A new cytotoxic and an unusual alkaloid from Buchholzia coriacea Engl. (Capparidaceae)

Buchholzia coriacea Engl. (Capparaceae) is a plant used traditionally for the treatment of diabetes, rheumatism, cold, cough and catarrh, cancer related diseases, kidney and lung pains, etc. [1]. In search of new natural product with respect to pharmaceutical lead discovery of anti cancer agents, a bioassay guided fractionation of the methanol extracts of the stem and seed of B. coriacea, led to isolation of a new (Fig. 1.3) and four known (Fig 1.1, 1.2, 1.4 and 1.5) compounds. The chemical structures of these compounds were elucidated by one and two dimensional NMR as well as high resolution mass spectrometry as acetic acid 2 -(2-benzoylamino-3-pheny-propionyllamino)-3-phenyl-propyl ester (Fig 1.1), 1-(4-hyroxy-1 H-indole-3-xyl ethanone (Fig 1.2), hexahydro-7-hydroxy-2-methyl-3-thioxopyrolo[1,2-e]imidazole-1-Bone (Fig 1.3), 2-benzamido -3-phenylpropyl benzoylphenylalaninate (Fig 1.4), and 4-(hexahydro-1-(4-hydroxy-3,5-dimethoxyphenyl)-2,6-dimethoxy phenol (Fig 1.5). All the compounds are reported for the first time from B. coriacea while compound 3 is new natural product. The cytotoxicity assay of the compounds against mouse lymphoma cell (L5178Y) revealed that compound 3 at 10 µg/mL exhibited 95% inhibition of cell growth while the other compounds at the same concentration showed poor cytotoxic activity. This new compound is currently being investigated for anticancer activity against selected cancer cell lines. The cytotoxic activity of some of the isolated compounds may explain in part the ethnomedicinal use of the plant extracts in the management of cancer and related diseases.

References:

[1] Rahmat, A. A., Mohammed I. C., Olufunso O. O. Hypoglycemic activity of Buchholzia coriacea (Capparaceae) seeds in Streptozotocin-induced diabetic rats and mice. Experimental and Toxicologic Pathology 63 (2011) 619 – 625.