Spectrum Chemical manufactures and distributes fine chemicals with quality you can count on including those with CAS number 53-03-2, Whether you call it Prednisone, 1 -2-Dehydrocortisone , 17 -21-Dihydroxypregna-1 -4-diene-3 -11 -20-trione , Deltadehydrocortisone or 17alpha -21-Dihydroxypregna-1 -4-diene-3 -11 -20-trione you can be assured the Prednisone products offered by Spectrum, meet or exceed the grade requirements or specifications for each individual product.