Spectrum Chemical manufactures and distributes fine chemicals with quality you can count on including those with CAS number 90-33-5, Whether you call it 7-Hydroxy-4-methylcoumarin, 4-Methylumbelliferone or Hymecromone you can be assured the 7-Hydroxy-4-methylcoumarin products offered by Spectrum, meet or exceed the grade requirements or specifications for each individual product.