Synthetic reactions of aldonolactones
This chapter examines the synthetic reactions of aldonolactones. Aldonolactones are useful starting materials for the synthesis of modified sugars. They have also been used as chiral templates in the synthesis of natural products. The hydroxyl groups of aldonolactones react with a variety of aldehyd...
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| Autores principales: | , |
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| Formato: | SER |
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| Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_00652318_v50_nC_p125_DeLederkremer |
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| Sumario: | This chapter examines the synthetic reactions of aldonolactones. Aldonolactones are useful starting materials for the synthesis of modified sugars. They have also been used as chiral templates in the synthesis of natural products. The hydroxyl groups of aldonolactones react with a variety of aldehydes and ketones to give the corresponding acetal derivatives. D-Ribono-1,4-lactone readily condenses with acetone, under acidic catalysis with mineral acids or anhydrous copper sulfate, to give 2,3-O-isopropylidene-D-ribono-1,4-lactone that was employed for the synthesis of 5-deoxy and 5-O-substituted derivatives of D-ribono-1,4 lactone. The reaction of aldonolactones with hydrogen bromide in acetic acid has been extensively studied. The treatment of D-galactono-1,4-lactone with HBr–AcOH for a few hours at room temperature followed by acetylation gave the acetylated 6-bromo-6-deoxy derivative in good yield. The addition of organometallic reagents to the carbonyl group of conveniently substituted aldonolactones constitutes a viable chain-extension method. It is found that the reaction leads to the formation of hemiacetals of glyculoses, 1-methylene sugars, and C-glycosyl compounds, which are precursors of, or occur as subunits of, a variety of natural products. © 1994, Academic Press Inc. |
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