James D Olowokudejo

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The isolation of three naphthylisoquinoline alkaloids from the leaves of Ancistrocladus guineënsis is described. Their complete structures were established by spectroscopic, chiroptical and degradative methods. Thus, two hitherto unknown 5,8'-coupled naphthylisoquinoline, named ancistroguineines A and B, were isolated, constituting the first example of a(More)
Chromosome counts were determined for 46 populations ofBiscutella representing 28 taxa. The genus was found to contain diploid taxa with 2n = 12, 16 and 18, tetraploid taxa with 2n = 36 and hexaploid taxa having 2n = 54.B. laevigata L. s. l. consists of diploid and tetraploid populations which are poorly differentiated morphologically. TetraploidB.(More)
Leaf indumentum characteristics of 52 taxa of the genusBiscutella are examined by hand lens, stereo- and scanning electron microscopy. Hairs occur on all vegetative organs of all taxa exceptB. laevigata subsp.lucida which is completely glabrous and shining. Trichomes are simple unicellular and attenuate but are variable in structure, size and distribution(More)
Uraria picta leaf-pair unrolling inside out is a remarkable feat. A leaf-pair was investigated to understand the mechanism of spontaneous reverse inside out act of the plant. The upper (adaxial) and lower (abaxial) surfaces of the leaf-pair were examined using scanning and light microscopy. The scan showed diversity of hairs varying in shape from straight,(More)
A study was made of the morphological variation in seven population samples ofB. glacialis. Data on quantitative and qualitative characters reveal that one of the populations differs considerably from the rest. Observations on geographical distribution show that this species is not endemic to the peaks of Sierra Nevada but far more widely distributed than(More)
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