Carbohydrates

Monosacharides:

  • Classifies by their numbber of carbons

  • Trioses - 3 carbons

  • Pentose

    • Synthesis of RNA and DNA

  • Hexose

    • glucose

      • Is an aldohexose

      • Known as blood sugar

      • Can also be called dextrose (enantiomer)

    • Galactose

      • same as glucose but backwards

    • Fructuose

      • Levulose

      • Honey 1:1 with glucoe

      • Sweetest —> corn syrup

  • Solids at room temperature and soluble in water

  • OH and carboxyl

  • Reducing Sugar

    • Many monosacharides

    • oxidation with Benedicts Reagent

Disacharides

  • Formation happens with the release of water- condenstation

  • ANomeric carbon bonds to the OH of another carbon

  • Sucrose

    • One unit of D-glucose and one unit of D-fructose joined by

      an alpha -1,2-glycosidic bond

  • Lactose

    • Made up of D-galactose and one unit of D-glucose joined by

      a beta -1,4-glycosidic bond

  • Maltose

    • Two units of D-glucose joined by an alpha-1,4-glycosidic bond

      Formed from the hydrolysis of starch

Polysaccharides - long monosaccarade chaims om either a straign or branched conformation

Sugar forming a cyclic molecule:

  • anomeric carbon is the new stereocenter that results from this

  • Starch

    • Polymer of D-glucose

    • can be used as a thickening agent due to high OH content

    • Amylose:

      • Long chains of glucose with C 1-4 glycosidic linkages

        • 10-20% of plant starch

      • Very flexible which allows it to exist in helical conformation shapes

        • This helical shape allows it contain iodine. Iodine is therefore often used as a test

    • Amylopectin

      • Also made of long chains of glucose, but often shorter than amylose

      • Additionally, they have more rows and are not a single chaing

        • 1,4 and 1,6 every 24

      • Most plant starch is in this form

    • Glycogen

      • Animal starch; similar strutcure to amylopectin

      • 1,4 and 1,6 significantly more often

      • Located in liver and muscles 

      • Hydrolyses allows it to break into glucose providing for more energy

  • Cellulose

    • Although similar to amylose in the chains of glucose, everyother glucose is flipped over due to beta linkages

    • Rigid structure

  • Benedicts Reagent

    • Aldoses and ketoses that have an OH group on the carbon nect to the carbonyl reacto to mean a precipate Cu2O

    • All monosaccarides are reducing sugars

  • Counting Rules

    • When counting start with the carbon below the oxygen going clockwise

    • Pentoses flip

  • Glycosidic Bonds

    • Squiggly lines often significy a glycosidic bond between an alpha and beta

  • Chitin

    • Acetyl-beta-D-glucosamine joined by beta 1,4

    • found incrustacions as a matrix

QUIZ- HOW IODINE WORKS

plants get amylose and glucose not from glycogen

cellulose- plant