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STUDIES ON THE CHEMICAL CONSTITUENTS OF THE FRUIT OF GUAIACUM OFFICINALE LINN. AND SOME MARINE ORGANISMS

din, Shafi ud (1990) STUDIES ON THE CHEMICAL CONSTITUENTS OF THE FRUIT OF GUAIACUM OFFICINALE LINN. AND SOME MARINE ORGANISMS. PhD thesis, University of Karachi, Karachi.

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Abstract

The present research work is carried out in two parts. Part-I deals with the isolation and characterization of triterpenoid saponins from the fruit of Guaiacum efficinale Linn. (Zygophyllaceae). The column chromatography of biologically active n-butanolic extract of the fruit of G.officinale Linn. Yielded seven new triterpenoid saponins, guaianin F,G.H,I,J,K and L. All of these saponins were purified on HPLC and their structures were elucidated by the help of spectroscopic methods and chemical reactions as 3-0(aL-rhamnophyranosyl (1-3) a L-rhamnophyranosyl (1-2)a-L-arabinopyranosyl (3-1) B-D-glucopyranosyl)-30 norolean-12,20(29)-dien-28-oic acid 28-0 (B-D-glucopyranosyl (1-6) B-D-glucopyranosyl)ester (I), 3-0(a-L-rhamnopyranosyl(1-3) rhamnophranosyl (1-2) a-L arabinopyranosyl (3-1) B-D-glucopyranosly) oleanolic acid 28-0 (a-D-glucopyranosyl (1-6) B-D-glucopyranosly) easter (2) 3-0(a-L-rhamnopyranosyl (1-3) a-L-arabinopyranosyl) oleanolic acid (3) 3-0 (a-L-rhamnopyranosyl(1-2) a-L-rhamnopytranosyl(1-2) a-L-arabinopyranosyl(1-3)B-D-glucuronopyransosyl)oleanolic acid-28-0 (B-D-glucopyranosyl(1-6) B-D-glucopyranosyl) ester (4), 3-0 –(a-L-arabinopyranosyl (1-3) B-D-glucuronopyranosyl) oleanolic acid 28-0-(a-L-rhamnopyranosyl (1-2) a-L-rhamnopyranosyl (1-4)B-D-glucopyranosyl (1-6) B-D-glucopyranosyl) easter (5), 3-0 (B-D-glucuronopyranosyl) oleanolic acid 28-0 (a-L-rhamnopyranosyl (1-2) a-L-rhamnopyranosyl (1-2) a-L-arabinopyranosyl (3-1) B-D-glucopyranoslyl) (1-3) B-D-glucopyranosyl) ester (6) and 3-0 (B-D-glucopyranosyl (1-4) B-D-glucuronopyranosyl(3-1) a-L-arabinopyranosyl) oleanolic acid 28-0(a-L-rhamnopyranosyl (1-6) B-D-glucopyranosyl (1-6) B-D-glucopyranosyl)ester (7), respectively. Part II deals with the isolation and characterization of the chemical constituents of following marine organisms. a).Halymenia porphyroides (red alga) b).Endarachne binghamiae (brown alga) c).Astropecten indicus (star fish) The column chromatography of ethyl acetate extract of H.porphyroides yielded a new N-acyl sphingosine, Halyminine (8) which was purified, after acetylation, on a silica gel column and the structure of 8 was determined by spectroscopic methods. The same column also afforded sterols and fatty acids, identified by spectral data as cholesterol (9), 7-oxo-cholesterol (10) methyl ester of hexadecanoic acid (11). Bexadecanoic acid (12) and hexadec 5-enic acid (13). The compounds 9 and 10 were purified on preparative TLC while the compounds 11-13 were obtained in pure form. All of these compounds have been isolated for the first time from the same source. The column chromatography of ethyl acetate fraction of E. binghamiae (brown alga), yielded three known sterols, which were identified by means of spectroscopy as 24-methylene cholesterol (14), 24-methyl cholesta 5,25 dien 3B ol (15) and 24 hydroxy, 24,vinyl cholesterol (16). The compound 14 was purified on preparative TLC while the compounds 15 and 16 were purified on a silica gel column. The compounds 14-16 have not been reported from the same source, so far. The column chromatography of chioroform sox-extract of A.indicus (star fish)afforded a crude sterol mixture, which was purified on HPLC. Thepurification led to the isolation of four known sterols, which were identified on the basis of spectral evidences as cholesta-7,22-dien 3B-ol (17) 24-methylene cholesta 7 en-3B-ol (18). 24-methyl cholesta 7-22-dien 3B-ol (19) and cholesta-7 en 3B-ol(20). All of these sterols have not been reported from the same source, so far

Item Type:Thesis (PhD)
Uncontrolled Keywords:saponins, guaiacum officinale linn, triterpenoid saponins, guaianin f(1), guaianin g(2), guaianin h(3), guaianin i(4), guaianin j(5), guaianin k(6), guaianin l(7), star fishes, halymenia porphyroides, endarachne binghamiae, astropecten indicus
Subjects:Physical Sciences (f) > Chemistry(f2)
ID Code:791
Deposited By:Mr. Muhammad Asif
Deposited On:19 Oct 2006
Last Modified:04 Oct 2007 21:02

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