The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Infrared absorption studies. XI. NH-H and NH-O bonds》. Authors are Buswell, A. M.; Downing, J. R.; Rodebush, W. H..The article about the compound:Ethyl 3,5-Dimethyl-2-pyrrolecarboxylatecas:2199-44-2,SMILESS:O=C(C1=C(C)C=C(C)N1)OCC).Related Products of 2199-44-2. Through the article, more information about this compound (cas:2199-44-2) is conveyed.
cf. C. A. 34, 4663.8. Data are given for the IR absorption of acetylglycine Et ester in solution and for the solid, for 3,5-dimethyl-2-carbethoxypyrrole in solution, for diphenylamine in CCl4 solution, for the solids and for mixtures of diphenylamine and dimethylacetamide and for solid films of acetamide, trichloroacetamide, n-valeramide, sulramic acid, glycine and diketopiperazine. These data indicate that intermol. NHN bonds show a fundamental IR absorption near 3 μ. These bonds are formed only when the first N is relatively much more acidic than the second N. NH-O bonds are formed only with a semipolar O. The bonding observed by IR studies in amides and the peptide linkage is believed to be NHO- with absorption near 3.0 μ if isolated but at 3.22 μ if the bonds are formed in pairs. A coplanar structure is postulated for the CONHR group which involves geometrical isomerism. This structure must be considered in any explanation of protein behavior.
As far as I know, this compound(2199-44-2)Related Products of 2199-44-2 can be applied in many ways, which is helpful for the development of experiments. Therefore many people are doing relevant researches.
Reference:
Thiazolidine – Wikipedia,
Thiazolidine – ScienceDirect.com