Antileishmanial Activity of New Synthesized Schiff and Mannich (Morpholine) Base Compounds

Leishmaniasis is an important parasitic disease in many countries, including ours. A variety of drugs are currently used for its treatment. However, certain side effects of these drugs, such as teratogenicity, hepatotoxicity and nephrotoxicity, have been reported in some patients. The goal of this research is to determine the antileishmanial effects of eight different previously synthesised compounds containing Schiff and Mannich bases (morpholine) against Leishmania infantum (L. infantum) promastigotes by the liquid microdilution method utilising alamarBlue.

Compounds containing Schiff bases (a-d) and both Schiff bases and morpholine rings (e-h) were tested. Compounds were diluted in the range of 20000-39 μg/mL. L. infantum promastigotes were added to the wells, which were then incubated at 27 °C. The proliferation of Leishmania promastigotes was evaluated after 24, 48 and 72 hours.

In this study, compounds b, c and d (MIC values 156 μg/mL, 78 μg/mL and 156 μg/mL) were found to be effective against L. infantum promastigotes, whereas compound f (MIC >20000 μg/mL) was found to be more the most ineffective compound.

These compounds may be potential drug candidates for the treatment of leishmaniasis. According to the results, there is a need for further studies, such as in vivo experimental animal models and ex vivo Leishmania amastigote macrophage cultures for compounds showing antileishmanial effects.