Synthesis and Antioxidant Activity of Polyhydroxylated trans-Restricted 2-Arylcinnamic Acids

Molecules

Mitko Miliovsky¹  Ivan Svinyarov¹  Elena Prokopova²  Daniela Batovska²  Simeon Stoyanov²  Milen G. Bogdanov¹ 

[1] Faculty of Chemistry and Pharmacy, University of Sofia “St. Kliment. Ohridski”, 1, James Bourchier Blvd., Sofia 1164, Bulgaria; E-Mails:;Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Science, Acad. G. Bonchev Str. Bl. 9, Sofia 1113, Bulgaria; E-Mails:

关键词: homophthalic anhydride;    ROS;    antioxidants;    phenolic acids;    hybrid molecules;    synergy;   

DOI  :  10.3390/molecules20022555

来源: mdpi

【 摘 要 】

A series of sixteen polyhydroxylated trans-restricted 2-arylcinnamic acid analogues 3a–p were synthesized through a one-pot reaction between homophthalic anhydrides and various aromatic aldehydes, followed by treatment with BBr₃. The structure of the newly synthesized compounds was confirmed by spectroscopic methods and the configuration around the double bond was unequivocally estimated by means of gated decoupling ¹³C-NMR spectra. It was shown that the trans-cinnamic acid fragment incorporated into the target compounds’ structure ensures the cis-configuration of the stilbene backbone and prevents further isomerization along the carbon–carbon double bond. The antioxidant activity of compounds 3a–p was measured against 1,1-diphenyl-2-picrylhydrazyl (DPPH^●), hydroxyl (OH^●) and superoxide (O₂^●▬) radicals. The results obtained showed that the tested compounds possess higher activities than natural antioxidants such as protocatechuic acid, caffeic acid and gallic acid. Moreover, it was shown that a combination of two different and independently acting fragments of well-known pharmacological profiles into one covalently bonded hybrid molecule evoke a synergistic effect resulting in higher than expected activity. To rationalize the apparent antioxidant activity and to establish the mechanism of action, a SAR analysis and DFT quantum chemical computations were also performed.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.