Photoresist Chemicals Olean-12-ene-28,29-dioic acid,2-(acetyloxy)-3-hydroxy-,28-methyl ester,(2â,3â,20â)- Cas：95260-98-3 Molecular Formula：Olean-12-ene-28,29-dioic acid,2-(acetyloxy)-3-hydroxy-,28-methyl ester,(2â,3â,20â)-