Skip to main content

Table 4 IC 50 for DPPH and ABTS radical scavenging ability of hydrazinyl thiazolyl coumarins 10 and comparison with known antioxidants BHT and quercetin

From: Microwave-assisted synthesis and antioxidant properties of hydrazinyl thiazolyl coumarin derivatives

Entry Compound R1 R2 R3 R4 DPPH assay IC50/μM ABTS assay IC50/μM
1 10a OH H H H 26 ± 0.96 32 ± 3.06
2 10b H OH H H 47 ± 1.24 53 ± 2.74
3 10c H H OH H 28 ± 0.62 41 ± 3.95
4 10d OH H OH H 24 ± 0.67 29 ± 1.88
5 10e OH H H Br 16 ± 0.82 19 ± 2.76
6 10f OH OMe H H 30 ± 0.78 36 ± 3.18
7 10g H - - - 85 ± 0.66 78 ± 5.64
8 10h OH - - - 22 ± 1.75 32 ± 3.42
9 BHT - - - - 71 ± 0.82 -
10 quercetin - - - - 18 ± 0.99 20 ± 2.19
11 Trolox - - - - - 112 ± 4.29
  1. Required concentration of the tested compound to scavenge 50% of the DPPH radical present at a concentration of 0.1 mM; average from 3 assays. Required concentration of the tested compound to scavenge 50% of the ABTS radical present at a concentration of 0.12 mM; average from 3 assays.