Synthesis, Characterization and Antifertility Activity of New Unsymmetrical Macrocyclic Complexes of Tin(II)

Kripa Sharma,S C Joshi,R V Singh

doi:10.1155/mbd.2000.237

Abstract

A new series of unsymmetrical macrocyclic complexes of tin(ll) has been prepared by the template process using bis(3-oxo-2-butylidene)propane-1,3-diamine as precursor. This affords a method to synthesize these complexes with various ring sizes. The tetradentate macrocyclic precursor [N4mL] reacts with SnCl2 and different diamines in a 1:1:1 molar ratio in refluxing methanol to give complexes of the type [Sn(N4mL)Cl2]. The ring expansion has been achieved by varying the diamine between the two diacetyl amino nitrogen atoms. The macrocyclic precursor and its metal complexes have been characterized on the basis of elemental analysis, molar conductance, molecular weight determinations, IR, 1H NMR,13C NMR, 119Sn NMR and electronic spectral studies. An octahedral geometry around the metal ion is suggested for these complexes. On the basis of molecular weights and conductivity measurements, their monomeric and non-electrolytic nature has been confirmed. The precursor and complexes have been screened in vitro against a number of pathogenic fungi and bacteria to assess their growth inhibiting potential. The testicular sperm density and testicular sperm morphology, sperm motility, density of cauda epididymal spermatozoa and fertility in mating trails and biochemicals parameters of reproductive organs have been examined and discussed.

Highlights

The coordination chemistry of macrocyclic precursors is a fascinating area which has attracted the attention of inorganic chemists
Nowadays interest is focussed on the synthesis of macrocyclic complexes with potential medicinal applications, as contrast-enhancing agents in magnetic resonance imaging (MRI)9’1 as n.m.r, shift and relaxation reagentsl’ and as RNA cleavage catalyst13’14
The biochemist[18] of synthetic organometallic has generated active research relating to their biochemical significance The importance of metal-nitrogen bonding and their prominence in agricultural, medicinal and industrial chemistry led us to synthesize and screen the precursors and their macrocyc|ic compounds for their antifungal, antibacterial and antifertility activities

Summary

MATERIALS AND METHODS

All reagents were obtained commercially and by standard procedures. The reactions were carried out under strictly anhydrous conditions. The reaction was carried out in 2:1 molar ratio heated under reflux for 12 hours. The reaction mixture was cooled and the reddish brown compound obtained was recrystallised from ethanol (Yield 75%). The reaction mixture containing bis(3-oxo-2-butylidene)propane-l,3-diamine, diamine and tin chloride in 1"1"1 ratio in methanol was heated under reflux for 36 hours. The reaction mixture was cooled, transferred to an evaporating dish and set aside for a few hours, whereupon a dark coloured compound separated out. The product formed was washed and dried under reduced pressure, which was recrystallised from a 1:1 mixture of toluene and n-hexane in 78% yield.

Analytical Methods and Physical Measurements

RESULTS AND DISCUSSION

H NMR Spectra

C H18N202