الفهرس 
Synthesis of C-nucleosidesOnly 14 pages are availabe for public view
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Abstract
The first part of this work is concerned with the synthesis of new azepanones rings. In the second part, some of these new azepanones and their analogues have been used to synthesis N-nucleosides and C-nucleosides. The synthesis of 3,3-dichloro-N-Tos yl-azepane-5-one (92) is summarised in scheme [20]. Initial reaction of p-Tosylsulphonarnide with 2,3- dichloropropene afforded both the monoalkyl and dialkyl addition products (86) and (87) respectively which were then reacted with methylacrylate to afford (88). Saponification of (88) in ethanolic sodium hydroxide gave acid (89) . Conversion of the acid followed by Freidel Crafts cyclization afforded (92). Dichloroazepanone (92) was used as the parent compound for further f unctianal group interconversion . Thus the monochloro compound (93) and methoxy compound (94) were obtained from the dichloroazepanone by the action of the sodium bicarbonate in water and methanol respectively. When compound (93) was reacted with a strong electrophilic reagent DC1, exchange of the proton alpha to carbonyl group (97) was obsrved. This suggested that C-nucleoside may be formed by attachment of protected halo- sugars at this carbon atom. Benzyl bromide was chosen due to its size being comparable with sugars, various base conditions were used but no reaction was observed. However, when deprotantion using LDA followed by addition of a silylating reagent and a Lewis acid catalyst give unexpected product (99). A similar reaction on the methoxy compound failed. The catalytic reduction of(92) in ethanol and Pd/ charcoal, 10% afforded two products (96a) and (96b). Reaction of (93) and (94).