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CHEMICAL INVESTIGATION OF THE METABOLITES OF ASPERGILLUS QUADRILINEATUS AND CONSTITUENTS OF PRIMULA DENTINCULATA AND SCHWEINFURTHIA

Sultana, Viqar (1990) CHEMICAL INVESTIGATION OF THE METABOLITES OF ASPERGILLUS QUADRILINEATUS AND CONSTITUENTS OF PRIMULA DENTINCULATA AND SCHWEINFURTHIA. PhD thesis, University of Karachi, Karachi.

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Abstract

The present thesis is divided into three part. The part-1 is concerned with the chemical investigation of the metabolites of Aspergillus quadrilineatus. This has resulted in the isolation and structure elucidation of one new anthraquinone metabolite namely 7-methoxy-averufin in addition to a number of other metabolites already from other Aspergillus species, on the basis of spectral studies. 7-Methoxy averufin The part-II of thesis deals with the studies on the chemical constituents of Schweinfurthia papilionacea. The two novel macrocyclic spermine alkaloids namely 11-epi-ephedradine A (11-epi-orantine) and schweinine were isolated along with ephedradine A (oranitine) which has already been reported from Ephedra roots, but isolated for the first time from this plant. Their structure were determined by spectral and chemical studies and the stereochemistry has been assigned on the basis of 2D-nmr techniques 1. 11-epi-ephedradine A (11-epi-orantine) 2. Schweinine The part-III of the thesis describes the isolation of three new triterpenoid saponins namely primulanin, denticin and denticulatin from Primula denticulate Sm. (Primulaceae). One more saponin namely saxifragifolin B (deglucocyclamin I) was isolated for the first time from this plant although its occurrence in only two other plants Androsace saxifragifolia and Cyclamen europaeum has been reported earlier. The structures of all these saponins were determined through spectroscopic and chemical studies. These are as follows: 1. Primulanin (3-O-[β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-α-L-arabinopyranosyloxy]-16α-hydroxy-13 β,28-epoxy-olean-30-al).2. Denticin (3β-{O-β-D-glucopyranosyl-(1→4)-[O-β-D-xylopyranosyl-(1→2)]-O-β-D-glucopyranosyl-(1→4)-[ O-β-D-glucopyranosyl-(1→2)]-α-L-arabinopyranosyloxy}-16α-hydroxy-13β,28-epoxy-onean-30-al) 3. Denticulatin (3β-{O-β-D-glucopyranosyl-(1→2)-O-β-D-glucopyranosyl-(1→4)-O-β-D-xylopyranosyl-(1→4)-[O-β-D-glucopyranosyl-(1→2)]-α-L-arabinopyranosyloxy}-16α-hydroxy-13β,28-epoxy-onean-30-al)

Item Type:Thesis (PhD)
Subjects:Physical Sciences (f) > Chemistry(f2)
ID Code:1178
Deposited By:Mr. Muhammad Asif
Deposited On:03 Jan 2007
Last Modified:04 Oct 2007 21:05

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