Question

Draw the simple Fischer projection formulae of \[D - \left( + \right)\] glucose and \[D - \left( - \right)\] fructose.

Answer 1

Hint: Glucose and fructose are simple sugars of monosaccharides. The primary source of energy required for living organisms is glucose. Plants and algae prepare glucose during the process of photosynthesis with the help of water, sunlight and carbon dioxide.

Complete step by step answer:
Fructose is a simple ketonic monosaccharide. Basically monosaccharides are the fundamental units of carbohydrates that cannot be further reduced to simpler compounds whereas glucose is a simple sugar with six carbon atoms and one aldehyde group.
Firstly, we will discuss the structure of glucose.
Glucose can be called as aldohexose or dextrose. It is a monomer of many large compounds such as carbohydrates, starch and cellulose. Its molecular formula is ${C_6}{H_{12}}{O_6}$. Now, the configuration of D/L glucose was proved by the scientist Emil Fischer. He gave the following Fischer projections.

Now, let’s discuss fructose.
Fructose is a simple ketonic monosaccharide which is present in many plants. It is also known as fruit sugar. The fructose sugar is usually found in fruits, flowers, trees, honey, berries and n rooted vegetables. The structure of fructose is a shown:

It is basically a levorotatory monosaccharide because it rotates the plane polarized light in the left direction.

Note:
Fructose helps in enhancing the taste in food and beverages. High fructose corn syrup is also used as a sweetener in many cough suppressants and decongestant liquids whereas glucose is used in the treatment of hypoglycemia i.e. low blood sugar. It is also given to the patients who are very sick and cannot eat.