3-Hydroxyflavone Explained

3-Hydroxyflavone is a chemical compound. It is the backbone of all flavonols, a type of flavonoid. It is a synthetic compound, which is not found naturally in plants. It serves as a model molecule as it possesses an excited-state intramolecular proton transfer (ESIPT) effect^[1] to serve as a fluorescent probe to study membranes for example^[2] or intermembrane proteins.^[3] The green tautomer emission (λ_max ≈ 524 nm) and blue-violet normal emission (λ_max ≈ 400 nm) originate from two different ground state populations of 3HF molecules.^[4] The phenomenon also exists in natural flavonols. Although 3-hydroxyflavone is almost insoluble in water, its aqueous solubility (hence bio-availability) can be increased by encapsulation in cyclodextrin cavities.^[5]

Synthesis

The Algar-Flynn-Oyamada reaction is a chemical reaction whereby a chalcone undergoes an oxidative cyclization to form a flavonol.

Notes and References

1. http://www.iop.org/EJ/abstract/1674-1056/17/4/052 All-optical switchings of 3-hydroxyflavone in different solvents. Wu Feng, Lin Lie, Li Xiang-Ping, Yu Ya-Xin, Zhang Gui-Lan and Chen Wen-Ju, Chinese Phys. B 17 1461-1466.
2. 10.1016/S1386-1425(96)01825-2 . 53 . 3. Excited state proton transfer fluorescence of 3-hydroxyflavone in model membranes . 1997 . Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy . 457–462 . Guharay . Jayanti . Chaudhuri . Rupali . Chakrabarti . Abhijit . Sengupta . Pradeep K.. 1997AcSpA..53..457G .
3. Chaudhuri. Sudip. Banerjee. Anwesha. Basu. Kaushik. Sengupta. Bidisa. Sengupta. Pradeep K.. 2007. Interaction of flavonoids with red blood cell membrane lipids and proteins: Antioxidant and antihemolytic effects. International Journal of Biological Macromolecules. 41. 1 . 42–48. 10.1016/j.ijbiomac.2006.12.003. 17239435.
4. 10.1016/0584-8539(95)01622-8 . 52 . 2. Effect of reverse micelles on the intramolecular excited state proton transfer (ESPT) and dual luminescence behaviour of 3-hydroxyflavone . 1996 . Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy . 275–278 . Sarkar . Munna . Guha Ray . Jayanti . Sengupta . Pradeep K.. 1996AcSpA..52..275S .
5. 10.1016/j.molstruc.2011.09.055 . 1006 . 1–3 . Encapsulation of 3-hydroxyflavone in γ-cyclodextrin nanocavities: Excited state proton transfer fluorescence and molecular docking studies . 2011 . Journal of Molecular Structure . 483–488 . Pahari . Biswapathik . Chakraborty . Sandipan . Sengupta . Pradeep K.. 2011JMoSt1006..483P .