Active oxygen; basic concept and applications

1. A Review of Active Oxygen ; Basic concept and
Applications to Industrial, Environmental,
Pharmaceutical, and Medical Fields
活性酸素の基礎と工業、環境、医療分野への応用
By Isamu Katsuyama

2. Topics (トピックス）
A. Generation and Physiological Action of
Active Oxygen Species in an Organism
生体内の活性酸素種の生成と生理作用
B. Practical Applications of Active Oxygen
Species and Their Future
活性酸素種の応用実例とその将来性
C. Physicochemical Aspects of Molecular
Oxygen and Active Oxygen Species
酸素および活性酸素種の物理化学

3. D. Method for the Generation of Singlet
Oxygen
一重項酸素の発生法
E. Method for the Detection of Singlet
Oxygen
一重項酸素の検出・測定法
F. Example for Successful Application of
Singlet Oxygen
一重項酸素の応用へ成功例

4. A. Generation and Physiological Action of Active
Oxygen Species in an Organism
生体内の活性酸素種の生成と生理作用
O2 O2
-
, H2O2, HO.
, 1
O2 H2O
Active Oxygen Species
Antioxidant
Cyto-toxicity
Application for Biochemical Reactions
and Defense Systems against Other
Organisms
e-
Food Generation of Energy
excess amount

5. Example of Application of Active Oxygen
Species for Biochemical Reactions
活性酸素種の生化学反応の例
1. Biosynthesis of Prostaglandines (PGs)
プロスタグランジン類の生合成
2. Biosynthesis of Thyroid Hormones
甲状線ホルモンの生合成

6. 1. Biosynthesis of Prostaglandines (PGs)
プロスタグランジン類 (PGs) の生合成
COOH
OOH
O
O
COOH
COOH
OH
O
O
COOH
OH
O
HO
Arachidonic Acid
PGG2
prostaglandin syntase
O2
PGH2
PGE2

7. 2. Biosynthesis of Thyroid Hormones (T4)
甲状線ホルモン (T4) の生合成
OH
I I
COO-
O-
O
I I
COO-
O
O
H
HO
O
I I
O
COOR
O
I I
O
O-
OC
O-
OH
DHPPA 1 2 3
DHPPA
O2
O2
O
I I
O
HOOC
O
O
I I
O
HOOC
O
OHO
COOH
H2N
OH
II
I
I
Thyroxine (T4)
DIT DIT
T4
COOH
NH2
OH
II
DIT
4 5
H2O2
V. B. Oza et al., J. Am. Chem. Soc. 1997, 119, 11315.

8. Example of Application of Active Oxygen Species
for Defense System against Other Organisms
活性酸素種の生体防御の例
1. Disinfection in the Mouth（口腔内殺菌）
2. Disinfection in Leukocyto（白血球による殺菌）
In summary, active oxygen species are
necessarily generated in an organism, and
have important roles in biochemical reactions
and defense systems against other organisms.

9. B. Practical Applications of Active Oxygen
Species and Their Future
活性酸素種の応用例とその将来性
1. Application for Medical Treatment
（病気治療への応用）
2. Development of New Functional Materials
(新規機能性物質の開発）
3. Application for Environmental
Purification (環境浄化への応用）

10. 1. Application for Medical Treatment
A) Treatment of Cancer (癌治療）
• Anticancer Drugs (抗癌剤）
• Photodynamic Therapy, PDT
(光力学療法）
B) Treatment of Bacterium Diseases (細菌病治療）
C) Treatment of Virus Diseases (ウイルス病治療）

11. Anticancer Drug
• Some anticancer drugs can generate active
oxygen species, mainly, the hydroxy radical,
which is known to cause DNA strand breaks.
O
O
OH
OHMeO O
OH
X
O
sugar
Example
Anthracyclines

12. Characteristics of This Type of
Anticancer Drug (AD)
i. This type of AD has a high activity in the tissues
because the hydroxy radical is the most toxic
species.
ii. In general, AD tends to be retained not only in
tumor tissues but also in normal tissues.
This type of AD often leads to a high toxicity in normal tissue.
Improvement of the selectivity should be necessary.

13. Photodynamic Therapy, PDT
Abstract
i. PDT is a treatment modality using a
photosensitising drug and light to kill
cells.
ii. The clinical use of PDT requires the
presence of a photosensitizing agent,
oxygen, and light of a specific wavelength.

14. Mechanism of Tumor Destruction Using PDT
Photosensitizer
Activated Photosensitizer
1O2
Cytototoxic Oxyproducts
Cellular Destruction
Light
3O2
Substrate
1O2
3O2

15. The Appeal of PDT in Oncology
i. Singlet oxygen has both a short lifetime
and a short radius of action.
ii. Photosentisitizer tends to be retained in
tumor tissues for a longer period of time
as compared with normal tissues.
These potentials can lead to minimal toxicity in normal tissue.

16. Clinical Applications of PDT
• PDT has been clinically tested in a
variety of tumors including intra-
peritoneal, gastrointestinal,
genitourinary, pulmonary, head,
neck and skin cancers.

17. Major Problems in PDT
i. Limited depth of tissue penetration and
exited skin phototoxicity due to the
limitation of older photosensitizers
ii. PDT has a limited application due to
its mechanism.

18. Examples of Photosensitizers
First Generation of Photosensitizers
NH N
HNN
CO2H
OH
OH
HO2C
Haematoporphyrin and its derivatives

19. Second Generation of Photosensitizers
NH
N
N
N N
HNN
N
Phtalocyanine and its derivatives

20. Conclusion of PDT
• Development of newer photosensitizers is
in progress in order to solve the problems.
• According to such improvement and the
potential for minimal toxicity in normal
tissue, PDT will become an important part
of cancer treatment.

21. Future Directions of Cancer Treatment
• Although PDT has a limited application, it
can be used with other therapies such as
anticancer drug.
• Studies on combining PDT with the other
therapeutic modalities are in their initial
phases, and will improve outcome and
minimize toxicity of cancer treatment.

22. 2. Development of New Functional Materials
1
O2
XR
H
OO
O O
O
HO
XR
A
B
C
En
[2+2]
[4+2]
Singlet oxygen is a useful reagent for the synthesis
of oxygen-containing materials, which are
sometimes reported to have interesting properties.

23. The product, ergosterol-5,8-endoperoxide is reported to
be selectively toxic to some bacteria and viruses.
Ｐｌａｎｔａ Med., 1999, 65, 732.; Pharmazie, 1989, 44, 579; Ｐｌａｎｔａ Med., 1989,
55, 389.
HO
HO2
R
HO
H
R
1
O2
Preparation of Ergosterol-5,8-endoperoxide from
Ergosterol and Singlet Oxygen
Example 1

24. The product, 1,2-dioxetanes are widely used in
numerous applications including gene
expression studies, DNA sequencing, and the
identification of infectious agents.
SR1
OX
SR1
OX
OO OR2
OX
OO
1
O2 R2
OH
Lewis Acid
Synthesis of 1,2-Dioxetanes from Vinyl Sulfide and Singlet Oxygen
H. A. Tafti et al., J. Am. Chem. Soc., 1997, 119, 245.
Example 2

25. 3. Application for Environmental
Purification
a. Photodegradation of Polymer 高分子の分解
b. Photodegradation of Harmful Materials
有害物質の分解
ex) Endocrine Disruptors (Environmental
Hormone)
c. Disinfection of Water and Foods
水や食品の消毒

26. a. Photodegradation of Polymer
Example
• Singlet oxygen has been reported to cause
photoinduced oxidative decomposition of the
electro-luminescent material, BCHA-PPV.
R. D. Scurlock et al., J. Am. Chem. Soc. 1995, 117, 10194.

27. • The degradation is postulated to proceed via addition of
singlet oxygen to the double bond in the macromolecule.
OH
OH
HO
HO
OH
OH
HO
HO
O
O
1
O2
OH
OH
HO
HO
O
H
H
O
BCHA-PPV

28. C. Physicochemical Aspects of Molecular Oxygen
and Active Oxygen Species
酸素および活性酸素種の物理化学
この他にROOH, ROO., RO., HOX
(X=Cl, Br, I)

29. Electron Configuration of Mol. Oxygen
1s
2s
2p
1s
2s
2p
1s*
1s
2s
2s
2p
2p
2p
2p
Parallel Electron Spin (Triplet)
Atomic O Molecular O2 Atomic O
biradical

30. Electron Configuration of Singlet
Oxygen and Superoxide
2s
2s
2p
2p
2p
2s
2s
2p
2p
2p
Singlet Oxygen Superoxide
Anti-parallel
Electron
Spin (Singlet)
1
O2
O2
mono radicalanion

31. Physical Properties of Mol. Oxygen, Singlet
Oxygen, and Superoxide
Singlet Oxygen
22.5
1.2155
96
45min(vacum)
Next Table(in Solv.)
Superoxide
-9.9
1.28(KO2)
88.8
5-10min(CH3CN)
1hour(DMF)
Mol. Oxygen
0
1.2074
117.9
R. Energy (kcal/mol)
Distance between two
atoms (A)
Bond Dissociation E.
(kcal/mol)
Life time

32. Life Time of Singlet Oxygen in Various Solvents
Solvent
H2O
D2O
CH3OH
CD3OD
CH3COCH3
CD3COCD3
Solvent
CH3CN
CD3CN
CHCl3
CDCl3
CH2Cl2
CF3Cl
Lifetime/s
3.3
68.0
5-11.4
224
46.5
690
Lifetime/s
54.4
600
60
640
105
1,000

33. D. Method for the Generation of Singlet Oxygen
一重項酸素の発生法
1. Photosensitising Oxidation （光増感酸化）
2. Hydrogen Peroxide and Hypochlorite
（過酸化水素と次亜塩素酸塩）
3. Heat of Organic and Inorganic Peroxides
（有機及び無機過酸化物の加熱）
4. Heat of Phosphine Ozonides
（ホスフィンオゾニドの加熱）
5. Hydrogen Peroxide and Molybdenum Salt
（過酸化水素とモリブデン塩）

34. E. Method for the Detection and Measurement of
Singlet Oxygen
一重項酸素の検出・測定法
Luminescent Analysis (発光分析)
1. Use of Chemical Luminous Reagents
化学発光試薬の使用
2. Detection of Luminescence of Singlet Oxygen
一重項酸素の発光の検出
• The Luminescent at Visible Light Region
可視光域での発光
• The Luminescent at Near-IR Region
近赤外域での発光

35. • Near-IR region includes almost no emission
arising from other species.
Prof. Suzuki et al. have recently developed two kinds
of ultra-high sensitivity instruments (TIA and CIA).
The near-IR luminescence spectroscopy is
the most reliable method for the detection
and measurement of singlet oxygen.

36. F. Example for Successful Application of
Singlet Oxygen
一重項酸素の応用への成功例
1. Deactivation of WSS Virus on Eggs Using
Singlet Oxygen
一重項酸素による卵付着WSSウィルスの不活化
2. Degradation of Endocrine Disruptors
(Environmental Hormone) Using Singlet Oxygen
一重項酸素による内分泌かく乱物質（環境ホルモン）の分解

37. Examples of Endocrine Disruptors
(Environmental Hormone) Degradation Using
Singlet Oxygen
1
O2
Clm Cln
PCB
H
C
CCl3
DDT
C
CH3
CH3
OHHO
Cl Cl
Bisphenol A
HO C9H19
Nonylphenol
Degradation