METHOD OF PURPURIN-18 PREPARING Russian patent published in 1996 - IPC

FIELD: chemical-pharmaceutical industry. SUBSTANCE: purpurin-18 is obtained by extraction of chlorophyll derivatives from plant raw, their oxidation in spirituous alkali medium using air oxygen. Formed unstable chlorine then converted to the end product followed by its purification on silica gel and crystallization. Method involves the use of medicinal preparation sewage after their extraction from the plant raw. Chlorophyll derivatives were extracted with C₂-C₅-alcohols, and conversion of unstable chlorine is carried out by its treatment with acid up to pH below 1.5. Before purification on silica gel the end product id defatted with nonpolar solvent and extracted with chloroform. Method ensures to obtain pure product (purity is 92-95%). EFFECT: increased yield, simplified method, improved ecology. 3 dwg