Reactions with 4-thiohydations, synthesis of imidazothiazolone derivations their reactions towards aromatic aldehydes, aryldiazonium salts and mannich reaction

5-A RYLAZO-l-phenyl-4-thiohydantoins [la-f] reacted with chlorxroacetic acid to give the corresponding 4-carboxymethyl mercapto derivatives [IIa-f]. IIa was hydrolysed with a mixture of ethanol hydrochloric acid to give 5-phenylazo-l-phenyl-hydantoin [III] Cyclisation of IIa-e with acetic anhydride afforded imidazothiazol one derivatives IVa-e. Condensation of IVa, d with aldehydes gave the arylidene derivatives [Va-c] and coupling with diazonium salts gave azo derivatives [Vla-j]. IVa, d reacted with formaldehyde and the appropriate amine in ethyl alcohol to give the corresponding Mannich bases VIIa-f

Reactions with 4,5-diphenyl 2-mercaptoimidazole: synthesis of 2-substituted thiazolo [3,2-a] imidazoles

The potassium salt of 4,5-diphenyl-2-mercaptoimidazole [I] was reacted with 3-chloro-2,4-pentaneaione to give the S-alkyl derivative II. Compound II coupled with arenediazonium salts to give the azo derivatives [III]. On heating II and III with poly-phosphoric acid, cyclization took place and 2-substituted thiazolo [3,2-a] imidazoles V and VI were obtained. V Condensed with aromatic aldehydes to yield the cinnamoyl derivatives VII, which reacted with phenylhydrazine and hydroxylamine to give 2-pyr-azolinyl-and 2-isoxazolinyl-thiazolo [3,2-a] imidazole derivatives IX and X respectively