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Number of chiral carbons In $ \beta -D-(+)$ glucose is

$\begin {array} {1 1} (A)\;6 & \quad (B)\;4 \\ (C)\;3 & \quad (D)\;5 \end {array}$

1 Answer

1. A chiral carbon has four different groups attached. $\alpha$ -D-Glucose has no plane of symmetry, so all the carbon atoms are different.
There are five chiral carbons:
2.Three hydroxyl groups are below the plane of the ring.
3. C-5 is attached to an oxygen within the ring and a carbon (C-6) outside the ring.
4.Three of the ring hydrogens (on C-1, C-2, and C-4) are above the plane of the ring, and two (on C-3 and C-5) are below the plane of the ring.
Hence D is the correct answer
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answered Mar 29, 2014 by thanvigandhi_1
edited Oct 23 by meena.p