The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Analysis of mixed preparations. II. Determination of antihistaminics in the mixed preparations》. Authors are Itai, Takanobu; Kamiya, Shozo.The article about the compound:Sodium 4-butyl-3,5-dioxo-1,2-diphenylpyrazolidin-4-idecas:129-18-0,SMILESS:O=C(N(C1=CC=CC=C1)N2C3=CC=CC=C3)[C-](CCCC)C2=O.[Na+]).HPLC of Formula: 129-18-0. Through the article, more information about this compound (cas:129-18-0) is conveyed.
cf. C.A. 51, 12433f. Antihistaminics, contained in the preparations for colds with various other ingredients, can be determined colorimetrically by precipitation as reineckates. By regulating the pH of their solutions or changing the quantity of added MeOH, the differential determination from other basic ingredients is accomplished. For the determination of antihistaminics in the mixture of aspirin, phenacetin, and caffeine, samples are dissolved in water and the antihistamine is precipitated with 2% NH4 reineckate in MeOH solution In the presence of aminopyrine or antipyrine, Clark-Lubs’ buffer solution is added in order to hold the pH of the solution at 6.5-7.0, then NH4 reineckate is added. The reineckate of ephedrine or methylephedrine is more soluble in MeOH than that of antihistaminics. From preparations containing thiamine, free antihistamine base is extracted with Et2O after adding K2HPO4. The aqueous solution hereby obtained is used for the determination of thiamine as its reineckate. Antihistaminics in the mixture of aspirin, phenacetin, and caffeine are titrated as free bases by passing through a column of Amberlite IR-4B (OH form). As aspirin is adsorbed on the resin, it is eluted with 50% alc. solution of N HCl, and titrated by bromometry.
The article 《Analysis of mixed preparations. II. Determination of antihistaminics in the mixed preparations》 also mentions many details about this compound(129-18-0)HPLC of Formula: 129-18-0, you can pay attention to it, because details determine success or failure
Reference:
Benzofuran – Wikipedia,
Benzofuran | C8H6O – PubChem