Objective- Breast cancer is one of the most serious problems in oncology. Alkaloids pyrrolizidine are widely found in nature and exhibited versatile biological activities. The aim of the present study was to assess anti-tumor activity of methyl 1,3-dioxo-1,1',2',3,5',6',7',7a'-octahydrospiro[indene-2,3'-pyrrolizidine]-2'-carboxylate (6) on 7,12 dimethylbenz(a) anthracene (DMBA)-induced mammary ...