New Crystalline Salts of Nicotinamide Riboside as Food Additives.

NR ⁺ is a highly effective vitamin B ₃ type supplement due to its unique ability to replenish NAD ⁺ levels. While NR ⁺ chloride is already on the market as a nutritional supplement, its synthesis is challenging, expensive, and low yielding, making it cumbersome for large-scale industrial production. Here we report the novel crystalline NR ⁺ salts, d/l/dl-hydrogen tartrate and d/l/dl-hydrogen malate. Their high-yielding, one-pot manufacture does not require specific equipment and is suitable for multi-ton scale production. These new NR ⁺ salts seem ideal for nutritional applications due to their bio-equivalence compared to the approved NR ⁺ chloride. In addition, the crystal structures of all stereoisomers of NR ⁺ hydrogen tartrate and NR ⁺ hydrogen malate and a comparison to the known NR ⁺ halogenides are presented.