TABLE 1

EC50 values of curcumin and its analogs against wild-type trypanosomes (Lister s427) and the stain adapted to AS-HK014 (TA014)

All values are average and S.E.M. of at least three independent determinations, with EC50 values against the two strains determined in parallel. Also shown is the resistance factor, which is the ratio EC50 TA014/EC50 s427. When more than one linker structure is given, it represents a mixture of both isomers. Significance was determined using a paired Student’s t test. Some of the HEK EC50 values listed here were previously reported by Changtam et al. (2010a).

Embedded Image
Compounds427 EC50TA014 EC50Resistance Factort TestR1R2R3R4HEK EC50SILinker Structure
µMµM
Curcumin2.7 ± 0.42.9 ± 0.131.06NSOCH3OHOCH3OH37.1 ± 6.313.7Embedded Image
AS-HK0140.11 ± 0.013.1 ± 0.128.2P < 0.001OCH3OHOCH3OH24.3 ± 2.4221Embedded Image
AS-HK0153.8 ± 0.124.1 ± 0.191.08NSOCH3OHOCH3OH75.6 ± 3.019.9Embedded Image
AS-HK0160.21 ± 0.0070.17 ± 0.0130.81NSOCH3OHOCH3OH8.1 ± 1.038.8Embedded Image
AS-HK0171.07 ± 0.041.04 ± 0.020.97NSOCH3OHOCH3OH22.0 ± 0.1420.6Embedded Image
AS-HK0180.18 ± 0.0080.84 ± 0.084.7P < 0.01OCH3OHOCH3OCH319.7 ± 1.6109Embedded Image
AS-HK0281.15 ± 0.071.08 ± 0.020.94NSOCH3OHOCH3OBz93.7 ± 11.281.5Embedded Image
AS-HK0330.80 ± 0.0050.73 ± 0.060.92NSOCH3OHOHOH36.3 ± 3.645.4Embedded Image
AS-HK0730.41 ± 0.030.45 ± 0.031.1NSOCH3OCH3OCH3OCH3202 ± 54493Embedded Image
AS-HK0850.52 ± 0.030.47 ± 0.040.9NSOCH3OHOHOH132 ± 19255Embedded Image
AS-HK0930.079 ± 0.0060.40 ± 0.015.2P < 0.001OCH3OCH2CNOCH3OCH2CN21 ± 2.3270Embedded Image
AS-HK0960.047 ± 0.0020.24 ± 0.045.1P < 0.001OCH3OAcOCH3OAc29.9 ± 1.8637Embedded Image
AS-HK0970.090 ± 0.0010.47 ± 0.025.2P < 0.001OCH3OHOCH3OAc24.8 ± 0.8275Embedded Image
AS-HK1180.44 ± 0.0190.43 ± 0.0051NSOCH3OHOCH3OC5H10Br17.1 ± 0.638.8Embedded Image
Diminazene0.13 ± 0.030.15 ± 0.041.15NS
Pentamidine0.005 ± 0.0010.003 ± 0.0010.6NS
Eflornithine39.5 ± 3.7643.17 ± 3.641.1NS
Cymelarsan0.0059 ± 0.00150.0078 ± 0.00211.33NS
Nifurtimox9.27 ± 1.097.21 ± 1.380.78NS
Suramin0.025 ± 0.0050.036 ± 0.0061.44NS
  • HEK, human embryonic kidney; NS, not significant; OBz, benzoyl; SI, selectivity index being the ratio of the EC50 values against HEK cells and wild-type trypanosomes.