| Term | Definition |
|---|
| carbohydrates | are polyhydroxy aldehydes and ketones, commonly called sugars. |
| simple sugars | monosaccharides, are carbohydrates like glucose and fructose that cant be converted into smaller sugars by hydrolysis. |
| complex carbohydrates | are made of two or more simple sugars linked together. |
| fischer projection | a standard means of representing stereochemistry at chirality centers, particularly in carbohydrate chemistry. |
| d sugars | naturally occurring sugars that have the hydroxyl group at teh bottom chirality center pointing to the right (R configuration). |
| L sugars | have an S conficuration at the lowest chirality center, with the bottom -OH group pointing to the left. |
| pyranose | results from intramolecularnucleophilic addition of the -OH group at C5 to the C1 carbonyl group. 6 member ring |
| furanose | results from addition of the - OH group at C5 to the C2 carbonyl. 5 member ring |
| anomers | when an open chain mono-saccharide cyclizes to a pyranose or furanose form, a new chirality center is generated at teh former carbonyl carbon. two diasteriomer, called ----------. |
| anomeric carbon | normally refers to carbon 1. |
| alpha anomer | the minor anomer, which has the -OH group at C1 trans to the -CH2OH substituent at C5. axial |
| beta anomer | the major anomer, which has the -OH group at C1 cis to the -CH2OH substituent at C5. equitorial |
| mutarotation | change in optical rotation due to the slow conversion of the pure anomers into 37:63 equilibrium mixture. it occurs by a reversible ring opening of each anomer to the open chain-aldehyde, follow by reclosure. |
| glycosides | carbohydrate acetals. named by replacing-ose with - oside. they dont show mutarotation. |
| alditol | treatment of an aldose or ketose with NaBH4 reduces it to a polyalcohol called an -------- |
| aldonic acids | when an aldose or ketose becomes oxidized. |
| reducing sugars | tollen's (Ag+ in ammonia), Fehling's (Copper 2+ in aqueous sodium tartrate), and Benedict's(copper2+ in sodium citrate) reagents are tests for these type of sugars. these sugars reduce the metal oxidizing reagent. |
| Wohl degredation | this reaction shortens an aldose chain by one carbon. H2NOH |
| Kiliani-fischer synthesis | this reaction results in the lengthening of an aldose chain by one carbon atom. HCN, H2, H3O+ |
| 1,4' link | a glycosidic bond between C1(anomeric carbon) of the first sugar and the -OH at the C4 of the second sugar. |
| polysaccharides | are complex carbohydrates in which tens, hundreds, or even thousands of simple sugars are linke together through glycoside bonds. theyre not reducing sugars and dont show mutarotation. |
| cellulose | polysaccharide consisting of beta-D-glucose monomers that reinforces plant-cell walls. |
| starch | polysaccharide in plant cells that consists entirely of alpha-D-glucose monomers. |
| deoxy sugars | have an oxygen atom missing |
| amino sugars | have an -OH group replaced by an -NH2. |
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