Table 4.

The ABTS scavenging ability (%) of derivatives 5a–k

Compound	Scavenging ability (%)	Compound	Scavenging ability (%)
5a a	20.65 ± 0.26	5g a	23.83 ± 0.43
5b b	70.20 ± 0.11	5h a	22.09 ± 0.23
5c a	62.74 ± 0.48	5i a	66.30 ± 0.32
5d c	57.39 ± 0.32	5j a	26.30 ± 0.31
5e a	27.21 ± 0.12	5k a	76.16 ± 0.45
5f a	29.21 ± 0.27
Theophylline a	25.97 ± 0.27	Vitamin C d	78.42 ± 0.40

^a1 mg/mL; ^b 0.5 mg/mL; ^c 0.25 mg/mL; ^d 0.004 mg/mL; Data are mean ± SD (n = 3, p < 0.05)