Question

Identify the Haworth formula of \(\beta\) - D (+) Glucopyranose.

• A.

  

• B.

  

• C.

  

• D.

  

Hint:

In beta-D-glucose all substituents on the ring are equatorial: CH2OH up, OH at C1 up, C2 down, C3 up, C4 down.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept
\(\beta\)-D-glucopyranose is a six-membered ring in which the anomeric \(-\text{OH}\) on \(\text{C-1}\) is on the same side as the \(-\text{CH}_{2}\text{OH}\) group (for D-sugars, upwards).

Step 2: Positions in the Haworth ring
D-glucose: \(-\text{OH}\) on \(\text{C-2}\) down, on \(\text{C-3}\) up, on \(\text{C-4}\) down, and \(-\text{CH}_{2}\text{OH}\) up on \(\text{C-5}\).

Step 3: Beta configuration
For the \(\beta\)-anomer, \(\text{C-1}\) has \(-\text{OH}\) up and H down.

Step 4: Match the figures
The first option has C1 OH up, C2 OH down, C3 OH up, C4 OH down and CH2OH up, so it is the beta form. The second has C1 OH down, which is the alpha form. The last two are open-chain (Fischer-type) drawings.

Final Answer:
The first option shows beta-D-glucopyranose. \[ \boxed{\text{(A) }\text{Haworth ring with C-1 OH up and CH}_{2}\text{OH up}} \]