Structure-activity relationships of quinazoline derivatives: dual-acting compounds with inhibitory activities toward both TNF-alpha production and T cell proliferation

Syntheses and Structure-Activity Relationships of N-Phenethyl-Quinazolin-4-yl-Amines as Potent Inhibitors of Cytochrome bd Oxidase in Mycobacterium tuberculosis

The development of cytochrome bd oxidase (cyt-bd) inhibitors are needed for comprehensive termination of energy production in Mycobacterium tuberculosis (Mtb) to treat tuberculosis infections. Herein, we report on the structure-activity-relationships (SAR) of 22 new N-phenethyl-quinazolin-4-yl-amines that target cyt-bd. Our focused set of compounds was synthesized and screened against three mycobacterial strains: Mycobacterium bovis BCG, Mycobacterium tuberculosis H37Rv and the clinical isolate Mycobacterium tuberculosis N0145 with and without the cytochrome bcc:aa ₃ inhibitor Q203 in an ATP depletion assay. Two compounds, 12a and 19a, were more active against all three strains than the naturally derived cyt-bd inhibitor aurachin D.

Synthesis and Spectral Characterization of 4,7-Dichloro-6-nitroquinazoline

Afatinib is a 4-anilinoquinazoline tyrosine kinase inhibitor (TKI) in the form of a dimaleate salt which is indicated for the treatment of locally advanced or metastatic non-small cell lung cancer (NSCLC). The most scalable route for the synthesis of this drug was reported in two Boehringer Ingelheim patents, in which the title compound, 4,7-dichloro-6-nitroquinazoline (IV), is an important intermediate. Compound IV is also present in a number of synthetic pathways for various 4,7-disubstituted quinazoline derivatives displaying high therapeutic potential. However, no detailed characterization of this popular compound has been reported, possibly due to its high instability. In this paper, IV was prepared in an overall yield of 56.1% by a 3-step process (condensation, nitration, and chlorination) from 2-amino-4-chlorobenzoic acid (I). The target compound has been for the first time fully characterized by melting point, mass-spectrometry, FT-IR, 1H-NMR and 13C-NMR spectroscopies.

Synthesis, molecular docking and biological potentials of new 2-(4-(2-chloroacetyl) piperazin-1-yl)-N-(2-(4-chlorophenyl)-4-oxoquinazolin-3(4H)-yl)acetamide derivatives

In the present study, a series of 2-(4-(2-chloroacetyl)piperazin-1-yl)-N-(2-(4-chlorophenyl)-4-oxoquinazolin-3(4H)-yl)acetamide derivatives was synthesized and its chemical structures were confirmed by physicochemical and spectral characteristics. The synthesized compounds were evaluated for their in vitro antimicrobial (tube dilution technique) and anticancer (MTT assay) activities along with molecular docking study by Schrodinger 2018-1, maestro v11.5. The antimicrobial results indicated that compounds 3, 8, 11 and 12 displayed the significant antimicrobial activity and comparable to the standards drugs (ciprofloxacin and fluconazole). The anticancer activity results indicated that compound 5 have good anticancer activity among the synthesized compounds but lower active than the standard drugs (5-fluorouracil and tomudex). Molecular docking study demonstrated that compounds 5 and 7 displayed the good docking score with better anticancer potency within the binding pocket and these compounds may be used as a lead for rational drug designing for the anticancer molecules.

Anti-arthritis effect of a novel quinazoline derivative through inhibiting production of TNF-α mediated by TNF-α converting enzyme in murine collagen-induced arthritis model

TNF-α is a dominant inflammatory mediator in the pathogenesis of inflammatory diseases including rheumatoid arthritis. In our research, we discovered 2-chloro-N-(4-(2-morpholinoethoxy)phenyl)quinazolin-4-amine (9c) exhibited an outstanding anti-inflammatory activity on inhibiting TNF-α production with an IC50 of 8.86 μM in RAW264.7 cells. Interestingly, 9c had no effect on mRNA level of TNF-α but up-regulated the precursor of TNF-α (pro-TNF-α). Then, we studied TNF-α converting enzyme (TACE), which is the most important proteases responsible for the release of TNF-α from pro-TNF-α to soluble TNF-α. The results showed 9c reduced TACE both on the levels of mRNA and protein in a dose-dependent manner. In vivo study, collagen-induced arthritis (CIA) mice were treated by 9c orally. 9c exhibited significant anti-arthritis effect by ameliorating arthritic score, reducing inflammatory cell infiltration, protecting joints from destruction and decreasing the production of systemic TNF-α, IL-6, IL-1β. The underlying mechanism of 9c on CIA was coincided with the in vitro, which was mediated by TACE. In conclusion, we discovered a novel quinazoline derivative which ameliorates arthritis through inhibiting production of TNF-α mediated by TACE for the first time.

Erlotinib and gefitinib, small-molecule EGFR inhibitors. New uses for old drugs?

The process of drug discovery and development takes decades and costs billions, therefore it is pertinent to consider the clinical ‘off-target’ actions of currently approved agents. The safety profile of these agents is already established and there is experience of specific clinical utility. The investigation of recognised ‘off-target’ actions may provide a more rapid avenue to address ‘non-target’ disease states. Herein the potential of the epidermal growth factor receptor inhibitors erlotinib and geritinib are considered within the context of diabetes.

Synthesis and evaluation of 6-nitro-7-(1-piperazino)quinazolines: dual-acting compounds with inhibitory activities toward both tumor necrosis factor-alpha (TNF-alpha) production and T cell proliferation

We investigated the chemical modifications of the nitroquinazoline derivative (1) through the replacement of the NH group at the C(4)-position with several N-alkyl groups to increase the lipophilicity at the C(4)-position. Among them, we found that the N-methyl analogue (5a) showed a 2-fold loss in the inhibitory activity toward tumor necrosis factor-alpha (TNF-alpha) production in vitro as compared with the NH analogue (1); however, 5a exhibited an oral inhibitory activity on TNF-alpha production with an ED50 value of 26 mg/kg, whereas 1 did not. Moreover, the oral bioavailability of 5a was higher than that of 1 (1, F=1%; 5a, F=21%), and the calculated ClogP value for 5a was higher than that for 1. These results suggest that the improved lipophilicity of 5a compared with that of 1 reflects its greater inhibitory activity on TNF-alpha production in vivo as well as oral bioavailability.

Structure-activity relationships of 6-nitroquinazolines: dual-acting compounds with inhibitory activities toward both TNF-alpha production and T cell proliferation

We synthesized various 6-nitroquinazolines by modifying the structure of compound 1 and evaluated their inhibitory activities toward both TNF-alpha production and T cell proliferation responses. The presence of the unsubstituted piperazine ring at the C(7)-position was required for both inhibitory activities. In this series of compounds, 5d and 5f, containing the 4-fluorophenyl and 3,4-difluorophenyl moiety, respectively, at the C(4)-position, showed the suppressing effects toward both responses with low cell growth inhibition. Furthermore, the oral administration of these compounds mentioned above at doses of 30 and 100 mg/kg also resulted in significant inhibition of TNF-alpha production induced by LPS in vivo.