxyflurane and isoflurane in vivo with a
surface coil centred over the calvarium on a
rabbit head. 19 F NMR demonstrated that
halothane, or a halothane metabolite,
survives in significant amounts in brain tissue
for up to 98 h after anaesthesia.
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Applications of ???? ?? NMR

• Fluorine-19 NMR A technique for Metabolism and
  disposition studies
• of fluorinated drugs
• ?Why is 19 ?? suitable for
• biological NMR ?
• ?Application of 19 F NMR
• to invivo studies
• ?Application of ???? ?? NMR
• to invitro studies
• ?

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Applications of ???? ?? NMR

• Application of 18 ?? In PET/CT

Fludeoxyglucose ( 18 ?? ), also commonly called
fluorodeoxyglucose and abbreviated 18 ??
FDG, 18 ?? -FDG or FDG, is a
radiopharmaceutical used in the medical imaging
modality positron emission tomography (PET/CT).
Chemically, it is 2-deoxy-2-( 18 ??
)fluoro-D-glucose, a glucose analog, with the
positron-emitting radioactive isotope fluorine-18
substituted for the normal hydroxyl group at the
2' position in the glucose molecule.
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Applications of ???? ?? NMR

• Application of 18 ?? In PET/CT

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PET
CT
PET/CT
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Applications of ???? ?? NMR
FLUORINE CHEMICAL SHIFT CHANGES IN BIOLOGICAL
SYSTEMS
One of the most useful properties of the 19 ??
nucleus is the high sensitivity of the ?uorine
shielding parameter to changes in the local
environment. This makes ?uorine an ideal
candidate for monitoring functional important
transitions in biological systems via NMR
spectroscopic methods.
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Applications of ???? ?? NMR

• Fluorine NMR as an Analytical Tool

The potency of fluorine NMR as an analytical
technique is demonstrated by observations made
with the drug 5-fluorouracil. This material is a
widely-used anti-cancer drug. Significant side
effects of the drug have been noted, including
cardiotoxicity. It was thought that the side
effects could be the result of impurities in the
drug that arise during its manufacture or during
storage. Figure shows the fluorine NMR spectrum
of a sample of the drug in common use before
1994. The presence of many fluorine-containing
compounds at trace levels is indicated by the
spectrum. Subsequent identification of some of
these led to improved procedures for storage and
use of the drug.
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Applications of ???? ?? NMR

• Structural and functional study of
• F-labeled nucleic acids

Nishimoto and colleagues prepared a series of
F-labeled oligodeoxynucleotides with
5-fluouridine (5-FU) as the 19 ?? NMR
reporter, and successfully monitored the
struro-20-deoxyctural changes of DNA from single
strand to triplex at di?erent temperatures by
19 ?? NMR.
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Applications of ???? ?? NMR
Drug screening and discovery by ???? ??
labeling
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Applications of ???? ?? NMR
Drug screening and discovery by ???? ??
labeling
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REFERENCES

• 1. Chambers, R. D. Fluorine in Organic
  Chemistry John Wiley Sons New York , 1973
  .
• 2. Welch , J. T. Eswarakrishnan , S. Fluorine
  in Bioorganic Chemistry John Wiley Sons
  New York , 1991 , 261 p.
• 3. Gombler , W. Schaebs , J. Willner , H.
  Inorg. Chem. 1990 , 29 , 26972698 .
• 4. Brey , W. S. Brey , M. L. In
  Encyclopedia of Nuclear Magnetic Resonance
  Grant , D. M. , Harris , R. K. ,
  Eds. John Wiley and Sons Chichester , 1996
  Vol. 3 , 20632071 .
• 5. Lambert , J. B. Mazzola , E. P.
  Nuclear Magnetic Resonance Spectroscopy
  Pearson Education, Inc. Upper Saddle
  River , 2004 , 341 p.
• 6. Berkowitz , D. B. Karukurichi , K. R.
  de la Salud - Bea , R. Nelson , D. L.
  McCune , C. D. J. Fluorine Chem.
  2008, 129, 731 742 .
• 7. Weigert , F. J. J. Fluorine Chem. 1990
  ,46 ,375384 .
• 8. Burton , D. J. Hartgraves, G. A. J.
  Fluorine Chem. 2007, 128, 11981215 .
• 9. DeMarco , R. A. Fox , W. B. Moniz , W.
  B. Sojka , S. A. J. Magn. Res. 1975, 18,
  522526 .
• 10. Santini, G. Le Blanc, M. Riess, J.
  G. J. Fluorine Chem. 1977, 10, 363373 .

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Thanks For Your Attention
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