الفهرس 
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Abstract
The present dissertation includes two parts of organic chemistry:
1- Part 1: Cytotoxic Effects of the Red Sea Soft Coral Sarcophyton
Trocheliophorum.
2- Part 2: Multi-Component Synthesis of 2-amino-4H-Chromenes
Utilizing nano-gold/zeolite as Novel Green Catalyst.
Here in the summary of the work done:
Part 1:
Soft coral organism (Sarcophyton trocheliophorum) was collected
from Red sea.
The organism was extracted using different solvent systems according
to polarity increasing.
A primary screening for cytotoxic activity using brine shrimp lethality
assay at different concentrations was done for both hexane and ethyl acetate
extracts.
This activity was used to trace the active compound(s) during the
different steps of the experimental work.
Hexane extract showed greater cytotoxicity than ethyl acetate extract.
Fractionation of the extracts was done by medium pressure liquid
chromatography (MPLC) and accelerating gradient chromatography (AGC)
over silica gel using proper gradient eluting system resulting seven fractions
of hexane extract and five fractions for ethyl acetate extract.
TLC plates sprayed with vanillin in sulfuric acid showed purple spots
indicating the possibility of terpenoids’ presence.
All fractions went under in vitro bioassay of brine shrimp lethality.
High levels of cytotoxicity in two hexane fractions and one ethyl
acetate fraction was detected while other fractions had no activity.
Part 2:
One-pot three-component synthesis of the crucial moiety 2-amino-4Hchromenes
was investigated along with the use of different catalysts.
The reaction of variant aromatic aldehyde (substituted benzaldehyde),
malononitrile and α-naphthol in ethanol under reflux in presence of a proper
catalyst to yield the corresponding 2-amino-4H-chromene derivative.
(Scheme A)
(Scheme A)
Repeating the reaction using different catalysts (Piperidine, L-Proline,
Nano-ZnO, Nano-Zeolite and Nano-Gold/Zeolite) for each substituted
aromatic aldehydes and in different reaction solvents (Ethanol, glycrol)
resulted in different product yield.
By comparing yields of the reaction, it was clear that Nanogold/
zeolite is the best used catalyst.
Using the same catalysts and reaction procedure but replacing α-
naphthol with phenol resulting in the formation of 2-amino-4H-benzopyrans
with different yields. (Scheme B)
( Another comparative evaluation for the efficacy of the different
catalysts showed the superiority of Nano-gold/zeolite over the other used
catalysts.
Another reaction direction was investigated by replacing the
benzaldehyde derivative with isatin, refluxing it with malononitrile and α-
naphthol in ethanol with catalyst variation. (Scheme C)