Cyclization of Glucose: Formation of Pyranose

Glucose cyclization

The process where glucose transforms into a cyclic ring structure, primarily as a pyranose (6-membered ring).

Pyranose

A six-membered ring structure in cyclic monosaccharides.

Intramolecular reaction

A reaction where the hydroxyl group on the fifth carbon (C-5) attacks the carbonyl group on the first carbon (C-1).

Hemiacetal

A compound formed by the reaction of an aldehyde or ketone with an alcohol.

Chiral center

A carbon atom that has four different substituents, leading to non-superimposable mirror images.

Anomers

Stereoisomers that differ in configuration at the anomeric carbon (the carbon that was the carbonyl carbon in the open-chain form).

Alpha (α) anomer

The anomer where the new hydroxyl group at C-1 is below the plane of the ring.

Beta (β) anomer

The anomer where the new hydroxyl group at C-1 is above the plane of the ring.

Mutarotation

The interconversion between different anomers of a cyclic monosaccharide through the open-chain form.

Open-chain form

The form of glucose with an aldehyde group (C=O) at the first carbon and a series of hydroxyl groups (-OH) on other carbon atoms.

Intramolecular nucleophilic attack

The process where the hydroxyl group at C-5 attacks the carbonyl carbon at C-1.

Anomeric carbon

The new chiral center created at C-1 during hemiacetal formation.

Ring formation

The process that leads to the formation of a six-membered ring structure with the new oxygen atom bridging C-1 and C-5.

Equilibrium in solution

The state where the α and β anomers are in balance and can interconvert.

Stereoisomers

Compounds that have the same molecular formula but differ in the arrangement of atoms in space.

Carbonyl group

A functional group characterized by a carbon atom double-bonded to an oxygen atom (C=O).

Hydroxyl group

A functional group consisting of an oxygen atom bonded to a hydrogen atom (-OH).

Cyclic monosaccharide

A monosaccharide that has adopted a ring structure.

Aldehyde group

A functional group with the structure R-CHO, where R is a hydrocarbon chain.

Nucleophilic attack

A reaction where a nucleophile forms a bond with an electrophile.