Phthalocyanine derivative consisting of a mixture of 4 isomers
There is described a phthalocyanine derivative of formula (I) consisting of 4 isomers wherein the relative isomer B content is less than or equal to 1% by weight.
1. An isomeric mixture of a phthalocyanine derivative of formula (I)
wherein said isomeric mixture consists of:
wherein isomer B is present in the mixture at ≤1% by weight and non-isomeric impurities are present in the mixture at a level of <0.1% by weight.
2. The isomeric mixture of claim 1 wherein the isomer B is present in the mixture at <0.2% by weight and isomer A is present in the mixture at <12.5% by weight.
3. The isomeric mixture of claim 2 wherein the isomers A/C/D are present in the mixture in the following relative contents: 5.5-7.0% (A), 56.0-63.5% (C), and 30.0-38.0% (D).
4. A pharmaceutical composition comprising the isomeric mixture of claim 2 in combination with a pharmaceutically acceptable excipient diluent or chelating agent.