Green Chemical Synthesis and Analgesic Activity of Fluorinated Thiazolidinone, Pyrazolidinone, and Dioxanedione Derivatives

Table 1

Synthesis of 5-benzylidene-2-thioxo-1,3-thiazolidin-4-one 3a under different catalysts.

Entry	Catalyst	Solvent/temperature (°C)	Time (hrs)	Yield (%)
1	Boric acid	H2O/80	5	67
2	Oxalic acid	H2O/80	5	72
3	Alum	H2O/80	3	82
4	Lemon juice	H2O/80	3	84