New homobimetallic organotin(IV) dithiocarbamates as potent antileishmanial agents

Abstract

In the present study, di- and triorganotin(IV) dithiocarbamates, (n-Bu₂SnCl)₂L (1), (Ph₂SnCl)₂L (2), (Ph₃Sn)₂L (3), and (Bz₃Sn)₂L (4), have been synthesized, where L is 4,4-trimethylenedipiperidine-1-carbodithioate. The coordination mode of the ligand to Sn, structural confirmation and geometry assignment around Sn(IV), in solid and solution forms, were made using FT-IR, multinuclear NMR (¹H and ¹³C), and X-ray single crystal analysis. The latter technique confirms anisobidentate mode of chelation of the ligand with Sn, in 1–4, with distorted trigonal bipyramidal or square pyramidal geometry. Complexes 1–4 present supramolecular structures mediated by different C⋯H and Cl⋯H intermolecular interactions. These complexes maintain five-coordination even in solution, except for 4. The antileishmanial activity of all complexes are well above the standard drug, especially (Bz₃Sn)₂L. The Docking studies suggest that high antileishmanial action of (Bz₃Sn)₂L is due to its lowest binding energy with enzyme trypanothione synthetase. The antileishmanial activity of the complexes is promising enough that they may be used for antileishmanial treatment after further investigations.

Graphical Abstract

Four new homobimetallic organotin(IV) dithiocarbamates have been synthesized and characterized by different analytical techniques. These compounds have pronounced antileishmanial and antimicrobial activities.

Keywords:

• Homobimetallic
• Organotin
• Antileishmanial
• Supramolecular
• Dithiocarbamate

Additional information

Funding

Funding. We acknowledge the financial support of Higher Education Commission of Pakistan and Quaid-i-Azam University, Islamabad, Pakistan.