Samwel, Stephen2020-07-232020-07-232003Samwel, S (2003), Oxygenated heptanoids and c-benzylflayanones from cleistochlamys kirkii and uvaria faulknerae,Master dissertation, University of Dar es Salaam. Dar es Salaamhttp://41.86.178.5:8080/xmlui/handle/123456789/13200Available in print form, East Africana Collection, Dr. Wilbert Chagula Library, Class mark (THS CHEM QK495.A6S3)The phytochemical investigations reported in this Thesis were aimed at the isolation of biologically active and other constituents from two plant species of the family Annonaceae, viz. Cleistochlamys kirkii Benth (Oliv.) and Uvaria faulknerae Verde. The two plant species belong to the genera of some Tanzanian plants that have been a focus for phytochemical investigations being carried out in the Chemistry Department at the University of Dar es Salaam. Whereas the monotypic genus Cleistochlamys was just recently included in these studies Uvaria species have been extensively investigated. Crude extracts from C. kirkii are used for the treatment of tuberculosis, rheumatism and haemorrhoid wounds in Mozambique. In these investigations C. kirkii yielded three known oxygenated heptanoids (Z)-acetylmelodorinol, melodorinol and 1,6-desoxy-(3-senepoxide, together with two hitherto new heptanoids that were named cleistenolide and cleistodienol. Acetylmelodorinol, cleistenolide and cleistodienol exhibited mild antifungal activity against Candida albicans and antibacterial activity against Staphylococcus aureus and Bacillus anthracis at a concentration of 10 mg/ml. They also showed cytotoxic activity in the brine shrimp test (LD50 values of 16.32, 90.55 and 117.89 |xg/ml, respectively). The root bark of Uvaria faulknerae yielded 5-hydroxy-7-methoxyflavanone (pinostrobin), chamanetin, dichamanetin and a mixture of uvarinol and isouvarinol, whereby chamanetin, dichamanetin, and the mixture of uvarinol and isouvarinol exhibited antibacterial activity in vitro against S. aureus and B. anthracis with a minimum inhibitory concentration of 78, 19.7 and 39.5 fig/ml, respectively. They also exhibited a strong cytotoxicity in the brine shrimp lethality test (LD50 values of 9.28, 2.50 and 2.50 fxg/ml, respectively). Pinostrobin exhibited neither antibacterial nor antifungal activity in these investigations but it showed mild cytotoxicity in the brine shrimp lethality test ( LD50 value of 132.25 ng/ml). These results demonstrate the diversity of structural frameworks among annonaceae natural products, as it has been previously observed.enPhytochemistryAnnoceaea (cleitochlamys kirkii)Chemistry analysisThesis