Antitumor 2,3-dihydro-2-(aryl)-4(1H)-quinazolinone derivatives. Interactions with tubulin

2,3-Dihydroquinazolin-4(1H)-ones and quinazolin-4(3H)-ones as broad-spectrum cytotoxic agents and their impact on tubulin polymerisation

Tubulin plays a central role in mitosis and has been the target of multiple anticancer drugs, including paclitaxel. Herein two separate families of 2,3-dihydroquinazoline-4(1H)-ones and quinazoline-4(3H) ones, comprising 57 compounds in total, were synthesised. Screening against a broad panel of human cancer cell lines (HT29 colon, U87 and SJ-G2 glioblastoma, MCF-7 breast, A2780 ovarian, H460 lung, A431 skin, Du145 prostate, BE2-C neuroblastoma, and MIA pancreas) reveals these analogues to be broad spectrum cytotoxic compounds. Of particular note, 2-styrylquinazolin-4(3H)-one 51, 2-(4-hydroxystyryl)quinazolin-4(3H)-one 63, 2-(2-methoxystyryl)quinazolin-4(3H)-one 64 and 2-(3-methoxystyryl)quinazolin-4(3H)-one 65 and 2-(naphthalen-1-yl)-2,3-dihydroquinazolin-4(1H)-one 39 exhibited sub-μM potency growth inhibition values. Of these 1-naphthyl 39 has activity <50 nM against the HT29, U87, A2780, H460 and BE2-C cell lines. Molecular modelling of these compounds, e.g. 2-(naphthalen-1-yl)-2,3-dihydroquinazolin-4(1H)-one 39, 2-(2-methoxystyryl)quinazolin-4(3H)-one 64, 2-(3-methoxystyryl)quinazolin-4(3H)-one 65, and 2-(4-methoxystyryl)quinazolin-4(3H)-one 50 docked to the known tubulin polymerisation inhibitor sites highlighted well conserved interactions within the colchicine binding pocket. These compounds were examined in a tubulin polymerisation assay alongside the known tubulin polymerisation promotor, paclitaxel (69), and tubulin inhibitor, nocodazole (68). Of the analogues examined, indoles 43 and 47 were modest promotors of tubulin polymerisation, but less effective than paclitaxel. Analogues 39, 64, and 65 showed reduced microtubule formation consistent with tubulin inhibition. The variation in ring methoxy substituent with 50, 64 and 65, from o- to m- to p-, results in a concomitant reduction in cytotoxicity and a reduction in tubulin polymerisation, with p-OCH350 being the least active in this series of analogues. This presents 64 as a tubulin polymerisation inhibitor possessing novel chemotype and sub micromolar cytotoxicity. Naphthyl 39, with complete inhibition of tubulin polymerisation, gave rise to a sub 0.2 μM cell line cytotoxicity. Compounds 39 and 64 induced G2 + M cell cycle arrest indicative of inhibition of tubulin polymerisation, with 39 inducing an equivalent effect on cell cycle arrest as nocodazole (68).

Design, synthesis, molecular docking, and molecular dynamic studies of novel quinazoline derivatives as phosphodiesterase 7 inhibitors

Introduction: Phosphodiesterase 7 (PDE7) is a high-affinity cyclic AMP (cAMP)-specific PDE that is expressed in immune and proinflammatory cells. In this work, we explore the possibility that selective small molecule inhibitors of this enzyme family could provide a novel approach to alleviate the inflammation that is associated with many inflammatory diseases. Methods: A series of novel substituted 4-hydrazinoquinazoline derivatives and fused triazoloquinazolines were designed, synthesized, and evaluated in vitro for their PDE7A inhibition activities, in comparison with Theophylline, a non-selective PDE inhibitor, and BRL50481, a selective PDE7A inhibitor. This series of novel quinazoline derivatives were synthesized via multi-step reactions. The reaction sequence began with selective monohydrazinolysis of compounds 2a,b to give 3a,b. Schiff bases 4a-h were synthesized by the reaction of the quinazolylhydrazines 3a,b with various substituted aromatic aldehydes. The reaction of 4a-h with bromine in acetic acid, in turn, gave fused triazoloquinazolines 5a-h. These compounds were characterized by satisfied spectrum analyses mainly including 1HNMR, 13CNMR, and MS together with elemental analyses. Results and discussion: The results of in vitro PDE7A inhibition activity clearly indicated that compounds 4b, 4g, 5c, and 5f exhibited good potency. Molecular docking and molecular dynamic simulation studies further supported our findings and provided the basis of interaction in terms of conventional hydrogen bonds and π-π stacking patterns. The present results lay the groundwork for developing lead compounds with improved phosphodiesterase seven inhibitory activities.

Room temperature ligand-free Cu2O-H2O2 catalyzed tandem oxidative synthesis of quinazoline-4(3H)-one and quinazoline derivatives

An efficient and simple copper catalytic system has been developed for the synthesis of medicinally important 2-substituted quinazoline-4(3H)-ones from 2-aminobenzonitrile and benzyl alcohol derivatives and additionally 2-substituted quinazolines from 2-aminobenzylamine and benzaldehyde derivatives. Mild oxidant H₂O₂ was utilized, providing excellent product yields. The molecular structure of one of the compounds was substantiated through SC-XRD. The versatility of the protocol was demonstrated through gram-scale syntheses.

A Review of the Recent Developments of Molecular Hybrids Targeting Tubulin Polymerization

Microtubules are cylindrical protein polymers formed from αβ-tubulin heterodimers in the cytoplasm of eukaryotic cells. Microtubule disturbance may cause cell cycle arrest in the G2/M phase, and anomalous mitotic spindles will form. Microtubules are an important target for cancer drug action because of their critical role in mitosis. Several microtubule-targeting agents with vast therapeutic advantages have been developed, but they often lead to multidrug resistance and adverse side effects. Thus, single-target therapy has drawbacks in the effective control of tubulin polymerization. Molecular hybridization, based on the amalgamation of two or more pharmacophores of bioactive conjugates to engender a single molecular structure with enhanced pharmacokinetics and biological activity, compared to their parent molecules, has recently become a promising approach in drug development. The practical application of combined active scaffolds targeting tubulin polymerization inhibitors has been corroborated in the past few years. Meanwhile, different designs and syntheses of novel anti-tubulin hybrids have been broadly studied, illustrated, and detailed in the literature. This review describes various molecular hybrids with their reported structural-activity relationships (SARs) where it is possible in an effort to generate efficacious tubulin polymerization inhibitors. The aim is to create a platform on which new active scaffolds can be modeled for improved tubulin polymerization inhibitory potency and hence, the development of new therapeutic agents against cancer.

Sulfonated β-cyclodextrins: efficient supramolecular organocatalysts for diverse organic transformations

The present review summarizes various organic transformations carried out by using sulfonated β-cyclodextrins such as β-cyclodextrin sulfonic acid, β-cyclodextrin propyl sulfonic acid, and β-cyclodextrin butyl sulfonic acid as an efficient, supramolecular reusable catalyst under diverse reaction conditions.

Identification of novel microtubule inhibitors effective in fission yeast and human cells and their effects on breast cancer cell lines

Microtubules are critical for a variety of cellular processes such as chromosome segregation, intracellular transport and cell shape. Drugs against microtubules have been widely used in cancer chemotherapies, though the acquisition of drug resistance has been a significant issue for their use. To identify novel small molecules that inhibit microtubule organization, we conducted sequential phenotypic screening of fission yeast and human cells. From a library of diverse 10 371 chemicals, we identified 11 compounds that inhibit proper mitotic progression both in fission yeast and in HeLa cells. An in vitro assay revealed that five of these compounds are strong inhibitors of tubulin polymerization. These compounds directly bind tubulin and destabilize the structures of tubulin dimers. We showed that one of the compounds, L1, binds to the colchicine-binding site of microtubules and exhibits a preferential potency against a panel of human breast cancer cell lines compared with a control non-cancer cell line. In addition, L1 overcomes cellular drug resistance mediated by βIII tubulin overexpression and has a strong synergistic effect when combined with the Plk1 inhibitor BI2536. Thus, we have established an economically effective drug screening strategy to target mitosis and microtubules, and have identified a candidate compound for cancer chemotherapy.

β-Cyclodextrin: a supramolecular catalyst for metal-free approach towards the synthesis of 2-amino-4,6-diphenylnicotinonitriles and 2,3-dihydroquinazolin-4(1H)-one

β-Cyclodextrin, a green and widespread supramolecular catalyst, has been explored as a highly proficient promoter for the metal-free one-pot multi-component synthesis of a vast range of highly functionalized bioactive heterocyclic moiety, 2-amino-4,6-diphenylnicotinonitriles and 2,3-dihydroquinazolin-4(1H)-one, from easily available precursor aldehydes. The main endeavor of these protocols is to explore this organic supramolecule in one-pot multi-component synthesis. Absence of metal catalyst or toxic acid and harsh reaction conditions, excellent functional group tolerance, inexpensive, greener and environmentally safe protocol are the key advantages of this work.

Recent advances in the pharmacological diversification of quinazoline/quinazolinone hybrids

Due to the pharmacological activities of quinazoline and quinazolinone scaffolds, it has aroused great interest in medicinal chemists for the development of new drugs or drug candidates. The pharmacological activities of quinazoline and its related scaffolds include anti-cancer, anti-microbial, anti-convulsant, and antihyperlipidaemia. Recently, molecular hybridization technology is used for the development of hybrid analogues with improved potency by combining two or more pharmacophores of bioactive scaffolds. The molecular hybridization of various biologically active pharmacophores with quinazoline derivatives resulted in lead compounds with multi-faceted biological activity wherein specific as well as multiple targets were involved. The present review summarizes the advances in lead compounds of quinazoline hybrids and their related heterocycles in medicinal chemistry. Moreover, the review also helps to intensify the drug development process by providing an understanding of the potential role of these hybridized pharmacophoric features in exhibiting various pharmacological activities.

Recent advances in quinazoline/quinazolinone hybrid heterocycles in medicinal chemistry and their pharmacological diversification.

Facile Synthesis of 2,3-Dihydro-2-Aryl-4(1H)-Quinazolinones Promoted by SmI2

2,3-Dihydro-2-aryl-4(1H)-quinazolinones were prepared in good yields via reductive cyclisation of o-azidobeneamides with aldehydes and ketones promoted by SmI2 under mild and neutral conditions.

A Novel Microtubule Inhibitor Overcomes Multidrug Resistance in Tumors

Microtubule inhibitors as chemotherapeutic drugs are widely used for cancer treatment. However, the development of multidrug resistance (MDR) in cancer is a major challenge for microtubule inhibitors in their clinical implementation. From a high-throughput drug screen using cells transformed by oncogenic RAS, we identify a lead heteroaryl amide compound that blocks cell proliferation. Analysis of the structure-activity relationship indicated that this series of scaffolds (exemplified by MP-HJ-1b) represents a potent inhibitor of tumor cell growth. MP-HJ-1b showed activities against a panel of more than 1,000 human cancer cell lines with a wide variety of tissue origins. This compound depolymerized microtubules and affected spindle formation. It also induced the spike-like conformation of microtubules in vitro and in vivo, which is different from typical microtubule modulators. Structural analysis revealed that this series of compounds bound the colchicine pocket at the intra-dimer interface, although mostly not overlapping with colchicine binding. MP-HJ-1b displayed favorable pharmacological properties for overcoming tumor MDR, both in vitro and in vivo Taken together, our data reveal a novel scaffold represented by MP-HJ-1b that can be developed as a cancer therapeutic against tumors with MDR.Significance: Paclitaxel is a widely used chemotherapeutic drug in patients with multiple types of cancer. However, resistance to paclitaxel is a challenge. This study describes a novel class of microtubule inhibitors with the ability to circumvent multidrug resistance across multiple tumor cell lines. Cancer Res; 78(20); 5949-57. ©2018 AACR.

2,3-Dihydroquinazolin-4(1H)-one as a privileged scaffold in drug design

2,3-Dihydroquinazolin-4-one (DHQ) belongs to the class of nitrogen-containing heterocyclic compounds representing a core structural component in various biologically active compounds. In the past decades, several methodologies have been developed for the synthesis of the DHQ framework, especially the 2-substituted derivatives. Unfortunately, multistep syntheses, harsh reaction conditions, and the use of toxic reagents and solvents have limited their full potential as a versatile fragment. Recently, use of green chemistry and alternative strategies are being explored to prepare diverse DHQ derivatives. This fragment is used as a synthon for the preparation of biologically active quinazolinones and as a functional substrate for the synthesis of modified DHQ derivatives exhibiting different biological properties. In this review, we provide a comprehensive assessment of the synthesis and biological evaluations of DHQ derivatives.

Design, synthesis and biological evaluation of some novel quinazolinone derivatives as potent apoptotic inducers

Aim: Novel quinazolinone and triazinoquinazolinone derivatives were designed and synthesized as apoptotic inducers. Methodology/results: Most of the synthesized compounds showed excellent antiproliferative activity against MCF-7 and HCT-116 cell lines, respectively. Compounds 7a, 8a, 8d, 14a and 14d were superior to doxorubicin as activators of caspases 3, 8 and 9 in HCT-116 cell line. The most potent caspase inducers, 8d and 14a showed cell cycle arrest mainly in G1 and S phase, respectively and increased the levels of p53, Bax and the Bax/Bcl-2 ratio compared with doxorubicin in HCT-116 cells with excellent selectivity against CCD-18Co human colon normal cell line. Conclusion: The synthesized compounds can be considered as potent apoptotic inducers interfering with extrinsic and intrinsic apoptotic pathways.

Oxone-mediated annulation of 2-aminobenzamides and 1,2-diaminobenzenes withsec-aminesviaimine-N-oxides: new syntheses of 2,3-dihydroquinazolin-4(1H)-ones and 1H-benzimidazoles

Synthesis of 2,3-dihydroquinazolin-4(1H)-ones and 1H-benzimidazoles by reaction of imine-N-oxides with 2-aminobenzamides and 1,2-diaminobenzenes is described.

Synthesis and Biological Evaluation of N-[2-(4-Hydroxyphenylamino)-pyridin-3-yl]-4-methoxy-benzenesulfonamide (ABT-751) Tricyclic Analogues as Antimitotic and Antivascular Agents with Potent in Vivo Antitumor Activity

Benzopyridothiadiazepine (2a) and benzopyridooxathiazepine (2b) were modified to produce tricyclic quinazolinone 15-18 or benzothiadiazine 26-27 derivatives. These compounds were evaluated in cytotoxicity and tubulin inhibition assays and led to potent inhibitors of tubulin polymerization. N-[2(4-Methoxyphenyl)ethyl]-1,2-dihydro-pyrimidino[2,1-b]quinazolin-6-one (16a) exhibited the best in vitro cytotoxic activity (GI50 10-66.9 nM) against the NCI 60 human tumor cell line and significant potency against tubulin assembly (IC50 0.812 μM). In mechanism studies, 16a was shown to block cell cycle in G2/M phase and to disrupt microtubule formation and displayed good antivascular properties as inhibition of cell migration, invasion, and endothelial tube formation. Compound 16a was evaluated in C57BL/6 mouse melanoma B16F10 xenograft model to validate its antitumor activity, in comparison with reference ABT-751 (1). Compound 16a displayed strong in vivo antitumor and antivascular activities at a dose of 5 mg/kg without obvious toxicity, whereas 1 needed a 10-fold higher concentration to reach similar effects.

A choline hydroxide catalyzed synthesis of 2,3-dihydroquinazolin-4(1H)-ones in an aqueous medium

A simple, metal and ligand-free protocol for the synthesis of 2,3-dihydroquinazolin-4(1H)-one derivatives using choline hydroxide (ChOH) as an effective catalyst in an aqueous medium has been developed.

Hydroxyapatite nanoparticles (HAP NPs): a green and efficient heterogeneous catalyst for three-component one-pot synthesis of 2,3-dihydroquinazolin-4(1H)-one derivatives in aqueous media

HAP NPs were applied as a green heterogeneous catalyst for synthesis of 2,3-dihydroquinazolin-4(1H)-one derivatives. The nanocatalyst was prepared and characterized.

Synthesis of 2,3-dihydroquinazolinones and quinazolin-4(3H)-ones catalyzed by graphene oxide nanosheets in an aqueous medium: “on-water” synthesis accompanied by carbocatalysis and selective C–C bond cleavage

Graphene oxide nanosheet catalyzed strategies for construction of 2,3-dihydroquinazolinones and quinazolin-4(3H)-ones starting from anthranilamide and an aldehyde/ketone in aqueous medium at room temperature have been realized.

Schiff's bases of quinazolinone derivatives: Synthesis and SAR studies of a novel series of potential anti-inflammatory and antioxidants

A series of quinazolinone derived Schiff base derivatives 7-28 were synthesized and characterized as novel antioxidants and anti-inflammatory agents. The in vitro antioxidant activities of these compounds were evaluated and compared with commercial antioxidants ascorbic acid (AA), gallic acid (GA), butylatedhydroxytoluene (BHT), butylatedhydroxyanisole (BHA) employing 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay, 2,2-azinobis-(3-ethylbenzothiazoline-6-sufonic acid) (ABTS) assay and N,N-dimethyl-p-phenylenediamine dihydrochloride (DMPD) assay. The results revealed that IC50 of 17, 18, 23, 24, 25, 27 and 28 were lower than the IC50 of standards in all the three performed antioxidant assays indicating good activities of these compounds. In addition, in vitro anti-inflammatory activity of the synthesized compounds were evaluated and the results demonstrate that the compounds 9-12 exhibited excellent anti-inflammatory activity. Preliminary structure-activity relationship revealed that the compounds 17, 18, 23, 24, 25, 27 and 28 with electron donating moiety (OH, OCH3) were found to be excellent antioxidants and compounds 9, 10, 11 and 12 with electron withdrawing moiety (Cl, NO2) were found to be excellent anti-inflammatory agents.

Identification of diaryl 5-amino-1,2,4-oxadiazoles as tubulin inhibitors: the special case of 3-(2-fluorophenyl)-5-(4-methoxyphenyl)amino-1,2,4-oxadiazole

The combination of experimental (inhibition of colchicine binding) and computational (COMPARE, docking studies) data unequivocally identified diaryl 5-amino-1,2,4-oxadiazoles as potent tubulin inhibitors. Good correlation was observed between tubulin binding and cytostatic properties for all tested compounds with the notable exception of the lead candidate, 3-(3-methoxyphenyl)-5-(4-methoxyphenyl)amino-1,2,4-oxadiazole (DCP 10500078). This compound was found to be substantially more active in our in vitro experiments than the monofluorinated title compound, 3-(2-fluorophenyl)-5-(4-methoxyphenyl)amino-1,2,4-oxadiazole (DCP 10500067/NSC 757486), which in turn demonstrated slightly better tubulin binding activity. Comparative SAR analysis of 25 diaryl 5-amino-1,2,4-oxadiazoles with other known tubulin inhibitors, such as combretastatin A-4 (CA-4) and colchicine, provides further insight into the specifics of their binding as well as a plausible mechanism of action.

Synthesis, tautomeric structure and antimicrobial activity of 3-arylhydrazono-4-phenyl-[1,2,4]-triazepino[2,3-a]quinazoline-2,7(1H)-diones

A simple strategy for the synthesis of the hitherto unreported 3-arylazo-4-phenyl-[1,2,4]triazepino[2,3-H]quinazoline-2,7(1H)-diones is described. Spectral data indicated that the studied compounds exist predominantly in the hydrazone tautomeric form. The antimicrobial activity of the newly synthesized compounds was also evaluated. The results indicated that some of these compounds have moderate activity towards bacteria.