Side chain polarity Reset Display the side chain carboxyl group as Ball & Stick. Some facts on L-aspartic acid. Abbreviation: Asp. One-letter code: D, (near A). Molecular mass: 133 daltons. Side chain (or R-group) features: Structural formula: Formula: -CH2-COO-; Category: polar; acidic. pKa: 3.9. Return to image of Asp.
Some facts on L-aspartic acid.