Inhibition of FcεRI-Mediated Activation of Mast Cells by 2,3,4-Trihydropyrimidino[2,1-a]isoquinolines

Abstract

Assays based on reporter gene technology represent today an important tool in the pharmaceutical industry for discovering novel compound classes interfering with the activation and signaling of target cells after stimulation. Here we describe a reporter gene assay targeting mast cell activation of IgE plus antigen, established in an attempt to identify substances preventing type I allergy (allergic rhinitis, allergic conjunctivitis, allergic asthma, and acute and chronic urticaria). The assay is based on a murine mast cell line designated CPII, stimulation by IgE plus antigen, and a reporter gene construct with the TNF alpha promoter linked to luciferase as a read-out system. Via screening about 50,000 substances, compound 2 was found to inhibit the reporter gene induction in the submicromolar range in this assay. Analogues of compound 2 of the 2,3,4-trihydropyrimidino[2,1-a]isoquinoline type were synthesized starting from 2-alkyl-substituted benzonitriles via aminolysis with 1,3-diaminopropane, dimetalation of 2-substituted 2-phenyl-1,4,5,6-tetrahydropyrimidines with n- and sec-butylithium, reaction with carboxylic acid methyl esters, and finally acidic dehydration. From about 50 derivatives, compound 41 was selected as a lead structure with an IC50 of 0.2 microM and a TC50 of 2.7 microM. In a first profiling in secondary assays, it effectively interfered with the production of mediators such as TNF alpha, IL-4, IL-6, IL-13, and leukotriene synthesis as measured by the corresponding ELISAs. In addition, a passive cutaneous anaphylaxis in mice (a typical type I reaction) is inhibited to more than 90% by compound 41, when administered intradermally 90 min before challenge.

A novel anti-inflammatory drug, SDZ ASM 981, for the treatment of skin diseases: in vitro pharmacology

“…Compounds SDZ ASM 981, 33-epi-chloro-33-desoxy-ascomycin, 4 empirical formula C 43 H 68 C1NO 11 , molecular weight 810´48, was synthesized from ascomycin. It is a colourless solid compound with a melting point of 134±138 8C and can be stored at room temperature.…”

“…The latter comprises an ideal surrogate parameter for measuring the induction of TNF-a in this cell type, They were cultured as recently described. 11 In each assay 4´10 4 clone 12 cells/well were used in 50 mL Tyrode-buffer/BSA. DC18 clone 10 cells are a genetically modi®ed subline of the murine dendritic cell line DC18; they also harbour a hTNF-a-luciferase TNF-a 3 H construct stably integrated into their genome.…”

Characterization of CDw92 as a Member of the Choline Transporter-Like Protein Family Regulated Specifically on Dendritic Cells

“…To test this, we ectopically expressed CDw92 in the murine mast cell CPII that was stably transfected with a TNF-␣ reporter gene (18), and we analyzed whether incubation by mAbs VIM15 or VIM15b inhibits IgE-mediated activation of this gene in these cells. Application of the mAbs neither cross-linked (using rabbit anti mouse Ig F(abЈ) 2 ) nor in monomeric form led to a significant inhibition of the Fc⑀RI-dependent transcriptional induction of TNF-␣ compared with an isotype control mAb.…”

AgI‐Catalyzed Cascade Strategy: Regioselective Access to Diversely Substituted Fused Benzimidazo[2,1‐a]isoquinolines, Naphthyridines, Thienopyridines, and Quinoxalines in Water

“…As a privileged fragment, isoquinolines are present in a variety of natural products and in numerous pharmaceutically important compounds such as the antitumor agent carcristine A4b (Figure 1). 4 Isoquinoline‐fused benzimidazoles have attracted considerable attention due to their immense and outstanding biological activities, such as anti‐HIV‐1, anticancer, antimicrobial, and antifungal properties 5a–5d.…”