Glucose (also known as dextrose
or blood sugar
is a monosaccharide
- formula C6
It is an example of a 6-carbon (hexose) sugar
Notice the 6 carbon atoms (grey)
forming the backbone of the molecule, and the oxygen atom (red)
in the ring.
The hydrogen atoms (white) are either attached directly to the carbons
, or via oxygen as OH groups
- at an angle.
The glucose molecule can form into other configurations, but this structure - a ring or chair form - is the most stable and therefore most common in biological systems.
The ring itself is 6-sided
, but only 5 of its corners are made up by carbon atoms.
Only the carbon outside the ring (number 6) has 2 single hydrogens and an OH group.
The glucose molecule in this form is known as α-D-glucopyranose, as the central part of the molecule is similar to pyran - a six-membered heterocyclic ring-shaped compound with five carbon atoms and one oxygen.
It is in equilibrium with a open-chain form in which Carbon 1 forms a CHO aldehyde group
which gives it reducing properties, so that it reacts with reagents such as Benedict's.
Glucose is a component of other biological molecules: maltose, lactose, sucrose, cellobiose, amylose, amylopectin, glycogen.
See the carbohydrates section of the 3-D molecules index, above.