Photodynamic therapeutic compounds and photodynamic methods of treatment
The invention provides photodynamic therapeutic compounds and photodynamic methods of treatment. The photodynamic therapeutic compounds may be activated by long wavelength light. The photo-activation by long wavelength light may allow improved tissue penetration. The compounds are selected from the group consisting of compounds of formula (i), or a pharmaceutically acceptable salt thereof: formula (i) wherein PDC is a photodynamic core and wherein R1; R2; R3; and R4 are H, phenyl, pyridine-4-yl, methylpyridinium, N-methylpyridinium-3-yl; 2-phenyl-N-methylpyridinium-4-yl, 3-phenyl-N-methylpyridinium-4-yl, 4-phenyl-N-methylpyridinium-4-yl, 2-phenyl-N-methylpyridinium-3-yl, 3-phenyl-N-methylpyridinium-3-yl or 4-phenyl-N-methylpyridinium-3-yl; and wherein any one or more of R1, R2, R3 and R4 may be optionally substituted.
1. A compound selected from the group consisting of compounds of formula (I), or a pharmaceutically acceptable salt thereof:
Com-
pound
R4
R3
R2
R1
6
methylpyri-
methylpyri-
CH═CH2—CH3
CH═CH2—CH3
dinium-4-yl
dinium-4-yl
7
methylpyri-
methylpyri-
OH
OH
dinium-4-yl
dinium-4-yl
8
methylpyri-
Phenyl
phenyl
H
dinium-4-yl
9
methylpyri-
Phenyl
phenyl
CH3
dinium-4-yl
10
methylpyri-
Phenyl
phenyl
H
dinium-3-yl
11
methylpyri-
Phenyl
phenyl
CH3
dinium-3-yl
15,
3-phenyl-N-
phenyl
phenyl
H
and
methylpyri-
dinium-4-yl
16
4-phenyl-N-
Phenyl
Phenyl
H
methylpyri-
dinium-3-yl.
2. The compound of claim 1 wherein any two neighbouring R groups are identical.
3. The compound of claim 1 wherein the compound of formula (I) comprises far-infrared absorption spectroscopic properties to absorb far-infrared light penetrating through skin to tumour cells.
4. The compound of claim 1 wherein the compound of formula (I) blocks Ras-Raf interaction.
5. The compound of claim 1 wherein the compound of formula (I) disrupts Ras-dependent signalling.
6. The compound of claim 1 wherein the compound of formula (I) specifically targets oncogenic Ras protein in human tumour cells.
7. A pharmaceutical composition comprising an effective amount of the compound of claim 1 , and a pharmaceutically acceptable carrier, diluent and/or excipient.