METHOD OF PRODUCING METHYL PHEOPHORBIDE (A) Russian patent published in 2013 - IPC C07D487/22 

FIELD: chemistry.

SUBSTANCE: invention relates to organic chemistry, particularly to chemistry of natural compounds and production of methyl pheophorbide (a), which is meant for synthesis of porphyrins and chlorins for photodynamic therapy purposes. The disclosed method of producing methyl pheophorbide (a) is realised as follows: extracting chlorophyll (a) from Spirulina Platensis microalgae and demetallisation thereof by treating with concentrated acetic acid while exposing the reaction mass to ultrasound at frequency 25-30 kHz for 2.0-2.5 hours at temperature of 45-50°C. The formed pheophytin (a) is then extracted by precipitation with water, after which it is methylated in a medium of tetrahydrofuran in the presence of sulphuric acid at 50-55°C for 1.0-1.5 hours; the end product is extracted by precipitation with water and purified by twofold precipitation from methylene chloride into ethanol.

EFFECT: invention significantly reduces physiological and environmental hazard of the process due to the 55-60-fold reduction of the amount of toxic methanol used, 4-5-fold reduction of the duration of the process and twofold increase in output of the product.

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