Pakistan Research Repository

PHOTOCHEMICAL STUDIES OF CESTRUM SPECIES (FAMILY SOLANACEAE)

Baqai, Fehmida Tasnim (1999) PHOTOCHEMICAL STUDIES OF CESTRUM SPECIES (FAMILY SOLANACEAE). PhD thesis, University of Karachi, Karachi.

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Abstract

The Cestrum species (Solanaceac) are ornamental plants with sporadic reports of their medicinal uses, C. diurnum, C. nocturnum and C. parqui, C. diurnum and C. nocturnum are cultivated in the gardens in Pakistan whereas C. aurunatiacum and C. parqui are naturalized in the Abottabad region only. The present thesis describes the isolation and structure elucidation of five new saponins namely nocturnoside A, nocturnoside B, diurnoside 1, parquisoside A and parquisoside B, as well as a known saponin karatavioside A. A known sapogenin, yuccagenin was isolated in its native form. The aglycone of the two saponins parquisoside A and parquisoside B is also a new sapogenin. It is a 24 B-hydroxy diosgenin and we have named it parquigenin. Nocturnoside, A nocturnoside B, karatavioside A and yuccagenin were isolated from the leaves and stems of C. nocturnum. Diurnoside I was isolated from the leaves and stems of C. diurnum. Parquisoside A and parquisoside B were isolated from the aerial parts of C. parqui. The plant parts of each of the species were extracted in methanol and evaporated to semi-dryness. These were partitioned between water and ethyl acetate, and then water and butanol. The ethyl acetate extract of C. nocturnum yielded yuccagenin. Butanolic extracts contained the saponins. The saponins were purified by vacuum liquid chromatography, column chromatography and finally by high pressure liquid chromatography through semi-preparative RP-18 column or preparative thin-layer chromatography using procated silica gel, glass plates. The structures of the compounds were elucidated with the help of chemical as well as spectroscopical analysis of each compound. The latter included extensive studies of various ID and 2D NMR spectral data. Diverse pharmacological properties of the crude extracts or pure saponins were also investigated. The chemical names and structures of the six saponins and the sapogenin are given below:.

Item Type:Thesis (PhD)
Uncontrolled Keywords:cestrum species, family solanaceae, c. diurnum, c. nocturnum, c. parqui, c. diurnum, c. nocturnum, c. aurunatiacum, c. parqui, nocturnoside a, nocturnoside b, diurnoside 1, parquisoside a, parquisoside b, saponins, sapogenin
Subjects:Physical Sciences (f) > Chemistry(f2)
ID Code:790
Deposited By:Mr. Muhammad Asif
Deposited On:19 Oct 2006
Last Modified:04 Oct 2007 21:02

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