C₂₀H₂₄N₁₀O₁₂P₂; MW 658.4 (free acid); λ_max 259 nm; ε 27000; sodium salt; purity > 95% HPLC. c-diAMP was identified as a second messenger that signals DNA integrity in Bacillus subtilis during sporulation, and is considered to be an additional purine-based signalling nucleotide with a more general function in prokaryotes. Detailed technical information available. References: Witte et al., Mol. Cell, 30, 167 - 178 (2008), Simm et al., J. Bacteriol., 189, 3613 - 3623 (2007). The structurally related bacterial second messenger c-diGMP (Cat. No. C 057) is offered as well.