The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Perylene and its derivatives. XLIX. The perylene trihalides of K. Brass and E. Clar》. Authors are Zinke, A.; Pongratz, A.; Scholtis, K.; Hanus, F..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).Name: Ethyl 3,5-Dimethyl-2-pyrrolecarboxylate. Through the article, more information about this compound (cas:2199-44-2) is conveyed.
cf. C. A. 30, 6362.7. It had been shown that Brass and Clar’s “”perylene tribromide”” (C. A. 27, 720) is not a substance of constant composition and that the primary product of the action of Br on perylene is rather a tetrabromide. In a reply, B. and C. (C. A. 30, 6735.3) lay stress on the constancy in composition of their tribromide and deplore the fact that Z. and P. give the results of only 1 of the numerous analyses of their Br product. To meet this criticism a number of further bomb determinations are reported, although the authors believe their earlier data suffice to establish their contention. B. and C. also doubt the constancy of the composition of the tetrabromide and believe the higher Br values obtained by Z. and P. are due to the fact that they did not remove the excess of Br at an elevated temperature Some determinations are now reported in which the excess Br was removed with a current of warm (50-60°) air; they, too, show distinctly that 4 atoms Br are first taken up. Repeated treatment of the product with warm air showed that the loss in weight is at first due almost exclusively to evaporation of the mechanically attached Br, and when this ceases to be given off the compound has the composition of a tetrabromide. Further loss of Br as HBr occurs at an appreciably slower rate; a preparation kept in a desiccator for hrs. still contained considerably more Br than the amount calculated for a tribromide. The substance prepared by the action of I on perylene in hot benzene according to the (very incomplete) directions of B. and C. likewise has not a constant composition and was always found to contain more I than that calculated for a triiodide; the I content of the beautifully crystalline product depended on the concentration and the total amount of I dissolved in the benzene.
There are many compounds similar to this compound(2199-44-2)Name: Ethyl 3,5-Dimethyl-2-pyrrolecarboxylate. if you want to know more, you can check out my other articles. I hope it will help you，maybe you’ll find some useful information.
Reference:
Thiazolidine – Wikipedia,
Thiazolidine – ScienceDirect.com