Table 1 Activity of the naphthoquinones on bloodstream trypomastigotes of T. cruzi at 37°C

NQ1

1,4-Naphthoquinone

0.79 ± 0.02

NQ2

2-Methyl-1,4-naphthoquinone (menadione)

6.04 ± 0.35

NQ3

2-Hydroxy-1,4-naphthoquinone (lawsone)

563.18 ± 83.28

NQ4

2-Acetoxy-1,4-naphthoquinone

63.02 ± 5.8

NQ5

2-Bromo-1,4- naphthoquinone

1.37 ± 0.03

NQ6

2,3-Dichloro-1,4- naphthoquinone (dichlone)

2.17 ± 0.29

NQ7

5-Hydroxy-1,4-naphthoquinone (juglone)

6.51 ± 0.48

NQ8

5-Acetoxy-1,4- naphthoquinone

0.16 ± 0.01

NQ9

5-Methoxy-1,4-naphthoquinone

1.02 ± 0.29

NQ10

2-Bromo-5-hydroxy-1,4-naphthoquinone

2.15 ± 0.22

NQ11

2-Bromo-5-acetoxy-1,4-naphthoquinone

2.43 ± 0.50

NQ12

2-Bromo-5-methoxy-1,4-naphthoquinone

1.25 ± 0.26

NQ13

3-Bromo-5-hydroxy-1,4-naphthoquinone

2.52 ± 0.37

NQ14

3-Bromo-5-acetoxy-1,4-naphthoquinone

0.85 ± 0.08

NQ15

3-Bromo-5-methoxy-1,4-naphthoquinone

1.41 ± 0.15

NQ16

2-Methyl-5-hydroxy-1,4-naphthoquinone (plumbagin)

1.38 ± 0.26

Bz

Benznidazole

26.0 ± 4.0