Spectrum Chemical manufactures and distributes fine chemicals with quality you can count on including those with CAS number 73590-58-6, Whether you call it Omeprazole or 5-Methoxy-2-[[(4-methoxy-3 -5-dimethyl-2-pyridinyl)methyl]sulfinyl]benzimidazole you can be assured the products offered by Spectrum, meet or exceed the grade requirements or specifications for each individual product.