JEE Main · 2020 · 04 Sep 2020 · Shift 2 · Biomolecules

The number of chiral centres present in threonine is ____ .

Answer: 2

Solution

Threonine,

C H_{3} - CH (OH) - CH (N H_{2}) - COOH

, has two carbons that each carry four different groups: the carbon bearing the

- N H_{2}

and

- COOH

groups, and the carbon bearing the

- OH

and

- C H_{3}

groups. It therefore has

2

chiral centres.

JEE Main · 2020 · 04 Sep 2020 · Shift 2 · Integer answer

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