Synthesis and evaluation of a novel series of quinoline derivatives with immunosuppressive activity

Recent advances in research of natural and synthetic bioactive quinolines

Many natural products that consist of quinoline core are found to be bioactive and the versatility of quinoline and its derivatives have attracted great attention in the field of drug development. As a result, in recent years, many green and sustainable synthetic approaches for the synthesis of structurally diverse quinolines have been developed. This review covers four main aspects, namely bioactive quinoline alkaloids, the biological activity and mechanism of action of quinoline-based compounds as well as various quinoline syntheses.

Nickel nanoparticles: a highly efficient and retrievable catalyst for the solventless Friedlander annulation of quinolines and their in silico molecular docking studies as histone deacetylase inhibitors

Highly efficient, solvent-free protocol for the synthesis of polysubstituted quinolines via Friedlander annulation using nickel nanoparticles from Aegle Marmelos Correa aqueous leaf extract.

Ultrasound-promoted synthesis and immunosuppressive activity of novel quinazoline derivatives

An environmentally friendly and mild Bischler cyclization was developed to access quinazolines with diverse substitution. Based on this method, a library of 53 quinazoline derivatives was prepared and tested in vitro for cytotoxicity and inhibition on T-cell and B-cell proliferation. Compounds 6b, 7b, 17b, 33, and 35 showed higher inhibitory activity on both T-cell and B-cell proliferations, with IC(50) values of 6.16, 6.30, 5.43, 2.54, and 9.80 μM on T-cell, respectively. All the tested compounds showed no obvious cytotoxicity at 10 μM concentration. The preliminary structure-activity relationship was concluded revealing that 4-position is the key modification site for potent quinazoline immunosuppressive agent.

Ultrasound-promoted intramolecular direct arylation in a capillary flow microreactor

An intramolecular direct arylation of various aryl bromides was performed using ultrasonic irradiation and a continuous flow capillary microreactor. The present procedure provided a higher functional group tolerance, ligand-free, milder reaction conditions and a shorter reaction time for the direct arylation compared with the conventional methods. The ultrasonic irritation not only greatly promoted the conversion and selectivity of the direct arylation, but also solved the clogging problem of the microreactor for solid-forming reaction and made the reaction run smoothly.

Synthesis and anticonvulsant activity of 1-(2-(8-(benzyloxy)quinolin-2-yl)-1-butyrylcyclopropyl)-3-substituted urea derivatives

In the present study on the development of new anticonvulsants, 16 new1-(2-(8-(benzyloxy)quinolin-2-yl)-1-butyrylcyclopropyl)-3-substituted urea derivatives were synthesized and tested for anticonvulsant activity using the maximal electroshock seizure, subcutaneous pentylenetetrazole screens, which are the most widely employed seizure models for early identification of candidate anticonvulsants. Their neurotoxicity was determined by applying the rotorod test. Three compounds 7a, 7e, and 7m showed promising anticonvulsant activities in both models employed for anticonvulsant evaluation. The most active compound 7e showed the maximal electroshock seizure-induced seizures with ED(50) value of 14.3 mg/kg and TD(50) value of 434 mg/kg after intraperitoneal injection to mice, which provided compound 7e with a protective index (TD(50) /ED(50) ) of 30.3 in the maximal electroshock seizure test.

Quinoline-based compounds as modulators of HIV transcription through NF-kappaB and Sp1 inhibition

18 quinoline-based compounds were tested for antiviral properties against human immunodeficiency syndrome (HIV). The compounds tested here contain quinoline or tetrahydroquinoline rings and can be divided into two main groups: group 1 includes 4-(2-oxopyrrolidinyl-1)-1,2,3,4-tetrahydroquinolines with 2-(3-nitrophenyl) substituent (N-series) or 2-(3-aminophenyl) moiety (H-series), and group 2 includes 2-(3-nitrophenyl)- or 2-(3-aminophenyl)-substituted quinolines (S-series). Two different antiviral assays were performed in order to test the anti-HIV activity of compounds: 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and recombinant virus assay (RVA). Results showed that the most active compounds were 2-aryl quinolines, particularly those containing methoxy substituents or no substituents in the quinoline skeleton. HIV transcription inhibition appears to be their target in both resting and phorbol myristate acetate (PMA) activated primary lymphocytes, and nuclear factor-kappaB (NF-kappaB) and specificity protein-1 (SP1) seems to be the most important transcription factors involved in their action.

Synthesis of a novel series of diphenolic chromone derivatives as inhibitors of NO production in LPS-activated RAW264.7 macrophages

A novel series of diphenolic chromone derivatives were synthesized and their inhibitory activity on nitric oxide (NO) production and cytotoxicity were evaluated using LPS-activated murine macrophages RAW264.7 assay and MTT method, respectively. Among these compounds, (5,7-dihydroxy-4-oxo-4H-chromen-3-yl) methyl esters (6b, 6c, 6f, 6g, and 6h) showed quite potent inhibitory activities with IC(50) values of 2.20, 3.48, 0.35, 0.80, and 0.61microM, respectively. The MTT results showed that all of the active compounds exhibited no cytotoxicity at the effective concentrations. The preliminary mechanism of the most potent compounds (6b, 6c, 6f, 6g, and 6h) was further examined based on the RT-PCR results and the compounds 6f, 6g, and 6h inhibited NO production by suppressing the expression of iNOS mRNA in a dose dependent manner. Furthermore, a computational analysis of physicochemical parameters revealed that the most of the compounds possessed drug-like properties.