الفهرس 
Chapter I: IntroductionOnly 14 pages are availabe for public view
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Abstract
Chemical and biological studies on Heteroxenia species extracts (soft coral)The work described in this thesis has been undertaken with the objective of
searching for naturally occurring substances of potentially biological activities in
Egyptian soft corals. Through this investigation useful information were derived
from the application of the modern techniques of chromatography (column, and thin
layer chromatography) and spectral measurements including IR, 1D-NMR, 2DNMR
and MS.
The introductory part of this thesis comprises the literature review part
comprises detailed accounts of previously isolated natural products from some
Xeniidae (Alcyonacea) genera especially Heteroxenia species and their structural
types encountered in nature and some of their medicinal uses. Also, a brief account
of ceramides (sphingolipids), their commoner structure, methods of isolation,
identification, biosynthesis and biological importance. The theoretical part of the
thesis describes the chemical and biological investigations of chloroform extract of
Heteroxenia ghardaqensis (family Xeniidae). The original work carried out is
summarized under the following titles:
1. Isolation and identification of chemical constituents of chloroform extract of
Heteroxenia ghardaqensis.
The frozen marine organism H. ghardaqensis was broken down into small
pieces and extracted at room temperature with sufficient amount of chloroform,
several times until no further residue was obtained to ensure complete extraction.
The chloroform extract was chromatographed on silica gel (250 g) column (50 cm L
x 6 cm D), eluted with a mixture of pet ether (40-60◦C)/ EtOAc according to
increasing polarity to give eleven pure compounds (G1-G11). The structures of
isolated compounds were elucidated using chemical and spectroscopic methods
including IR, 1D, 2D-NMR and MS. These compounds were identified as the
following:
ENGLISH SUMMARY
ii
Compound (G1):
Sterol identified as gorgosten-5(E)-3β-ol using 1D, 2D-NMR, EI-MS
and spectroscopic analysis data comparing with previously reported references.
This compound was isolated for the first time from Heteroxenia ghardaqensis.