Synthesis of some new 5-arylidene-2,4-thiazolidinedione esters

Abstract

Compounds containing the 1,3-thiazolidine-2,4-dione scaffold are gaining increasing scientific interest as potential interventional agents for a variety of disease states. A four-step synthesis of ethyl-(2-(5-arylidine-2,4dioxothiazolidin-3-yl)acetyl)glycinates, alaninates, butanoates, valinates and norvalinates is described. The synthesis began by converting 1,3-thiazolidine-2,4-dione into its potassium salt, which was treated with ethyl (2-chloroacetamido)glycinates, alaninates, butanoates, valinates and norvalinates, respectively, to obtain the penultimate products. These products were then subjected to a Knoevenagel condensation reaction with different aldehydes to obtain the desired products in low to excellent yields.

Synthesis of new 5-benzylidene-hydantoin esters

“…Concurrently, compounds 9a-d were synthesized by first protecting the amino acids with thionyl chloride in the presence of ethanol 12 or methanol 14 and subsequently reacting the intermediates with bromoacetyl chloride in the presence of potassium carbonate to afford compounds 9a-d in good yields. Finally, substitution reactions between benzylidenehydantoins 8 and compounds 9 followed by crystallization from acetone afforded the targeted ethyl or methyl [2-(5-benzylidene)-2,4-dioxoimidazolidin-3-yl] acetyl esters 10a-o in low to moderate yields (Figure 4).…”

“…These compounds were synthesized from their respective amino esters as described by Tshiluka et al 12 or Barman et al 14…”

“…These compounds were synthesized from their respective amino esters as described by Tshiluka et al 12 or Barman et al 14 General procedure for the synthesis of ethyl or methyl 2-(2,4-dioxoimidazolidin-…”

“…Many more hydantoin-containing compounds, both naturally occurring and synthetic, have been reported in reviews. 10,11 Encouraged by the results obtained in our previous study with 2,4-thiazolidinedione (Figure 3) in the synthesis of 5-benzylidene-2,4-thiazolidinedione esters, 12 we sought to expand this study by replacing a 2,4-thiazolidinedione moiety with a hydantoin moiety for the synthesis of new 5-benzylidene hydantoin esters (Scheme 1).…”