How do you identify Fischer projections?

To find the enantiomer of a molecule drawn as a Fischer projection, simply exchange the right and left horizontal bonds. To determine whether the molecule in Fischer projection is a meso compound, draw a horizontal line through the center of the molecule and determine whether the molecule is symmetric about that line.

Are Fischer projections chiral?

Every cross on a Fischer projection is a chiral center. Fischer projections are convenient for comparing the stereochemistries of molecules that have many chiral centers. But these projections have their own sets of rules and conventions for how you can rotate and move them.

How to draw the Fischer projection for an amino acid?

The general formula for an amino acid is RCH(NH₂)COOH. In cysteine, R = CH₂SH. You draw the Fischer projection for an amino acid in the same way as for a carbohydrate. The main chain is vertical, with C-1 at the top.

How many Fischer projections can you draw for lactic acid?

Thus, the maximum number of Fischer projections that can be drawn to represent ( R )-lactic acid is twelve. 2. Use the following stepwise procedure to generate the twelve Fischer projections that represent ( R )-lactic acid. Step 1: Draw four Fischer projection skeletons.

Is the Fischer projection 1 and 2 the same molecule?

Therefore, 1 and 2 must represent the same molecule. The two chiral centers in each of these two Fischer projections bear the same ligands: H atom, OH group, CO 2 H group, and CH (OH)CO 2 H group. However, in this case, it is obvious that the corresponding chiral centers do not have the same absolute configurations.

What is the bond skeleton of a Fischer projection?

Using the factorials, the answer is 4! = 1 x 2 x 3 x 4 = 24. Let us now consider lactic acid. The lactic acid molecule has one chiral center. Therefore, a Fischer projection representing either enantiomer of lactic acid has the following bond skeleton around the chiral center.