Browsing Research articles (Dept of Chemistry) by Issue Date
Now showing items 21-40 of 85
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Bivarate models: relationships between solar irradiation and either sunshine duration or extremum temperatures
(Elsevier Science Ltd. www.elsevier.com/locate/renene, 2003)The Republic of Botswana is one of the sunniest countries in Southern Africa. It has very little cloud cover, insufficient rainfall, very low humidity, and very low wind speed throughout the year for most parts of the ... -
Antioxidant activity of prenylated flavonoids from the West African medicinal plant Dorstenia mannii
(Elsevier Science Ireland Ltd. www.elsevier.com/locate/jethpharm, 2003)The antioxidant activities of three prenylated flavonoids from Dorstenia mannii (6,8-diprenyleriodictyol, dorsmanin C and dorsmanin F) were compared to the common, non-prenylated flavonoid, quercetin. The prenylated ... -
Phenylpropanoid glycosides of Gnidia polycephala
(Elsevier Ltd. www.elsevier.com/locate/phytochem, 2003)Two phenylpropanoid glucosides, 2-O-b-d-glucosyloxy-4-methoxybenzenepropanoic acid and its methyl ester, together with syringin and adicardin were isolated from the stem of Gnidia polycephala and characterized by physical ... -
Prenylated flavonoids, monoterpenoid furanocoumarins and other constituents from the twigs of Dorstenia elliptica (Moraceae)
(Elsevier Ltd. www.elsevier.com/locate/phytochem, 2003)A monoprenylated flavan and two monoterpenoid substituted furanocoumarins were isolated from the twigs of Dorstenia elliptica along with 3-(3,3-dimethylallyl)-4,20,40-trihydroxylchalcone, psoralen, bergapten, O-[3-(2,2- ... -
Diprenylated chalcones and other constituents from the twigs of Dorstenia barteri var. subtriangularis
(Elsevier Ltd; www.elsevier.com/locate/phytochem, 2003)The twigs of Dorstenia barteri var. subtriangularis yielded three diprenylated chalcones: ( )-3-(3,3-dimethylallyl)-50-(2-hydroxy-3- methylbut-3-enyl)-4,20,40-trihydroxychalcone, (+)-3-(3,3-dimethylallyl)-40,50-[2000-(1 ... -
Cyclic voltammetric studies of tris(alkylisocyanide)-bis(triarylphosphine)cobalt(II) and tris-(alkylisocyanide)bis(triarylphosphine)cobalt(I) complexes exhibiting synthetic interconvertability
(NRC Research Press, http://www.nrcresearchpress.com/loi/cjc, 2003)Nine pairs of corresponding [CoI(CNR)3(PR3 ′ )2]X, [CoII(CNR)3(PR3 ′ )2]X2 complexes — where X = ClO4, BF4; CNR = CNCMe3, CNCHMe2, CNC6H11, CNCH2Ph; PR3′ = PPh3, P(C6H4Me-p)3, P(C6H4OMe-p)3 — have been studied using cyclic ... -
Antinociceptive and anti-inflammatory effects of Dorstenia barteri (Moraceae) leaf and twig extracts in mice
(Elsevier Ltd. www.elsevier.com/locate/jethpharm, 2004)The present studywas undertaken to investigate the antinociceptive and anti-inflammatory activities of the leaf and twig extracts of Dorstenia barteri (Moraceae) in mice. Both the leaf and twig extracts of Dorstenia barteri ... -
Prenylated chalcones, flavone and other constituents of the twigs of Dorstenia angusticornis and Dorstenia barteri var. subtriangularis
(Elsevier Ltd. www.elsevier.com/locate/phytochem, 2004)The twigs of Dorstenia angusticornis and Dorstenia barteri var. subtriangularis yielded 16 compounds. Two novel diprenylated chalcones: 3,50-di-(2-hydroxy-3-methylbut-3-enyl)-4,20,40-trihydroxychalcone, 3, 4-(2,2-dimeth ... -
Antimicrobial and antioxidant flavonoids from the root wood of Bolusanthus speciosus
(Elsevier Ltd. www.elsevier.com/locate/phytochem, 2004)Three new flavonoids-5,7,4'-trihydroxy-6-[1-hydroxy-2-methylbuten-2-yl]isoflavone (isogancaonin C), 7,2'-dihydroxy-4'-methoxyisoflav- 3-ene (bolusanthin III), 6,6'-dihydroxy-4'-methoxy-2-arylbenzofuran (bolusanthin IV), ... -
Viscosity behaviour of particles with non-adsorbing polymers Part III—experimental study
(Elsevier B.V. www.elsevier.com/locate/colsurfa, 2004)A series of well characterised cis-poly(isoprene) (PIP) polymers (Mw = 1180, 8000, 28 300, 31 500, 86 000, 115 000 and 130 000) have been added to dispersions of poly(12-hydroxystearic acid) (PHS) coated poly(methylmethacrylate) ... -
Epoxylignans from the seeds of Centaurea cyanus (Asteraceae)
(Elsevier Ltd. www.elsevier.com/locate/biochemsyseco, 2004)A study focusing on Centaurea cyanus L. (family: Asteraceae alt. Compositae), otherwise known as "cornflower" or "bachelor's button. The seed is purchased from B & T World Seeds sarl, Pauguignan, 34210 Olonzac, France and ... -
Characterization and Compositional Studies of the Oils from Some Legume Cultivars, Phaseolus vulgaris, Grown in Southern Africa
(AOCS Press., 2004)Seed oils from six legume cultivars of Phaseolus vulgaris, grown in the Kingdom of Lesotho, were extracted and their physicochemical properties and FA compositions were determined in order to compare their dietary lipids ... -
Trace enrichment of metal ions in aquatic environments by Saccharomyces cerevisiae
(Elsevier; www.elsevier.com/locate/talanta, 2004)[Please note that chemical formulae do not display correctly in this abstract]. Sorption properties of baker's yeast cells, characterised as Saccharomyces cerevisiae were evaluated for trace enrichment of metal ions: Cd2+, ... -
Stereoselective routes to 3-hydroxy and 3,4-dihydroxy derivatives
(Elsevier Ltd; www.elsevier.com/locate/tetlet, 2004-06-21)The Diels-Alder adduct of ethyl (E)-3-nitroacrylate and furan provides a versatile template for the stereoselective synthesis of mono and dihydroxylated derivatives of 2-aminocyclohexanecarboxylic acid (ACHC). The ... -
Antimicrobial and radical scavenging flavonoids from the stem wood of Erythrina latissima
(Elsevier Ltd; http://www.elsevier.com/wps/find/journaldescription.cws_home/273/description, 2004-11-20)From the stem wood of Erythrina latissima, two isoflavones and a flavanone were isolated and characterized as 7,3'-dihydroxy-4'-methoxy-5'-(y,y-dimethylallyl)isoflavone (erylatissin A), 7,3'-dihydroxy-6".6"-dimethyl-4".5 ... -
Isoflavonoids from Seeds of Millettia griffoniana (Bail), 15
(Verlag der Zeitschrift fu¨r Naturforschung, Tu¨bingen · http://znaturforsch.com, 2005)Three new isoflavonoids, griffonianone F, G and H were isolated from the seeds of Millettia griffoniana, along with the known prebarbigerone, pseudobaptigenin, pseudobaptigenin methyl ether, tephrosin, dipterixine, ... -
The first 60-O-sulfated phenylanthraquinones: isolation from Bulbine frutescens, structural elucidation, enantiomeric purity, and partial synthesis
(Elsevier Ltd.http://www.elsevier.com/wps/find/journaldescription.cws_home/942/description#description, 2005)From the roots of Bulbine frutescens, the first sulfated phenylanthraquinones were isolated, together with their known sulfate-free analogs. Their structures were elucidated by spectroscopic and chiroptical methods, by ... -
Antitrichomonal and antioxidant activities of Dorstenia barteri and Dorstenia convexa
(Brazilian Journal of Medical and Biological Research. http://www.scielo.br/scielo.php?pid=0100-879X&script=sci_serial, 2005)Dorstenia barteri and D. convexa extracts and some isolated components of the former were investigated for effectiveness against Trichomonas gallinarum and compared with quercetin and quercitrin. The antioxidant activity ... -
Identification of Cu and Ni indicator plants from mineralised locations in Botswana
(Elsevier www.elsevier.com/locate/jgeoexp, 2005)Plant species that accumulate high levels of metals in proportion to the metal content in the soil are of considerable interest in biogeochemical and biogeobotanical prospecting. This study was aimed at investigating ... -
Prenylated flavonoids and other constituents from the twigs of Dorstenia angusticornis (Moraceae)*
(Elsevier Ltd. www.elsevier.com/locate/biochemsyseco, 2005-06-18)Dorstenia (Moraceae) is a mainly tropical genus of some 170 species (Mabberley, 1987). There are 23 species in Cameroon where a decoction of the leaves is administered for the treatment of cough, headache and stomach ...