Fig. 1: Synthesis of curcumin-Na. | Nature Communications

Fig. 1: Synthesis of curcumin-Na.

From: Photoinhibiting via simultaneous photoabsorption and free-radical reaction for high-fidelity light-based bioprinting

Fig. 1

a Synthetic scheme of curcumin-Na (Cur-Na) using curcumin and sodium bicarbonate. The H+ of phenolic hydroxyl in curcumin molecular is substituted by Na+ (red ellipses), while the carbonyl bond in curcumin undergoes keto-enol tautomerism (blue ellipses). b 1H-NMR spectra of curcumin (upper blue) and Cur-Na (lower red), showing the representative changes of chemical shifts that occurred during the synthesis process. The blue-shaded area expresses the characteristic resonance of the phenolic hydroxyl group (δ = 9.65 ppm). The green shading is the alkene signal (δ = 5.93 ppm), indicating the formation of the C=C double bond.

Back to article page