Т Е М А: УГЛЕВОДЫ . i. МОНОСАХАРИДЫ...2014/11/14 · Т Е М А:...
TRANSCRIPT
T e m a
GLUCIDELE
(HIDRAŢII DE CARBON).
MONOZAHARIDELE.
C
O
H
C H O H ) n
C H 2 O H
(
CH2OH
C=O
CHOH)n(
CH2OH
Aldoze ( n = 1,2,3…) Cetoze ( n = 1,2,3… )
Stereoizomeria monozaharidelor
C
O
H
CH2OH
OH
H
H
H
HO
HO
HHOH OH
C
O
H
CH2OH
OH
OH
HHO
H
H
D - Glucoza L - Glucoza
Pentozele
C
CH2
CH2OH
OHH
OHH
O
HC
CH2OH
OHH
OHH
O
H
HHO
C
CH2OH
OHH
OHH
O
H
HHO
C
CH2OH
OHH
OHH
OHH
O
H
D-Riboza D-Xiloza D-Arabinoza D-Dezoxiriboza
Hexozele
C
OHH
OHH
O
H
HHO
CH2OH
OHH
C
O
H
CH2OH
OHH
C
OHH
O
H
CH2OH
OHH
HHO
HHO
OHH
CH2OH
C=O
CH2OH
OHH
HHO
HHO
HHO
OHH
D-Glucoza D-Manoza D-Galactoza D-Fructoza
C
H
OHH
O
H
HHO
CH2OH
OHH
NH2
C
O
H
CH2OH
OHH
HHO
HHO
H NH2
D-Glucozamina D-Galactozamina
Tautomeria oxo-ciclică a monozaharidelor
C
H
OHH
O
H
HHO
CH2OH
OHH
OH
C
H
OHH
H
HHO
CH2OH
H
OH
HO
O
C
H
OHH
HHO
CH2OH
H
OH
O
OHH
β-D-Glucoza D-Glucoza α-D-Glucoza
O O
Ciclu piranozic Ciclu furanozic
C
H
O
H
OH
HHO
OHH
CH2OH
OHH
O
CH2OH
HH
OH
H
H
OH
H
OHO
O
CH2OH
HH
OH
H
H
OH
OH
HOH H
α-D-Glucopiranoza D-Glucoza β-D-Glucopiranoza
C
H OH
H OH
H OH
CH2OH
O H
O H
OHH
OH
H
OH
C
H
HO H2 H2HO O OH
HH
OH
H
OH
C
H
α-D-Ribofuranoza D- Riboza β-D-Ribofuranoza
OHH
CH2OH
OHH
HHO
C=O
CH2OHOCH2
H H
OH
O
H
CH2OH
OH
HO
H H
HO OCH2
H H
OH
O
H
OH
CH2OH
α-D-Fructofuranoza D-Fructoza β-D - Fructofuranoza
O
H
H
OH
H
H
OH
H
HO
HOCH2OH CH2OH
O
H
HH
H
OH
HO
HO
H
OH
α-D-Glucopiranoza β-D- Glucopiranoza
Proprietățile chimice ale monozaharidelor
1.Formarea și hidroliza glicozidelor
O
CH2OH
HH
OH
H
H
OH
H
OHOH
HO CH3+HCl
O
CH2OH
HH
OH
H
H
OH
H
O O CH3
+ H2O(c)
α-D-Glucopiranoza O-Metil-α-D-glucopiranozidă
O
CH2OH
HH
OH
H
H
OH
H
OHOH
O
CH2OH
HH
OH
H
H
OH
H
O O CH3
+ H2OH+
+ CH3OH
H
O-Metil-α-D-glucopiranozidă α-D-glucopiranoza
2. Formarea și hidroliza eterilor
α-D-Glucopiranoza О-Metil-2,3,4,6-α-D-tetrametil-
glucopiranozidă
O
HH
H
H
H
O CH3
CH2OCH3
OOCH3
OCH3
+ H2OH+
+ CH3OH
CH3
O
HH
H
H
H
CH2OCH3
OOCH3
OCH3
OHCH3
О-Metil-2,3,4,6-tetrametil- 2,3,4,6-Tetrametil- α-D-
α-D-glucopiranozidă glucopiranoza
+ H2OO4S+ Na2NaOH
CH3
+ (CH3)SO4
O
HH
H
H
H
O CH3
CH2OCH3
OOCH3
OCH3
O
CH2OH
HH
OH
H
H
OH
H
OHOH2
3. Formarea și hidroliza esterilor
+ 5 CH3COOH
CH3OC
O
HH
H
H
H
CH2OCOCH3
O
OCOCH3
OCOCH3
OCOCH3
+ 5 (CH3CO)2O
H
O
CH2OH
HH
OH
H
H
OH
H
OHO
α-D-Glucopiranoza Pentaacetil-α-D-glucopiranoza
+H2O (H )+ 5 CH3COOH
CH3OC
O
HH
H
H
H
CH2OCOCH3
O
OCOCH3
OCOCH3
OCOCH3
H
O
CH2OH
HH
OH
H
H
OH
H
OHO
Pentaacetil-α-D-glucopiranoza α-D-Glucopiranoza
6-Fosfat de glucoză 6-Fosfat de fructoză
1,6-Difosfat de fructoză
Fosfați de monozaharide
O
CH2O
HH
HOOH
H
H
OH
H
OH
PO3H2
O
CH2OPO3H2
OH
O
CH2OH
H
O
CH2OPO3H2
OH
O
CH2OPO3H2
H
O
O
OH
OH
OH
CH2OH
H
ATP ADP
Hexochinaza
O
O
OH
OH
OH
CH2OPO3H2
H
Mg2+
Glucopiranoza Glucopiranozo-6-fosfat
O
O
OH
OH
OH
CH2OPO3H2
H Glucozo - 6 - fosfatizomeraza
O
CH2OPO3H2
OH
O
CH2OH
H
Glucopiranozo-6-fosfat Ffructozo-6-fosfat
ATP ADP
Mg2+
O
CH2OPO3H2
OH
O
CH2OH
H
O
CH2OPO3H2
OH
O
CH2OPO3H2
H
6 - Fosfatfructokinaza
Ffructozo-6-fosfat Ffructozo-1,6-difosfat
Oxidarea și reducerea monozaharidelor
De exemplu, oxidarea glucozei:
OHH
CH2OH
OHH
C
H
O
H
OH
HHO
OHH
CH2OH
OHH
C
H
O
OH
HHO
OH
Br2 (H2O)
D - Glucoza Acidul-D-gluconic
OHH
CH2OH
OHH
C
H
O
H
OH
HHO
OHH
OHH
COOH
HNO3 (p)
H OH
HHO
COOH
D - Glucoza Acidul-D-glucaric
OHH
CH2OH
OHH
C
H
O
H
OH
HHO
OHH
OHH
COOH
H OH
HHO
H
O
HH
OH
H
H
OH
OH
HO
COOHC
O
H
О - enzimă
D -Glucoza Acidul-D-glucuronic
Reducerea monozaharidelor:
C
H
O
H
OH
HHO
OHH
CH2OH
OHH
OHH
CH2OH
OHH
H OH
HHO
CH2OH
NaBH4
D - Glucoza D - Sorbitol
Schema sintezei acidului ascorbic:
OHH
CH2OH
OHH
H OH
HHO
CH2OH
C=O
CH2OH
HHO
OHH
CH2OH
HHO
OHH
CH2OH
HHO
C=O
HHO
COOH
H
CH2OH
HHO
C=O
HHO
C
O
O
O O
D-Sorbitol L-Sorboza Acidul-2-oxo-L-gulonic γ-Lactona
(Vit.С)
H
CH2OH
HHO
C
O
O
C
C OH
OH
O
O
OH
CH(OH)CH2OH
H
HO
Acidul-L-ascorbic (Vit.С ) .
O
OHHO
O CH CH2
OH
OHO
H
OO CH CH2
OH
OH
O O
Acidul ascorbic Acidul dehidroascorbic
+
CH3CONH
O
H
CHOH
HH
OH
H
H
COOH
OH
CHOH
CH2OH
OHH
CH2OH
OHH
H
HCH3CONH
OHH
CH2
C
COOH
O
OH
OHH
CH2OH
OHH
HHO
HCH3CONH
OHH
CH2
C
COOH
O
COOH
C
CH3
O
C
OHH
O
H
CH2OH
OHH
HHO
HCH3CONH
N-Acetilmanozamina Acidul neuraminic