Pini, J. J. P. B. published the artcileDegranulation of rat mesentery mast cells by antihistamines: influence of ionization, Application In Synthesis of 2508-72-7, the publication is Agents and Actions (1978), 8(5), 491-6, database is CAplus and MEDLINE.
Classical antihistamines were potent rat mast cell degranulators active in the range of 0.1 to 2.0 mM at pH 8.4. No relation between their potency as mast cell degranulators and their chem. structure or their activity as inhibitors of peripheral H1 histamine receptors could be established. Halogenation of diphenhydramine-HCl [147-24-0] and cyclizine-HCl [303-25-3], but not of promethazine [60-87-7], increased their activity. The alkylamino side chain of phenothiazine does not seem to be essential for degranulation since toluidine blue [92-31-9] and methylene blue [61-73-4], which lack it, were also active. Thionin [581-64-6], whose amino groups in the phenothiazine ring are not methylated, was inactive. The action of antihistamines on mast cells increased with an increase of pH, suggesting that activity can mainly be attributed to the uncharged base. However, the ionized mol. must be active at lower pH too. Above certain concentrations, antihistamines became inactive both at pH 7.0 and 8.4. At these higher concentrations, promethazine inhibited degranulation induced by chlorcyclizine or compound 48/80, an action not reversed by glucose. Thus, mast cell degranulation by antihistamines does not seem to be caused by the ionized base acting inside the cell following penetration of the cell membrane by the lipid soluble uncharged mol.
Agents and Actions published new progress about 2508-72-7. 2508-72-7 belongs to imidazoles-derivatives, auxiliary class Inhibitor,Immunology/Inflammation,Histamine Receptor, name is N-Benzyl-N-((4,5-dihydro-1H-imidazol-2-yl)methyl)aniline hydrochloride, and the molecular formula is C17H20ClN3, Application In Synthesis of 2508-72-7.
Referemce:
https://en.wikipedia.org/wiki/Imidazole,
Imidazole | C3H4N2 – PubChem