Browsing Faculty of Science & Technology (FST) by Author "Yenesew, Abiy"
Now showing items 21-40 of 55
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Bioactivity of 'Flemingin A' and other Natural Products from the leaves of Flemingia grahamiana
(Department of Chemistry; Kyambogo University,Department of Chemistry, University of Nairobi,Department of Chemistry, University of Gothenburg,, 2011)Flemingia graharriiana (Wight & Arn.) is an erect herb or sub-shrub up to 1.8 m tall with deep (sometimes tuberous) roots and 3-foliate alternate leaves. It is distributed in Tropical Africa and occurs in open and wooded ... -
Busseihydroquinones A-D From The Roots Of Pentas Bussei
(University of NairobiDepartment of Chemestry, 2012-07)Four new naphthohydroquinones, named busseihydroquinones A−D (1−4), along with a known homoprenylated dihydronaphthoquinone (5), were isolated from the CH2Cl2/MeOH (1:1) extract of the roots of Pentas bussei. Although the ... -
Chemotaxonomic significance of anthraquinones in the roots of asphodeloideae (asphodelaceae)
(1995)The distribution of seven anthraquinones in the roots of some 46 species belonging to the genera Asphodelus, Asphodeline, Bulbine, Bulbinella and Kniphofia was studied by TLC and HPLC, 1,8-Dihydroxyanthraquinones based on ... -
The chemotaxonomic significance of root anthraquinones and pre-anthraquinones in the genus Lomatophyllum (asphodelaceae)
(University of NairobiDepartment of Chemistry, Addis Ababa UniversityDepartment of Botany, Rand Afrikaans UniversityCollege of Biological and Physical Sciences,University of Nairobi, 1995-11)The roots of seven species of Lomatophyllum were analysed by TLC and HPLC for the presence of nine different anthraquinones and pre-anthraquinones which are all known to be characteristic constituents of the subterranean ... -
Chemotaxonomic survey of anthraquinones and pre-anthraquinones in roots of Aloe species
(University of NairobiCollege of Biological and Physical Sciences, 1995-04)Root samples from 172 species of Aloe were surveyed by TLC and HPLC for the presence of anthraquinones and pre-anthraquinones. With the exception of the three species of the series Serrulatae, 1,8-Dihydroxyanthraquinones ... -
A comparative study of anthraquinones in rhizomes of Kniphofia species
(University of NairobiDepartment of Chemistry, Addis Ababa UniversityCollege of Biological and Physical Sciences,University of Nairobi, 1988-01-14)The anthraquinone content of eight kniphofia species was compared using reversed phase HPLC method coupled with a photodiode array detector. -
Constituents of the Roots and Leaves of Ekebergia capensis and Their Potential Antiplasmodial and Cytotoxic Activities
(2014)A new triterpenoid, 3-oxo-12β-hydroxy-oleanan-28,13β-olide (1), and six known triterpenoids 2–7 were isolated from the root bark of Ekebergia capensis, an African medicinal plant. A limonoid 8 and two glycoflavonoids 9–10 ... -
Crystal Structures and Cytotoxicity ofent-Kaurane-TypeDiterpenoids from TwoAspiliaSpecies
(University of Nairobi, 2018)A phytochemical investigation of the roots ofAspilia plurisetaled to the isolationofent-kaurane-type diterpenoids and additional phytochemicals (1–23).The structures ofthe isolated compounds were ... -
Flavonoids and isoflavonoids from Tephrosia fulvinervis and Tephrosia pentaphylla
(University of NairobiCollege of Biological and Physical Sciences, 1989)From the roots, leaves and pods of Tephrosia pentaphylla three new 6-oxygenated rotenoids (dihydrostemonal, 9-demethyldihydrostemonal and 6-acetoxydihydrostemonal) were isolated and characterized. In addition six known ... -
Flavonoids from the seed pods of Tephrosia pumila
(University of NairobiDepartment of Chemistry, Addis Ababa UniversityPhytochemistry Research Laboratories, Department of Pharmacy (Pharm. Chem.), University of StrathclydeCollege of Biological and Physical Sciences,University of Nairobi, 1989)Inaddition to the known pumilaisoflavones A and B two further isoflavonoids have been isolated from the seed pods of Tephrosia pumila collected in Ethiopia. These have been characterized, on the basis of spectral analysis, ... -
Flemingins G–O, Cytotoxic and Antioxidant Constituents of the Leaves of Flemingia grahamiana
(2014)The known flemingins A–C (1–3) and nine new chalcones, named flemingins G–O (4–12), along with deoxyhomoflemingin (13) and emodin (14) were isolated from a leaf extract of Flemingia grahamiana. The isolated chalcones were ... -
Four isoflavones from seed pods of Millettia dura
(University of NairobiCollege of Biological and Physical Sciences, 1996-02)Seed pods of Millettia dura yielded four novel isoflavones, which have been characterized as 3-(3,4-dimethoxyphenyl)-6-methoxy-8,8-dimethyl-4H,8H-benzo[1,2-b: 3,4-b′]dipyran-4-one (trivial name, durallone), 6-demethyldurallone, ... -
Four isoflavones from the stem bark of erythrina sacleuxii
(University of NairobiDepartment of Chemistry, University of Nairobi, 1998-09-03)From the stem bark of Erythrina sacleuxii four new isoflavones were isolated and characterized as 5,7-dihydroxy-2′,4′,5′-trimethoxyisoflavone (trivial name, 7-demethylrobustigenin), 5,7-dihydroxy-4′-methoxy3′-(3-methylbu ... -
Friedelane triterpoids from rawsonia lucida
(Department of Chemistry, University of Nairobi,Department of Pharmacology and Pharmacognosy, University of Nairobi,, 2010)Rawsonia lucida (Flacourtiaceae) is an evergreen tree or shrub that is mainly distributed in tropical and southern Africa. Recent survey of plants traditionally used for the treatment of malaria have shown that the ... -
Isoflavanones and 3-Methoxyflavones from the Stem Bark of Platycelphium voense
(Department of Chemistry, Kyambogo University,Department of Chemistry, University of Nairobi,Department of Chemistry, University of Gothenburg,School of Pharmacy, University of Nairobi,, 2011)Platycelphium (Engl.) Wild (Leguminosae) is a monotypic genus that occurs in the drier parts of Eastern Africa (Gillett et 01., 1971). Prior to this report, the only phytochemical studies on Platycelphium voense describe ... -
Knipholone anthrone from Kniphofia foliosa
(University of NairobiCollege of Biological and Physical Sciences, 1993-11)A new anthrone named knipholone anthrone was isolated from the stem of Kniphofia foliosa. Its structure was determined by spectral analysis as well as conversion to knipholone. -
Knipholone cyclooxanthrone and an anthraquinone dimer with antiplasmodial activities from the roots of Kniphofia foliosa
(Department of Chemistry, 2013)A new phenylanthrone, named knipholone cyclooxanthrone and a dimeric anthraquinone, 10-methoxy-10,7′-(chrysophanol anthrone)-chrysophanol were isolated from the roots of Kniphofia foliosa together with the rare naphthalene ... -
Larvicidal Activities Of Extracts And Rotenoids From Millettia Usaramensis Subspecies Usaramensis On Aedes Aegypti (Linnaeus, 1762) (Diptera: Culicidae)
(University of Nairobi, 2014)The dichloromethane/methanol (1:1) extract of the stem bark of Millettia usaramensis subspecies usaramensis was tested for its larvicidal activity against the 4th instar Aedes aegypti larvae and demonstrated activity with ... -
LC-MS-Based Metabolomics for the Chemosystematics of Kenyan Dodonaea viscosa Jacq (Sapindaceae) Populations
(University of Nairobi, 2020)Dodonaea viscosa Jacq (Sapindaceae) is a medicinal plant with a worldwide distribution. The species has undergone enormous taxonomic changes which caused confusion amongst plant users. In Kenya, for example, two varieties ... -
Medicinal plants of East Africa: An Illustrative Guide
(physical and biological sciences, 2010)
