الفهرس 
Heterocyclic Synthesis and their Relevant Phosphour Esters via Phosphorus ChemistryOnly 14 pages are availabe for public view
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Abstract
Name: Reham Fawzy Barghash
Title: Synthesis of Novel Heterocycles and their Related Phosphorus Esters as well as Synthesis of Unnatural Glycosyl Amino Acids with Expected Biological Activity
Degree: Philosophy of Doctor (Ph.D.)
The thesis included two sections. In the first section, the study has been focused on phosphorus chemistry and contained two parts.
Based on the recorded pharmacological potencies of numerous substituted pyrimidines as antihyperlipemic and antihypertensive agents, synthesis of condensed and spiro bis-heterocyclic systems; oxazole-pyrimidines as well as pyrimido-oxazines; bearing a phosphonate substituent was undertaken. The methodology depended on treatment of alloxan-5-oximes with unsaturated-, active-, and resonance stabilized phosphonium salts and their phosphonate counterparts. A comparative study of the reaction of Wittig reagent and Wittig-Horner reagent is also considered. The bioassay indicated that some of the products have effect on the central nervous system (CNS), and other products have good selective anti-tumor activity and the structure-activity relationship (SAR) of new phosphonates has also been indicated.
In the second section, a new class of C-glycosyl amino acids bearing a thiourea segment as a linker has been designed and synthesized by addition of peracetylated glycosylmethyl isothiocyanates to an amine-functionalized amino acid (Nα-Fmoc-β-amino-L-alanine). Three pairs of compounds with α- and β-galacto, α- and β-gluco, and α- and β-manno configuration have been prepared with ranging yields between 70 and 75%. The orthogonal set of protective groups (O-acetyl in the carbohydrate
moiety and N-Fmoc in the amino acid residue) makes these compounds suitable substrates for the co-translational modification of natural peptides. The couplings of model hydroxy-free and perbenzylated glycosylmethyl isothiocyanates with the above Nα-Fmoc-β-amino-L-alanine and the Nα-Boc protected analogue have been carried out as well, thus broadening the scope of the coupling reaction. The study included the synthesis of a set of new sugar isothiocyanates and their coupling with the above mentioned alanine derivative.
Keywords: Alloxan-5-oximes; Alkylidenephosphoranes; Wittig-Horner carbanions; Pyrimidines, Anti-tumor activity, Structure-activity relationship (SAR); Amino acids; Glycopeptides; Glycosyl amino acids; Sugar isothiocyanate