Rubrocurcumin is a red-colored dye that is formed by the reaction of curcumin and boric acid.

[1] The reaction of curcumin with borates in presence of oxalic acid produces rubrocurcumin.

Rubrocurcumin is a neutral molecule, while rosocyanine is ionic.

In rubrocurcumin, one molecule of curcumin is replaced with oxalate compared to rosocyanine.

Complexes with boron such as rubrocurcumin are called 1,3,2-dioxaborines.