MCAT Ochem

Epimers v.s. Anomers

D v.s. L conformation for monosaccharide

Alpha and Beta monosaccharide conformation

Glucose cyclization, which carbon/hydroxyl attacks which carbon?

In alpha form, does OH point up or down?

In beta form, does OH point up or down?

Hydroxyl on C5 attacks C1

Where is the anomeric carbon? Define it.

Carbon atom in a cyclic carbohydrate that was the carbonyl carbon in its open-chain form

Which are glucose, fructose, and galactose?

Which is galactose and glucose?

Name the monosaccharides

Name this disaccharide: Maltose, lactose or sucrose?

What are the two sugars that compose the disaccharide?

Name this disaccharide: Maltose, lactose or sucrose?

What are the two sugars that compose the disaccharide?

Name this disaccharide: Maltose, lactose or sucrose?

What are the two sugars that compose the disaccharide?

Alpha and beta configurations for monosaccharides:

Trans/opposite = alpha

Cis/same = beta

Amide v.s. Amine

Enamine v.s. Imine

KMnO₄

CrO₃

Oxidizing agents

Turn alcohols / aldehydes into carboxylic acids

O₃

Cleaves alkenes

LiAlH₄

NaBH₄

H₂ (gas) + Pd (catalyst)

Reduces aldehydes, ketones, and carboxylic acids to 1º alcohols

Converts amides and nitriles (CN) to amines

Label: acetal, ketal, hemiacetal, hemiketal

Which come from ketones, which come from aldehydes?

Tollen’s reagent:

Purpose

(Strong/weak?) (Oxidizing/reducing?) agent

Identifies aldehydes (by converting them into carboxylic acids)

Weak oxidizing agent?

All reducing sugars will give a (+)

Benedict’s reagent:

Purpose

(Strong/weak?) (Oxidizing/reducing?) agent

Identifies aldehydes (+ = red solution)

Weak oxidizing agent

All reducing sugars will give a (+)