| Penulis/Author |
Prof. Drs. Jumina, Ph.D. (1) ; YEHEZKIEL STEVEN KURNIAWAN (2); RATNA SARI (3); SRI NESSY HANDAYANI BR PURBA (4); Drs. Priatmoko, M.S. (5); Dr. Deni Pranowo, S.Si., M.Si. (6); Prof. Drs. Bambang Purwono, M.Sc., Ph.D. (7); JEFFRY JULIANUS (8); Prof. Dr. Drs. Abdul Karim Zulkarnain, M.Si., Apt. (9); Prof Dr.dr. Eti Nurwening Sholikhah, M.Kes. (10) |
| Abstrak/Abstract |
In the present work, a successful synthesis and high antioxidant
activity of C-alkylcalix[4]resorcinarene and C-alkylcalix[4]pyrogallolarene
derivatives were reported. The C-alkylcalix[4]resorcinarenes were prepared
from a cyclization reaction of resorcinol and either pentanaldehyde or
octanaldehyde under acidic conditions. Meanwhile, the Calkylcalix[4]pyrogallolarenes were prepared from a cyclization reaction of
pyrogallol with pentanaldehyde or octanaldehyde. Four synthesized
products, i.e., nBu-CR, nHep-CR, nBu-CP, and nHep-CP, were successfully
prepared in 92.4-96.4% yield. Their chemical structure was elucidated by
Fourier transform infrared (FTIR), liquid chromatography-mass
spectrometry (LC-MS), and proton nuclear magnetic resonance (1H-NMR)
analysis. The antioxidant activity assay of these compounds was evaluated
through an in vitro assay employing 2,2-diphenyl-1-picrylhydrazyl (DPPH)
radicals. The DPPH assay showed that the half-maximal inhibitory
concentration (IC50) values of nBu-CR, nHep-CR, nBu-CP, and nHep-CP
compounds were 25.1, 22.9, 11.5, and 21.9 µg mL-1, respectively. The IC50
value of the synthesized compounds was 2.0-4.3 times lower than the
positive standard of butylated hydroxytoluene (BHT, IC50 = 49.9 µg mL-1),
which was remarkable. This finding demonstrates that both Calkylcalix[4]resorcinarenes and C-alkylcalix[4]pyrogallolarenes are better
antioxidant agents than BHT. The nHep-CR compound was found as the best
antioxidant agent among the other compounds due to weaker intramolecular
and intermolecular hydrogen bondings and a longer alkyl chain. |
