Isolation and Structure Elucidation of Antiproliferative Agents From Madagascar Rainforests

Through our continuing search for anticancer agents from Madagascar rainforests as a part of International Cooperative Biodiversity Group (ICBG), we received two extracts which were active against the A2780 human ovarian cancer cell line and hence were selected for further fractionation. Six compounds were isolated from these extracts. The structure elucidation and characterization of these compounds was carried out using mass spectrometry and 1D and 2D NMR techniques. The bioassay-guided fractionation of Roupellina (Strophanthus) boivinii yielded three new and one known cardenolide glycosides. The structure of the known cardenolide glycoside was determined after comparison of NMR data to that found in literature for digitoxigenin 3-O-β-D-glucopyranosyl-(1â 4)-α-L-acofriopyranoside. All four compounds exhibited good antiproliferative activity on the A2780 bioassay. The fractionation of the extract of Grewia sp. led to the isolation of one new and one known triterpenoid. The known triterpenoid was identified as 7β-hydroxy-23-deoxojessic acid and its structure was confirmed by comparison of its 1D and 2D NMR data to that found in literature.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Chemistry

Department dc:contributor.department

Chemistry

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2007

Author dc:creator

• Karkare, Sampada S.

Chair dc:contributor.committeechair

• Kingston, David G. I.

Committee members dc:contributor.committeemember

• Brewer, Karen J.
• Carlier, Paul R.

• Strophanthus
• triterpenoids
• Grewia sp.
• Roupellina
• Grewia
• boivinide
• cardenolide glycosides
• A2780
• natural products

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

etd-09062007-000547

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/34945