Synthesis of 4-substituted ethers of benzophenone and their antileishmanial activities

Leishmaniasis is a vector-borne protozoan disease; it mainly originates from the bite of sandfly and initiated when parasite is transmitted to human at metacyclic flagellated promastigote form. In the current study, a synthesis of a series of 4-substituted benzophenone ethers 1–20 was carried out in good yields and their in vitro antileishmanial activities were also screened. Among synthetic derivatives, 15 compounds 1, 3, 5–12, 15 and 17–20 showed antileishmanial activities against promastigotes of Leishmania major with IC50 values in the range of 1.19–82.30 µg ml−1, and the values were compared with those of the standard pentamidine (IC50 = 5.09 ± 0.09 µg ml−1). Our study identified a series of new antileishmanial molecules as potential leads. Structures of these synthetic compounds were deduced by different spectroscopic techniques, such as 1H and 13C nuclear magnetic resonance, electron impact and high-resolution electron impact mass spectrometry and IR.