Synthesis and Characterization of New 1, 3, 4-Thiadiazoles Substituted with Imidazolidine Moiety

2-amino-5-mercapto-1, 3, 4-thiadiazolewas introduced in condensation reactions with both terephthaldehyde and 4-dimethylaminobenzaldehyde to yield imine derivatives1a and 1b respectively. The resulting imine1awas treated with amino acids L-valine and L-cysteine, also the imine 1b wasreacted with amino acids L-cysteine, L-isoleucine and L-tyrosine to obtain five new imidazolidine derivatives2a-erespectively.2-amino-5-mercapto-1, 3, 4-thiadiazolewas also converted to the corresponding azoaldehyde derivative3 through coupling reaction of its diazonium salt with 4-hydroxybenzaldehyde dissolved in sodium hydroxide solution. The resulting azoaldehyde 3 was reacted with2-amino-5-mercapto-1, 3, 4-thiadiazoleto give the corresponding azoimine derivative 4. Treatment of the resulting azoimine 4 with amino acids glycine, L-valine and L-cysteine afforded three new imidazolidine derivatives5a-crespectively.