Essential features for antioxidant capacity of ascorbic acid (vitamin C)

Area of Science:

• Biochemistry
• Theoretical Chemistry
• Medicinal Chemistry

Background:

• Vitamin C (ascorbic acid) is vital for human health, involved in collagen production and possessing antioxidant properties.
• Its precise cellular antioxidant mechanisms remain unclear, and no derivatives have been previously proposed.
• Theoretical studies on ascorbic acid's antioxidant and redox mechanisms exist, but lack derivative exploration.

Purpose of the Study:

• To perform an electronic study on the antioxidant capacity of ascorbic acid derivatives.
• To identify key functional groups responsible for ascorbic acid's antioxidant activity.
• To propose novel ascorbic acid derivatives with enhanced antioxidant potential.

Main Methods:

• Utilized theoretical chemistry at the Density Functional Theory (DFT)/B3LYP/6-311+(2d,2p) level of theory.
• Analyzed simplified and modified structures of ascorbic acid derivatives.
• Evaluated antioxidant capacity based on electronic properties and molecular characteristics.

Main Results:

• Enol hydroxyl groups, particularly the vicinal enolic hydroxyl on the β position, are crucial for antioxidant capacity.
• A keto-alkene derivative exhibited superior molecular characteristics compared to ascorbic acid.
• Lactone derivatives did not show enhanced antioxidant potential over ascorbic acid.

Conclusions:

• The study identified key structural features influencing ascorbic acid's antioxidant capacity.
• A keto-alkene derivative presents a promising lead for developing new antioxidants.
• Further research can explore novel ascorbic acid derivatives based on spin density and chemical stability insights.