الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In the present study, two medicinal plants (S. reflexcum and A.
stipularis) were investigated for its organic constitution and biological
activity with the object of discovering new chemical components of
expected biological activity. Through this investigation, the plant
material was extracted and purified by chromatographic techniques,
such as. SEPARO medium-pressure liquid chromatography (MPLC),
column chromatography (CC) (silica gel, Sephadex LH-20, reversed
phase C-18) and thin layer chromatography (TLC) (analytical and
preparative).
The isolated compounds were characterized by spectroscopic
techniques (1H NMR, 13C NMR,1H-1H COSY, TOCSY, NOESY,
HMBC, HSQCdept, DEPT, MS and GC–MS), physical data as well as
chemical transformations, and the results were analyzed and compared
with the literature data.
Pharmacological tests; in vitro anti-cancer and antischistosomiasis
tests, were used to test the activity of the extracts.
Chemical constituents of S. reflexcum (Asteraceae)
The petroleum ether extract of S. reflexcum was fractionated by
accelerating gradient chromatography (AGC) with gradient elution by
petroleum ether then with mixtures of petroleum ether, methylene
chloride and methanol. Eluted fractions were evaluated by TLC and
combined upon similar appearance, yielding seven fractions.
The fraction no 6 was eluted from the column with gradient
elution running from hexane to CH2Cl2 and MeOH in increasing
polarity to afford α-epi-lupeol [155] (37 mg).
The methanol extract of S. reflexcum was subjected to GC-MS
analysis and 4 compounds were characterized as: myristic acid ester
ENGLISH SUMMARY
13
[156], oleic acid ester [157], palmitic acid ester [158] and stearic acid
ester [159].