Antiinflammatory activity of 5,6-diaryl-2,3-dihydroimidazo[2,1-b]thiazoles. Isomeric 4-pyridyl and 4-substituted phenyl derivatives.
Isomeric 5(6)-(4-pyridyl)- and 6(5)-(4-substituted-phenyl)-2,3-dihydroimidazo[2,1-b]thiazoles were prepared by a mixed benzoin-imidazothione route, and their structures were assigned by spectral comparison to compounds of established substitution pattern. The structural assignment was confirmed by X-ray analysis. Examination of the compounds for antiinflammatory activity by an adjuvant arthritic rat assay revealed strikingly higher potencies for one analogous series than for their isomers. This selectivity was paralleled in the ability to stimulate cell-mediated immunity, as reflected in an oxazolone-induced contact sensitivity model. A drug-receptor complex is proposed that requires at least three sites of interactions.
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000138:chemical synthesis*; D001169:Arthritis, Experimental / Q000188:drug therapy; D004353:Drug Evaluation, Preclinical; D007093:Imidazoles / Q000138:chemical synthesis* / Q000627:therapeutic use; D007202:Indicators and Reagents; D007536:Isomerism; D008958:Models, Molecular; D051381:Rats; D013329:Structure-Activity Relationship; D013844:Thiazoles / Q000138:chemical synthesis* / Q000627:therapeutic use; D014961:X-Ray Diffraction
D000893:Anti-Inflammatory Agents; D007093:Imidazoles; D007202:Indicators and Reagents; D013844:Thiazoles