U.S. patent application number 09/849163 was filed with the patent office on 2002-11-07 for azo compounds for type i phototherapy.
This patent application is currently assigned to MALLINCKRODT INC.. Invention is credited to Achilefu, Samuel I., Bugaj, Joseph E., Cantrell, Gary L., Dorshow, Richard B., Rajagopalan, Raghavan.
Application Number | 20020164287 09/849163 |
Document ID | / |
Family ID | 25305212 |
Filed Date | 2002-11-07 |
United States Patent
Application |
20020164287 |
Kind Code |
A1 |
Rajagopalan, Raghavan ; et
al. |
November 7, 2002 |
AZO COMPOUNDS FOR TYPE I PHOTOTHERAPY
Abstract
Novel azo compounds and their bioconjugates for phototherapy
and/or photodiagnosis of tumors and other lesions. The azo
derivatives of the present invention are designed to absorb at the
low-energy ultraviolet, visible, or near-infrared (NIR) region of
the electromagnetic spectrum. The phototherapeutic effect is caused
by direct interaction of free radicals, the reactive intermediate
produced upon photoexcitation of the azo compound, with the tissue
of interest.
Inventors: |
Rajagopalan, Raghavan;
(Maryland Heights, MO) ; Cantrell, Gary L.; (Troy,
IL) ; Bugaj, Joseph E.; (St. Charles, MO) ;
Achilefu, Samuel I.; (St. Louis, MO) ; Dorshow,
Richard B.; (St. Louis, MO) |
Correspondence
Address: |
Beverly A. Lyman
Wood, Herron & Evans, L.L.P.
2700 Carew Tower
441 Vine Street
Cincinnati
OH
45202-2917
US
|
Assignee: |
MALLINCKRODT INC.
675 McDonnell Boulevard
St. Louis
MO
|
Family ID: |
25305212 |
Appl. No.: |
09/849163 |
Filed: |
May 4, 2001 |
Current U.S.
Class: |
424/9.6 ;
424/178.1; 530/391.1; 536/55; 544/234 |
Current CPC
Class: |
A61P 13/08 20180101;
A61K 49/0056 20130101; A61P 9/00 20180101; A61K 49/0026 20130101;
A61K 49/0039 20130101; A61P 9/10 20180101; A61P 15/14 20180101;
C07D 471/06 20130101; A61K 41/0057 20130101; A61K 47/64 20170801;
A61K 49/0041 20130101; A61P 43/00 20180101; A61P 25/28 20180101;
A61P 35/00 20180101 |
Class at
Publication: |
424/9.6 ;
424/178.1; 536/55; 530/391.1; 544/234 |
International
Class: |
A61K 049/00; C08B
037/00; A61K 039/395 |
Claims
What is claimed is:
1. A compound of formula 6wherein Q is a single bond or
--CR.sup.1R.sup.2; R.sup.1 and R.sup.2 are independently selected
from the group consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl,
C1-C10 alkoxyalkyl, C1-C10 polyhydroxyalkyl,
--(CH.sub.2).sub.aCO.sub.2H, and --(CH.sub.2).sub.bNR.sup.3R.sup.4;
R.sup.3 and R.sup.4 are independently selected from the group
consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, C1-C10
polyhydroxyalkyl, and --(CH.sub.2).sub.aCO.sub.2H; R.sup.5,
R.sup.6, and R.sup.7 are independently selected from the group
consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, hydroxyl,
--SO.sub.3H, C1-C10 alkoxyl, C1-C10 polyhydroxyalkyl, C1-C10
polyalkoxyalkyl, --(CH.sub.2).sub.aCO.sub.2H, and
--(CH.sub.2).sub.bNR.sup.3R.sup.4; X is selected from the group
consisting of --CR.sup.8R.sup.9, --O--, --NR.sup.3, --S--, and
--C.dbd.O; Y is selected from the group consisting of
--CR.sup.10R.sup.11, --O--, --NR.sup.3, --S--, and --C.dbd.O; Z is
selected from the group consisting of --CR.sup.12R.sup.13, --O--,
--NR.sup.3, --S--, and --C.dbd.O; R.sup.8 to R.sup.13 are
independently selected from the group consisting of hydrogen,
C1-C10 alkyl, C5-C10 aryl, C1-C10 alkoxyalkyl, C1-C10
polyhydroxyalkyl, --(CH.sub.2).sub.aCO.sub.2H, and
--(CH.sub.2).sub.bNR.sup.3R.sup.4; R.sup.5-R.sup.6,
R.sup.6-R.sup.7, R.sup.8-R.sup.10, or R.sup.10-R.sup.12 together
optionally form a six-membered ring; E is either a hydrogen atom or
is selected from the group comprising antibodies, peptides,
peptidomimetics, carbohydrates, glycomimetics, drugs, hormones, or
nucleic acids; L is a linker unit selected from the group
comprising --(CH.sub.2).sub.c--, --(CH.sub.2).sub.dCONR.sup.3--,
--N(R.sup.3)CO(CH.sub.2).sub.d--, --OCO(CH.sub.2).sub.e--,
--(CH.sub.2).sub.fCO.sub.2--, --OCONH--, --OCO.sub.2--, --HNCONH--,
--HNCSNH--, --HNNHCO--, --OSO.sub.2--,
--NR.sup.3(CH.sub.2).sub.gCONR.sup- .4--,
--CONR.sup.3(CH.sub.2).sub.hNR.sup.4CO--, and
--NR.sup.3CO(CH.sub.2).sub.iCONR.sup.4; and a to i independently
range from 0 to 10.
2. The compound of claim 1, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--C.dbd.O; Y is --CR.sup.10R.sup.11; Z is --CR.sup.12R.sup.13;
R.sup.10 to R.sup.13 are independently selected from the group
consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules,
heat-sensitive bacterioendotoxin (ST) receptor binding molecules,
neurotensin receptor binding molecules, bombesin receptor binding
molecules, cholecystekinen (CCK) receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d--, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup.4; and a to i independently
range from 0 to 6.
3. The compound of claim 1, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is --C.dbd.O; Z is selected from the group
consisting of --CR.sup.12R.sup.13, --O--, and --NR.sup.3; R.sup.8,
R.sup.9, R.sup.12 and R.sup.13 are independently selected from the
group consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d--, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup.4; and a to i independently
range from 0 to 6.
4. The compound of claim 1, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is selected from the group consisting of
--CR.sup.10R.sup.11, --O--, and --NR.sup.3; Z is --C.dbd.O; R.sup.8
to R.sup.11 are independently selected from the group consisting of
hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup- .4; and a to i
independently range from to 6.
5. The compound of claim 1, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is --CR.sup.10OR.sup.11; Z is
--CR.sup.12R.sup.13; R.sup.8 and R.sup.10 together form a benzene
ring; R.sup.9 and R.sup.11 are radicals that form carbon-carbon
bond; R.sup.12 and R.sup.13 are independently selected from the
group consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup- .4; and a to i
independently range from 0 to 6.
6. The compound of claim 1, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is --CR.sup.10R.sup.11; Z is --O--; R.sup.8
and R.sup.10 together form a benzene ring; R.sup.9 and R.sup.11 are
radicals that form carbon-carbon bond, R.sup.12 and R.sup.13 are
independently selected from the group consisting of hydrogen,
C1-C10 alkyl, C5-C10 aryl, and --(CH.sub.2).sub.aCO.sub.2H; E is
selected from the group consisting of somatostatin receptor binding
molecules, ST receptor binding molecules, neurotensin receptor
binding molecules, bombesin receptor binding molecules, CCK
receptor binding molecule, steroid receptor binding molecules, and
carbohydrate receptor binding molecules; L is a linker unit
selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup- .4; and a to i
independently range from 0 to 6.
7. The compound of claim 1, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is --CR.sup.10R.sup.11; Z is --NR.sup.3;
R.sup.8 and R.sup.10 together form a benzene ring; R.sup.9 and
R.sup.11 are radicals that form carbon-carbon bond; R.sup.12 and
R.sup.13 are independently selected from the group consisting of
hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup- .4; and a to i
independently range from 0 to 6.
8. The compound of claim 1, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is --CR.sup.10R.sup.11; Z is --C.dbd.O;
R.sup.8 and R.sup.10 together form a benzene ring; R.sup.9 and
R.sup.11 are radicals that form carbon-carbon bond; R.sup.12 and
R.sup.13 are independently selected from the group consisting of
hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, and
--(CH.sub.2).sub.dCONR.sup.3--, NR.sup.3CO(CH.sub.2).sub.iCONR.sup-
.4; and a to i independently range from 0 to 6.
9. A method of performing a phototherapeutic or photodiagnostic
procedure comprising: administering an effective amount of the
compound of formula 1 7 wherein Q is a single bond or
--CR.sup.1R.sup.2; R.sup.1 and R.sup.2 are independently selected
from the group consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl,
C1-C10 alkoxyalkyl, C1-C10 polyhydroxyalkyl,
--(CH.sub.2).sub.aCO.sub.2H, and --(CH.sub.2).sub.bNR.sup.3R.sup.4;
R.sup.3 and R.sup.4 are independently selected from the group
consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, C1-C10
polyhydroxyalkyl, and --(CH.sub.2).sub.aCO.sub.2H; R.sup.5,
R.sup.6, and R.sup.7 are independently selected from the group
consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, hydroxyl,
--SO.sub.3H, C1-C10 alkoxyl, C1-C10 polyhydroxyalkyl, C1-C10
polyalkoxyalkyl, --(CH.sub.2).sub.aCO.sub.2H, and
--(CH.sub.2).sub.bNR.sup.3R.sup.4; X is selected from the group
consisting of --CR.sup.8R.sup.9, --O--, --NR.sup.3, --S--, and
--C.dbd.O; Y is selected from the group consisting of
--CR.sup.10R.sup.11, --O--, --NR.sup.3, --S--, and --C.dbd.O; Z is
selected from the group consisting of --CR.sup.12R.sup.13, --O--,
--NR.sup.3, --S--, and --C.dbd.O; R.sup.8 to R.sup.13 are
independently selected from the group consisting of hydrogen,
C1-C10 alkyl, C5-C10 aryl, C1-C10 alkoxyalkyl, C1-C10
polyhydroxyalkyl, --(CH.sub.2).sub.aCO.sub.2H, and
--(CH.sub.2).sub.bNR.sup.3R.sup.4; R.sup.5-R.sup.6,
R.sup.6-R.sup.7, R.sup.8-R.sup.10, or R.sup.10-R.sup.12 together
optionally form a six-membered ring; E is either a hydrogen atom or
is selected from the group comprising antibodies, peptides,
peptidomimetics, carbohydrates, glycomimetics, drugs, hormones, or
nucleic acids; L is a linker unit selected from the group
comprising --(CH.sub.2).sub.c--, --(CH.sub.2).sub.dCONR.sup.3--,
--N(R.sup.3)CO(CH.sub.2).sub.d--, --OCO(CH.sub.2).sub.e--,
--(CH.sub.2).sub.fCO.sub.2--, --OCONH--, --OCO.sub.2--, --HNCONH--,
--HNCSNH--, --HNNHCO--, --OSO.sub.2--,
--NR.sup.3(CH.sub.2).sub.gCONR.sup.4--,
--CONR.sup.3(CH.sub.2).sub.hNR.su- p.4CO--, and
--NR.sup.3CO(CH.sub.2).sub.iCONR.sup.4; and a to i independently
range from 0 to 10; photoactivating the compound; and performing a
phototherapeutic or photodiagnostic procedure.
10. The method of claim 9, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--C.dbd.O; Y is --CR.sup.10R.sup.11; Z is --CR.sup.12R.sup.13;
R.sup.10 to R.sup.13 are independently selected from the group
consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules,
heat-senstiive bacterioendotoxin (ST) receptor binding molecules,
neurotensin receptor binding molecules, bombesin receptor binding
molecules, cholecystekinen (CCK) receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d--, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup.4; and a to i independently
range from 0 to 6.
11. The method of claim 9, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is --C.dbd.O; Z is selected from the group
consisting of --CR.sup.12R.sup.13, --O--, and --NR.sup.3; R.sup.8,
R.sup.9, R.sup.12 and R.sup.13 are independently selected from the
group consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d--, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup.4; and a to i independently
range from 0 to 6.
12. The method of claim 9, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is selected from the group consisting of
--CR.sup.10R.sup.11, --O--, and --NR.sup.3; Z is --C.dbd.O; R.sup.8
to R.sup.11 are independently selected from the group consisting of
hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup- .4; and a to i
independently range from 0 to 6.
13. The method of claim 9, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is --CR.sup.10R.sup.11; Z is
--CR.sup.12R.sup.13; R.sup.8 and R.sup.10 together form a benzene
ring; R.sup.9 and R.sup.11 are radicals that form carbon-carbon
bond; R.sup.12 and R.sup.13 are independently selected from the
group consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup- .4; and a to i
independently range from 0 to 6.
14. The method of claim 9, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is --CR.sup.10R.sup.11; Z is --O--; R.sup.8
and R.sup.10 together form a benzene ring, R.sup.9 and R.sup.11 are
radicals that form carbon-carbon bond; R.sup.12 and R.sup.13 are
independently selected from the group consisting of hydrogen,
C1-C10 alkyl, C5-C10 aryl, and --(CH.sub.2).sub.aCO.sub.2H; E is
selected from the group consisting of somatostatin receptor binding
molecules, ST receptor binding molecules, neurotensin receptor
binding molecules, bombesin receptor binding molecules, CCK
receptor binding molecule, steroid receptor binding molecules, and
carbohydrate receptor binding molecules; L is a linker unit
selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup- .4; and a to i
independently range from 0 to 6.
15. The method of claim 9, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is --CR.sup.10R.sup.11; Z is --NR.sup.3;
R.sup.8 and R.sup.10 together form a benzene ring; R.sup.9 and
R.sup.11 are radicals that form carbon-carbon bond; R.sup.12 and
R.sup.13 are independently selected from the group consisting of
hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup- .4; and a to i
independently range from 0 to 6.
16. The method of claim 9, wherein Q is --CR.sup.1R.sup.2; R.sup.1
and R.sup.2 are independently selected from the group consisting of
hydrogen and C1-C10 alkyl; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
hydroxyl, --SO.sub.3H, and --(CH.sub.2).sub.aCO.sub.2H; X is
--CR.sup.8R.sup.9; Y is --CR.sup.10R.sup.11; Z is --C.dbd.O;
R.sup.8 and R.sup.10 together form a benzene ring; R.sup.9 and
R.sup.11 are radicals that form carbon-carbon bond, and R.sup.12
and R.sup.13 are independently selected from the group consisting
of hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup- .4; and a to i
independently range from 0 to 6.
Description
FIELD OF THE INVENTION
[0001] This invention relates generally to novel azo bioconjugates
for use in phototherapy.
BACKGROUND OF THE INVENTION
[0002] The use of visible and near-infrared (NIR) light in clinical
practice is growing rapidly. Compounds absorbing or emitting in the
visible, NIR, or long-wavelength (UV-A, >350 nm) region of the
electromagnetic spectrum are potentially useful for optical
tomographic imaging, endoscopic visualization, and phototherapy.
However, a major advantage of biomedical optics lies in its
therapeutic potential. Phototherapy has been demonstrated to be a
safe and effective procedure for the treatment of various surface
lesions, both external and internal. Its efficacy is comparable to
that of radiotherapy, but without the harmful radiotoxicity of
critical non-target organs.
[0003] Phototherapy has been in existence for many centuries and
has been used to treat various skin surface ailments. As early as
1400 B.C. in India, plant extracts (psoralens), in combination with
sunlight, were used to treat vitiligo. In 1903, Von Tappeiner and
Jesionek used eosin as a photosensitizer for the treatment of skin
cancer, lupus of the skin, and condylomata of female genitalia.
Over the years, the combination of psoralens and ultraviolet A
(low-energy) radiation has been used to treat a wide variety of
dermatological diseases including psoriasis, parapsoriasis,
cutaneous T-cell lymphoma, eczema, vitiligo, areata, and neonatal
bilirubinemia. Although the potential of cancer phototherapy has
been recognized since early 1900's, systematic studies to
demonstrate safety and efficacy began only in 1967 with the
treatment of breast carcinoma. Dougherty et al. subsequently
conclusively established that long-term cure is possible with
photodynamic therapy (PDT). Currently, phototherapeutic methods are
also being investigated for the treatment of some cardiovascular
disorders such as atherosclerosis and vascular restenosis for the
treatment rheumatoid arthritis, and for the treatment of some
inflammatory diseases such as Crohn's disease.
[0004] Phototherapeutic procedures require photosensitizers (i.e.
chromophores) which have high absorptivity. These compounds should
preferably be chemically inert, and become activated only upon
irradiation with light of an appropriate wavelength.
Light-initiated selective tissue injury can be induced when these
photosensitizers bind to target tissues, either directly or through
attachment to a bioactive carrier. Furthermore, if the
photosensitizer is also a chemotherapeutic agent (e.g.
anthracycline antitumor agents), then an enhanced therapeutic
effect can be attained.
[0005] Effective phototherapeutic agents should have the following
properties: (a) large molar extinction coefficient; (b) long
triplet lifetime; (c) high yield of singlet oxygen and/or other
reactive intermediates, viz., free radicals, nitrenes, carbenes,
open-shell ionic species such as cabonium ions and the like; (d)
efficient energy or electron transfer to cellular components; (e)
low tendency to form aggregation in aqueous milieu; (f) efficient
and selective targeting of lesions; (g) rapid clearance from blood
and non-target tissues; (h) low systemic toxicity; and (i) lack of
mutagenicity.
[0006] Photosensitizers operate via two distinct pathways, termed
Types 1 and 2. The type 1 mechanism is shown in the following
scheme: 1
[0007] After photoexcitation, the Type 1 mechanism involves direct
energy or electron transfer from the photosensitizer to the
cellular components, thereby causing cell death. After
photoexcitation, the Type 2 mechanism involves distinct steps as
shown in the following scheme: 2
[0008] In the first step, singlet oxygen is generated by energy
transfer from the triplet excited state of the photosensitizer to
the oxygen molecules surrounding the tissues. In the second step,
collision of a singlet oxygen with the tissues promotes tissue
damage. In both Type 1 and Type 2 mechanisms, the photoreaction
proceeds via the lowest triplet state of the sensitizer. Hence, a
relatively long triplet lifetime is required for effective
phototherapy. In contrast, a relatively short triplet lifetime is
required to avoid photodamage to the tissue caused by
photosensitizers.
[0009] The biological basis of tissue injury brought about by tumor
phototherapeutic agents has been the subject of intensive study.
Various reasonable biochemical mechanisms for tissue damage have
been postulated even though the type and number of photosensitizers
employed in these studies are relatively small. These biochemical
mechanisms are as follows: a) cancer cells upregulate the
expression of low density lipoprotein (LDL) receptors, and PDT
agents bind to LDL and albumin selectively; (b) porphyrin-like
substances are selectively taken up by proliferative
neovasculature; (c) tumors often contain an increased number of
lipid bodies and are thus able to bind to hydrophobic
photosensitizers; (d) a combination of "leaky" tumor vasculature
and reduced lymphatic drainage causes porphyrin accumulation; (e)
tumor cells may have increased capabilities for phagocytosis or
pinocytosis of porphyrin aggregates; (f) tumor associated
macrophages may be largely responsible for the concentration of
photosensitizers in tumors; and (g) cancer cells may undergo
apoptosis induced by photosensitizers. Among these mechanisms, (f)
and (g) are the most general and, of these two alternatives, there
is a general consensus that (f) is the most likely mechanism by
which the phototherapeutic effect of porphyrin-like compounds is
induced.
[0010] Most of the currently known photosensitizers are commonly
referred to as PDT agents and operate via the Type 2 mechanism. For
example, Photofrin II, a hematoporphyrin derivative, was approved
by the United States Food and Drug Administration for the treatment
of bladder, esophageal, and late-stage lung cancers. However,
Photofrin II has been shown to have several drawbacks: low molar
absorptivity, (.epsilon.=3000M.sup.-1), low singlet oxygen quantum
yield (.phi.=0.1), chemical heterogeneity, aggregation, and
prolonged cutaneous photosensitivity. Hence, there has been
considerable effort in developing safer and more effective
photosensitizers for PDT that exhibit improved light absorbance
properties, better clearance, and decreased skin photosensitivity
compared to those of Photofrin II. These photosensitizers include
monomeric porphyrin derivatives, corrins, cyanines,
phthalocyanines, phenothiazines, rhodamines, hypocrellins, and the
like. However, these phototherapeutic agents also mainly operate
via the Type 2 mechanism.
[0011] Surprisingly, there has not been much attention directed at
developing Type 1 phototherapeutic agents, despite the fact that
the Type 1 mechanism seems inherently more efficient than the Type
2 mechanism. First, unlike Type 2, Type 1 photosensitizers do not
require oxygen for causing cellular injury. Second, the Type 1
mechanism involves two steps (photoexcitation and direct energy
transfer) whereas the Type 2 mechanism involves three steps
(photoexcitation, singlet oxygen generation, and energy transfer).
Furthermore, some tumors have hypoxic regions that render the Type
2 mechanism ineffective. In spite of the drawbacks associated with
the Type 2 mechanism, however, only a small number of compounds
have been developed that operate through the Type I mechanism, e.g.
anthracyline antitumor agents.
[0012] Thus, there is a need to develop effective phototherapeutic
agents that operate through the Type 1 mechanism. Phototherapeutic
efficacy can be further enhanced if the excited state
photosensitizers can generate reactive intermediates such as free
radicals, nitrenes, carbenes, and the like. These have much longer
lifetimes than the excited chromophore and have been shown to cause
considerable cell injury.
SUMMARY OF THE INVENTION
[0013] The present invention addresses this need and discloses
novel azo derivatives and their bioconjugates that absorb in the
low-energy, ultraviolet, visible, or near-infrared (NIR) region of
the electromagnetic spectrum that are used for the phototherapy of
tumors and other lesions. More specifically, the present invention
discloses azo compounds having the formula 1 3
[0014] where Q is a single bond or --CR.sup.1R.sup.2; R.sup.1 and
R.sup.2 are independently selected from the group consisting of
hydrogen, C1-C10 alkyl, C5-C10 aryl, C1-C10 alkoxyalkyl; C1-C10
polyhydroxyalkyl, --(CH.sub.2).sub.aCO.sub.2H, and
--(CH.sub.2).sub.bNR.sup.3R.sup.4; R.sup.3 and R.sup.4 are
independently selected from the group consisting of hydrogen,
C1-C10 alkyl, C5-C10 aryl, C1-C10 polyhydroxyalkyl, and
--(CH.sub.2).sub.aCO.sub.2H; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
C1-C10 alkyl, C5-C10 aryl, hydroxyl, --SO.sub.3H, C1-C10 alkoxyl,
C1-C10 polyhydroxyalkyl, C1-C10 polyalkoxyalkyl,
--(CH.sub.2).sub.aCO.sub.2H, and --(CH.sub.2).sub.bNR.sup.3R.sup.4;
X is selected from the group consisting of --CR.sup.8R.sup.9,
--O--, --NR.sup.3, --S--, and --C.dbd.O; Y is selected from the
group consisting of --CR.sup.10R.sup.11, --O--, --NR.sup.3, --S--,
and --C.dbd.O; Z is selected from the group consisting of
--CR.sup.12R.sup.13, --O--, --NR.sup.3, --S--, and --C.dbd.O;
R.sup.8 to R.sup.13 are independently selected from the group
consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, C1-C10
alkoxyalkyl, C1-C10 polyhydroxyalkyl, --(CH.sub.2).sub.aCO.sub.2H,
and --(CH.sub.2).sub.bNR.sup.3R.sup.4; R.sup.5-R.sup.6,
R.sup.6-R.sup.7, R.sup.8-R.sup.10, or R.sup.10-R.sup.12 together
optionally form a six-membered alicyclic or aromatic ring; E is
either a hydrogen atom or is selected from the group consisting of
antibodies, peptides, peptidomimetics, carbohydrates,
glycomimetics, drugs, hormones, or nucleic acids; L is a linker
unit selected from the group consisting of --(CH.sub.2).sub.c--,
--(CH.sub.2).sub.dCONR.sup.3--, --N(R.sup.3)CO(CH.sub.2).sub.d--,
--OCO(CH.sub.2).sub.e--, --(CH.sub.2).sub.fCO.sub.2--, --OCONH--,
--OCO.sub.2--, --HNCONH--, --HNCSNH--, --HNNHCO--, --OSO.sub.2--,
--NR.sup.3(CH.sub.2).sub.gCONR.sup- .4--,
--CONR.sup.3(CH.sub.2).sub.hNR.sup.4CO--, and
--NR.sup.3CO(CH.sub.2).sub.iCONR.sup.4; and a to i independently
range from 0 to 10.
[0015] The present invention also discloses a method of performing
a phototherapeutic or photodiagnostic procedure using the inventive
azo compounds and their derivatives. In the method, an effective
amount of an azo photosensitizer having the formula 1 4
[0016] is administered to a subject; where Q is a single bond or
--CR.sup.1R.sup.2; R.sup.1 and R.sup.2 are independently selected
from the group consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl,
C1-C10 alkoxyalkyl, C1-C10 polyhydroxyalkyl,
--(CH.sub.2).sub.aCO.sub.2H, and --(CH.sub.2).sub.bNR.sup.3R.sup.4;
R.sup.3 and R.sup.4 are independently selected from the group
consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, C1-C10
polyhydroxyalkyl, and --(CH.sub.2).sub.aCO.sub.2H; R.sup.5,
R.sup.6, and R.sup.7 are independently selected from the group
consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, hydroxyl,
--SO.sub.3H, C1-C10 alkoxyl, C1-C10 polyhydroxyalkyl, C1-C10
polyalkoxyalkyl, --(CH.sub.2).sub.aCO.sub.2H, and
--(CH.sub.2).sub.bNR.sup.3R.sup.4; X is selected from the group
consisting of --CR.sup.8R.sup.9, --O--, --NR.sup.3, --S--, and
--C.dbd.O; Y is selected from the group consisting of
--CR.sup.10R.sup.11, --O--, --NR.sup.3, --S--, and --C.dbd.O; Z is
selected from the group consisting of --CR.sup.12R.sup.13, --O--,
--NR.sup.3, --S--, and --C.dbd.O; R.sup.8 to R.sup.13 are
independently selected from the group consisting of hydrogen,
C1-C10 alkyl, C5-C10 aryl, C1-C10 alkoxyalkyl, C1-C10
polyhydroxyalkyl, --(CH.sub.2).sub.aCO.sub.2H, and
--(CH.sub.2).sub.bNR.sup.3R.sup.4; R.sup.5-R.sup.6,
R.sup.6-R.sup.7, R.sup.8-R.sup.10, or R.sup.10-R.sup.12 together
optionally form a six-membered ring; E is either a hydrogen atom or
is selected from the group consisting of antibodies, peptides,
peptidomimetics, carbohydrates, glycomimetics, drugs, hormones, or
nucleic acids; L is a linker unit selected from the group
consisting of --(CH.sub.2).sub.c--, --(CH.sub.2).sub.dCONR.sup.3--,
--N(R.sup.3)CO(CH.sub.2).sub.d--, --OCO(CH.sub.2).sub.e--,
--(CH.sub.2).sub.fCO.sub.2--, --OCONH--, --OCO.sub.2--, --HNCONH--,
--HNCSNH--, --HNNHCO--, --OSO.sub.2--,
--NR.sup.3(CH.sub.2).sub.gCONR.sup- .4--,
--CONR.sup.3(CH.sub.2).sub.hNR.sup.4CO--, and
--NR.sup.3CO(CH.sub.2).sub.iCONR.sup.4; and a to i independently
range from 0 to 10. The compound is photoactivated and a
phototherapeutic or photodiagnostic procedure for tumors, impaired
vasculature or other lesions is subsequently performed.
[0017] For targeting purposes, external attachment of an eptiope is
used unless the azo compounds themselves preferentially accumulate
in the target tissue. For example, if the photosensitizing
chromophore is an anthracycline moiety, it can bind to cancer cells
directly and may not require an epitope for targeting purposes.
[0018] These and other advantages and embodiments of the inventive
compounds and methods will be apparent in view of the following
figures, description, and example.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a schematic pathway for activation of the
inventive compounds.
[0020] FIG. 2 is a schematic pathway for the synthesis of a cyclic
azoxanthene derivative.
[0021] FIG. 3 is a schematic pathway for the synthesis of an
azoacridine derivative.
[0022] FIG. 4 is a schematic pathway for the synthesis of an
azocoumarin derivative.
DETAILED DESCRIPTION OF THE INVENTION
[0023] The present invention discloses novel azo derivatives and
their bioconjugates for phototherapy of tumors and other
lesions.
[0024] Accordingly, the present invention provides new and
structurally diverse compositions comprising organic azo compounds
of the general formula 1 5
[0025] wherein Q is a single bond or --CR.sup.1R.sup.2; R.sup.1 and
R.sup.2 are independently selected from the group consisting of
hydrogen, C1-C10 alkyl, C5-C10 aryl, C1-C10 alkoxyalkyl, C1-C10
polyhydroxyalkyl, --(CH.sub.2).sub.aCO.sub.2H, and
--(CH.sub.2).sub.bNR.sup.3R.sup.4; R.sup.3 and R.sup.4 are
independently selected from the group consisting of hydrogen,
C1-C10 alkyl, C5-C10 aryl, C1-C10 polyhydroxyalkyl, and
--(CH.sub.2).sub.aCO.sub.2H; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
C1-C10 alkyl, C5-C10 aryl, hydroxyl, --SO.sub.3H, C1-C10 alkoxyl,
C1-C10 polyhydroxyalkyl, C1-C10 polyalkoxyalkyl,
--(CH.sub.2).sub.aCO.sub.2H, and --(CH.sub.2).sub.bNR.sup.3R.sup.4;
X is selected from the group consisting of --CR.sup.8R.sup.9,
--O--, --NR.sup.3, --S--, and --C.dbd.O; Y is selected from the
group consisting of --CR.sup.10R.sup.11, --O--, --NR.sup.3, --S--,
and --C.dbd.O; Z is selected from the group consisting of
--CR.sup.12R.sup.13, --O--, --NR.sup.3, --S--, and --C.dbd.O;
R.sup.8 to R.sup.13 are independently selected from the group
consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, C1-C10
alkoxyalkyl, C1-C10 polyhydroxyalkyl, --(CH.sub.2).sub.aCO.sub.2H,
and --(CH.sub.2).sub.bNR.sup.3R.sup.4; R.sup.5-R.sup.6,
R.sup.6-R.sup.7, R.sup.8-R.sup.10, or R.sup.10-R.sup.12 together
optionally form a six-membered ring; E is either a hydrogen atom or
is selected from the group comprising antibodies, peptides,
peptidomimetics, carbohydrates, glycomimetics, drugs, hormones, or
nucleic acids; L is a linker unit selected from the group
comprising --(CH.sub.2).sub.c--, --(CH.sub.2).sub.dCONR.sup.3--,
--N(R.sup.3)CO(CH.sub.2).sub.d--, --OCO(CH.sub.2).sub.e--,
--(CH.sub.2).sub.fCO.sub.2--, --OCONH--, --OCO.sub.2--, --HNCONH--,
--HNCSNH--, --HNNHCO--, --OSO.sub.2--,
--NR.sup.3(CH.sub.2).sub.gCONR.sup.4--,
--CONR.sup.3(CH.sub.2).sub.hNR.su- p.4CO--, and
--NR.sup.3CO(CH.sub.2).sub.iCONR.sup.4; and a to i independently
range from 0 to 10.
[0026] In one embodiment, azo compounds according to the present
invention have the general formula 1 wherein Q is
--CR.sup.1R.sup.2; R.sup.1 and R.sup.2 are independently selected
from the group consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl,
and --(CH.sub.2).sub.aCO.sub.2H; R.sup.5, R.sup.6, and R.sup.7 are
independently selected from the group consisting of hydrogen,
C1-C10 alkyl, hydroxyl, --SO.sub.3H, C1-C10 alkoxyl, and
--(CH.sub.2).sub.aCO.sub.2H; X is selected from the group
consisting of --CR.sup.8R.sup.9, --O--, --NR.sup.3, and --C.dbd.O;
Y is selected from the group consisting of --CR.sup.10R.sup.11,
--O--, --NR.sup.3, and --C.dbd.O; Z is selected from the group
consisting of --CR.sup.12R.sup.13, --O--, --NR.sup.3, and
--C.dbd.O; R.sup.8 to R.sup.13 are independently selected from the
group consisting of hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; R.sup.8 and R.sup.10 together
optionally form a six-membered ring; E is selected from the group
consisting of somatostatin receptor binding molecules,
heat-sensitive bacterioendotoxin (ST) receptor binding molecules,
neurotensin receptor binding molecules, bombesin receptor binding
molecules, cholecystekinen (CCK) receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--(CH.sub.2).sub.dCONR.sup.3--, --N(R.sup.3)CO(CH.sub.2).sub.d--,
--HNCONH--, --HNCSNH--, and --NR.sup.3CO(CH.sub.2).sub.iCONR.sup.4;
and a to i independently range from 0 to 6.
[0027] In another embodiment, azo compounds according to the
invention having the general formula 1 above wherein Q is
--CR.sup.1R.sup.2; R.sup.1 and R.sup.2 are independently selected
from the group consisting of hydrogen and C1-C10 alkyl; R.sup.5,
R.sup.6, and R.sup.7 are independently selected from the group
consisting of hydrogen, hydroxyl, --SO.sub.3H, and
--(CH.sub.2).sub.aCO.sub.2H; X is selected from the group
consisting of --CR.sup.8R.sup.9 and --C.dbd.O; Y is selected from
the group consisting of --CR.sup.10R.sup.11, --NR.sup.3, and
--C.dbd.O; Z is selected from the group consisting of
--CR.sup.12R.sup.13, --O--, --NR.sup.3, and --C.dbd.O; R.sup.8 to
R.sup.13 are independently selected from the group consisting of
hydrogen, C1-C10 alkyl, C5-C10 aryl, and
--(CH.sub.2).sub.aCO.sub.2H; R.sup.8 and R.sup.10 together
optionally form a six-membered ring; E is selected from the group
consisting of somatostatin receptor binding molecules, ST receptor
binding molecules, neurotensin receptor binding molecules, bombesin
receptor binding molecules, CCK receptor binding molecule, steroid
receptor binding molecules, and carbohydrate receptor binding
molecules; L is a linker unit selected from the group consisting of
--N(R.sup.3)CO(CH.sub.2).sub.d- --, --(CH.sub.2).sub.dCONR.sup.3--,
and NR.sup.3CO(CH.sub.2).sub.iCONR.sup- .4; and a to i
independently range from 0 to 6.
[0028] The inventive compounds operate through the Type 1 mechanism
as shown in FIG. 1 wherein --N.dbd.N-- is the azo moiety that
undergoes nitrogen extrusion upon photoactivation, thereby
producing free radicals. Ar is an aromatic chromophore that
undergoes photosensitization. Aliphatic azo compounds can also be
used for phototherapy, but may require high-energy light for
activation. L is the linker between the chromophore and the
epitope. Epitope (E) is a particular region of the molecule that is
recognized by and binds to the target surface. An epitope is
usually, but not always, associated with biomolecules. Biomolecules
include hormones, amino acids, peptides, peptidomimetics, proteins,
nucleosides, nucleotides, nucleic acids, enzymes, carbohydrates,
glycomimetics, lipids, albumins, mono- and polyclonal antibodies,
receptors, inclusion compounds such as cyclodextrins, and receptor
binding molecules. Specific examples of biomolecules include
steroid hormones for the treatment of breast and prostate lesions;
somatostatin, bombesin, CCK, and neurotensin receptor binding
molecules for the treatment of neuroendocrine tumors; CCK receptor
binding molecules for the treatment of lung cancer; ST receptor and
carcinoembryonic antigen (CEA) binding molecules for the treatment
of colorectal cancer; dihyroxyindolecarboxylic acid and other
melanin producing biosynthetic intermediates for the treatment of
melanoma; integrin receptor and atherosclerotic plaque binding
molecules for the treatment of vascular diseases; and amyloid
plaque binding molecules for the treatment of brain lesions.
Examples of synthetic polymers include polyaminoacids, polyols,
polyamines, polyacids, oligonucleotides, aborols, dendrimers, and
aptamers.
[0029] Coupling of a photodiagnostic and/or phototherapeutic agent
to biomolecules can be accomplished by methods well known in the
art, as disclosed in Hnatowich et al., Radiolabeling of Antibodies:
A simple and efficient method, Science, 1983, 220, p. 613; Pelegrin
et al., Photoimmunodiagnostics with antibody-fluorescein
conjugates: in vitro and in vivo preclinical studies, Journal of
Cellular Pharmacology, 1992, 3, pp. 141-145; and U.S. Pat. No.
5,714,342, each of which is expressly incorporated by reference
herein in its entirety. Successful specific targeting of
fluorescent dyes to tumors using antibodies and peptides for
diagnostic imaging of tumors has been demonstrated by us and others
as described in Achilefu et al., Novel receptor-targeted
fluorescent contrast agents for in vivo imaging of tumors,
Investigative Radiology, 2000, 35, pp. 479-485; Ballou et al.,
Tumor labeling in vivo using cyanine conjugated monoclonol
antibodies, Cancer Immunology and Immunotherapy, 1995, 41, pp.
257-263; and Licha et al., New contrast agent for optical imaging:
acid cleavable conjugates of cyanine dyes with biomolecules, in
Biomedical Imaging: Reporters, Dyes and Instrumentation,
Proceedings of SPIE, 1999, 3600, pp. 29-35, each of which is
expressly incorporated by reference herein in its entirety.
Therefore, receptor-targeted phototherapeutic agents of the present
invention should be effective in the treatment of various
lesions.
[0030] In the process outlined in FIG. 1, photoexcitation of the
aromatic chromophore effects rapid intramolecular energy transfer
to the azo group, resulting in N--C bond rupture with concomitant
extrusion of molecular nitrogen and formation of diradicals. The
diradicals can also combine with each other to form neutral
molecules, provided that their spatial orientation is optimal. The
nitrogen that is released could be in a vibrationally excited state
and may cause additional cellular injury. This process is very
similar to the process observed with azides. For targeting
purposes, an external attachment of an epitope is usually required
unless the azo compounds themselves preferentially accumulate in
the target tissue, thereby obviating the need for an additional
binding group. For example, if the Ar moiety is an anthracycline
moiety, it can bind to cancer cells directly and may not require an
epitope for targeting purposes.
[0031] The synthesis of azo compounds is accomplished by a variety
of methods well known in the art, as disclosed in Sandler and Karo,
Azo Compounds, Organic Functional Group Preparations, 1986,
Academic Press: New York, pp. 353-409, which is expressly
incorporated by reference herein in its entirety. The azo
derivatives of the invention contain additional functionalities
that can be used to attach various types of biomolecules, synthetic
polymers, and organized aggregates for selective delivery to
various organs or tissues of interest. Preparations of
representative compounds from the embodiments are shown in FIGS.
2-4.
[0032] FIG. 2 shows a typical preparation of a cyclic azoxanthene
derivative 5. Methyl 2-chloro-5-nitrobenzoate 1 is reacted with
3-hydroxybenzyl alcohol 2 and thereafter saponified and cyclized to
the nitroxanthone 3. The xanthone 3 is then converted to the azo
precursor 4 in four standard steps. The hydrazino derivative 4 is
then oxidized with either mercuric oxide or lead tetraacetate and
then conjugated to any desired biomolecule of interest using
bifunctional coupling reagents such as phosgene, thiophosgene,
carbonyldiimidazole, disuccinimidyl carbonate, and the like.
Specifically, the biomolecule of the invention pertains to those
binding to colorectal, cervical, ovarian, lung, and neuroendocrine
tumors. These include somatostatin, cholesystekinin (CCK),
bombesin, neuroendrocrine, and heat sensitive bacterioendotoxin
(ST) receptor binding compounds.
[0033] With reference to FIG. 3, the azoacridine derivative 9 can
be prepared in a similar manner to the cyclic azoxanthene
derivative whose synthetic scheme is shown in FIG. 2. Methyl
2-chloro-5-nitrobenzoate 1 is reacted with 3-hydroxybenzyl amine 6
and thereafter saponified and cyclized to the nitroacridone 7. The
acridone 7 is then converted to the azo precursor 8 in four
standard steps. The hydrazino derivative 8 is then oxidized with
either mercuric oxide or lead tetraacetate and then conjugated to a
biomolecule, as previously described, using bifunctional coupling
reagents such as disuccinimidyl carbonate, disuccinimidyl oxalate,
phosgene, thiophosgene, carbonyldiimidazole and the like.
[0034] With reference to FIG. 4, a typical preparation of an
azocoumarin derivative 12 is shown. The phenol 10 is first
alkylated with methyl bromoacetate and then transformed to the azo
compound 11 by standard methods. The ester 11 is saponified and
conjugated to the biomolecule using the known bifunctional coupling
reagents previously described, or can be conjugated directly using
automated peptide synthesis methods as is known to one of skill in
the art.
[0035] The novel compositions of the present invention may vary
widely depending on the contemplated application. For tumors, the
biomolecule is selected from the class of tumor markers including,
but not limited to, somatostatin, bombesin, neurotensin, CCK, ST,
estrogen, and progesterone receptor binding compounds. For vascular
lesions, the biomolecule may be selected from the class of
integrins, selecting, vascular endothelial growth factor, fibrins,
tissue plasminogen activator, thrombin, low density lipoprotein
(LDL), high density lipoprotein (HDL), Sialyl Lewis.sup.X and its
mimics, and atherosclerotic plaque binding compounds.
[0036] As previously described, some compounds accumulate in tumors
or other lesions without the assistance of a bioactive carrier.
Administration of delta-aminolevulinic acid, an intermediate in
porphyrin biosynthesis, results in a two-fold uptake of porphyrins
in tumors compared to normal tissues. Similarly, administration of
dihydroxyindole-2-carboxylic acid, an intermediate in melanin
biosynthesis, produces substantially enhanced levels of melanin in
melanoma cells compared to normal cells. Thus, a photosensitizer
may be delivered to the site of lesion by attaching it to these
types of biosynthetic intermediates.
[0037] Methods of performing therapeutic procedures with
compositions of the invention are also disclosed. The method
encompasses administering to a patient an effective amount of the
compositions of the invention contained in a pharmaceutically
acceptable formulation. Thereafter, the photosensitizer is allowed
to accumulate in the region of interest, followed by illumination
with light of wavelength 300 to 1200 nm, preferably 350 to 850 nm,
at the site of the lesion. If the lesion is on the skin surface, it
can be directly illuminated; otherwise, endoscopic catheters
equipped with a light source may be employed to achieve a
phototherapeutic effect. The intensity, power, duration of
illumination, and the wavelength of the light may vary widely
depending on the location and site of the lesions. The fluence rate
is preferably, but not always, kept below 200 mW/cm.sup.2 to
minimize thermal effects. Appropriate power depends on the size,
depth, and pathology of the lesion. The inventive compositions have
broad clinical utility which includes, but is not limited to,
phototherapy of tumors, inflammatory processes, and impaired
vasculature.
[0038] The inventive compositions can be formulated into
photodiagnostic or phototherapeutic compositions for enteral (oral
or rectal), parenteral, topical, or cutaneous administration.
Topical or cutaneous delivery of the photosensitizer may also
include aerosols, creams, gels, solutions, etc. The compositions
are administered in doses effective to achieve the desired
diagnostic or therapeutic objective. Such doses may vary widely
depending upon the particular complex employed, the organs or
tissues to be examined, the equipment employed in the clinical
procedure, the efficacy of the treatment achieved, and the like.
These compositions contain an effective amount of the
phototherapeutic agent along with conventional pharmaceutical
carriers and excipients appropriate for the type of administration
contemplated. These compositions may also include stabilizing
agents and skin penetration enhancing agents and also may contain
pharmaceutically acceptable buffers, emulsifiers, surfactants, and,
optionally, electrolytes such as sodium chloride.
[0039] Formulations for enteral administration may vary widely as
is well known in the art. In general, such formulations are
liquids, which include an effective amount of the composition in an
aqueous solution or suspension. Such enteral compositions may
optionally include buffers, surfactants, emulsifiers, thixotropic
agents, and the like. Compositions for oral administration may also
contain flavoring agents and other ingredients for enhancing their
organoleptic qualities. A topical application can be formulated as
a liquid solution, water/oil emulsion, or suspension of particles,
depending on the particular nature of the agent and the type of
tissue to be targeted. If the azo compound is water soluble, for
instance, a solution in water may be applied to or into the target
tissue. The delivery of the azo compounds into and through the skin
may be enhanced by using well known methods and agents such as
transdermal permeation enhancers, for example, "azone",
N-alkylcyclic amides, dimethylsulfoxide, long-chained aliphatic
acids (C10), etc. If the azo compound is not water soluble, it may
be dissolved in a biocompatible oil (soybean oil, fish oil, vitamin
E, linseed oil, vegetable oil, glyceride esters, long-chained fatty
esters, etc.) and emulsified with surface-active compounds
(vegetable or animal phospholipids; lecithin; long-chained fatty
salts and alcohols; Pluronics: polyethylene glycol esters and
ethers; etc.) in water to make a topical cream, suspension,
water/oil emulsion, water/oil microemulsion, or liposomal
suspension to be delivered or applied to the target region. In the
case of liposomes, the azo compound may be attached to or be
contained in the lamellar material.
[0040] The dose of the photosensitizer may vary from about 0.1
mg/kg body weight to about 500 mg/kg body weight. In one
embodiment, the dose is in the range of about 0.5 to 2 mg/kg body
weight. As one example, for compositions administered parenterally,
a sterile aqueous solution or suspension of the photosensitizer may
be present in a concentration ranging from about 1 nM to about 0.5
M, typically in a concentration from about 1 .mu.M to about 10
mM.
[0041] In general, a formulated azo compound is administered at a
dose or in a concentration which is effective, upon exposure to
light, to partially or completely inactivate a target tissue within
a biological medium. The biological medium is exposed for a period
of time to light of a wavelength that is effective to activate the
dye which produces type I destruction in the target tissue. The
concentration of the azo compound at the target tissue is the
outcome of either passive or active uptake processes in the tissue.
An example of passive uptake would be where the azo compound is
attached or is contained within a particulate carrier. If the
carrier is of an appropriate size, in the range of about 100 nm to
about 1000 nm, it will "leak" into the perfusion boundary of
vascular tumors. An example of active uptake would be where a
receptor based attachment binds a particular receptor that is
expressed on the target tissue. The effective concentration of the
azo compound is thus dependent on the nature of the formulation,
method of delivery, target tissue, activation method and toxicity
of the azo to the surrounding normal tissue.
[0042] The following example illustrates a specific embodiment of
the invention pertaining to the preparation and properties of a
typical bioconjugate derived from bombesin, a bioactive peptide,
and a phototherapeutic molecule, the azocoumarin derivative 11b as
shown in FIG. 4.
EXAMPLE
Synthesis of Azocoumarin-bombesin (7-14) Conjugate
[0043] The peptide is prepared by fluorenylmethoxycarbonyl (Fmoc)
solid phase peptide synthesis strategy with a commercial peptide
synthesizer from Applied Biosystems (Model 432A SYNERGY Peptide
Synthesizer). The first peptide cartridge containes Wang resin
pre-loaded with an amide resin on 25-.mu.mole scale. The amino acid
cartridges are placed on the peptide synthesizer and the product is
synthesized from the C- to the N-terminal position.
[0044] Coupling of the Fmoc-protected amino acids (75 .mu.mol) to
the resin-bound free terminal amine (25 .mu.mol) is carried out
with 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium
hexafluorophosphate (HBTU, 75 .mu.mol)/N-hydroxybenzotriazole
(HOBt, 75 .mu.mol). Each Fmoc protecting group on the solid support
is removed with 20% piperidine in dimethylformamide before a
subsequent amino acid is coupled to it. The last cartridge contains
the azo compound 11b as shown in FIG. 4, which is coupled to the
peptide automatically, thus avoiding the need for post-synthetic
manipulations.
[0045] After the synthesis is completed, the product is cleaved
from the solid support with a cleavage mixture containing
trifluoroacetic acid (85%):water (5%):phenol (5%):thioanisole (5%)
for six hours. The peptide-azide conjugate is precipitated with
t-butyl methyl ether and lyophilized in water/acetonitrile (2:3)
mixture. The conjugate is purified by high performance liquid
chromatography (HPLC) and analyzed with liquid chromatography/mass
spectroscopy (LC/MS).
[0046] It should be understood that the embodiments of the present
invention shown and described in the specification are only
specific embodiments of the inventors who are skilled in the art
and are not limiting in any way. Therefore, various changes,
modifications or alterations to those embodiments may be made or
resorted to without departing from the spirit of the invention and
the scope of the following claims. For example, the compounds
containing polycyclic aromatic chromophores can also be used for
optical diagnostic imaging purposes.
* * * * *