Targeting kinases with anilinopyrimidines: Discovery of N-phenyl-N'-[4-(pyrimidin-4-ylamino)phenyl]urea derivatives as selective inhibitors of class III receptor tyrosine kinase subfamily

Kinase inhibitors are attractive drugs/drug candidates for the treatment of cancer. The most recent literature has highlighted the importance of multi target kinase inhibitors, although a correct balance between specificity and non-specificity is required. In this view, the discovery of multityrosine kinase inhibitors with subfamily selectivity is a challenging goal. Herein we present the synthesis and the preliminary kinase profiling of a set of novel 4-anilinopyrimidines. Among the synthesized compounds, the N-phenyl-N\u2019-[4-(pyrimidin-4-ylamino)phenyl]urea derivatives selectively targeted some members of class III receptor tyrosine kinase family. Starting from the structure of hit compound 19 we synthesized a further compound with an improved affinity toward the class III receptor tyrosine kinase members and endowed with a promising antitumor activity both in vitro and in vivo in a murine solid tumor model. Molecular modeling simulations were used in order to rationalize the behavior of the title compounds

Difurocoumarins, Psoralen Analogs: Synthesis and DNA Photobinding

A new tetracyclic derivative, difurocoumarin, was synthesized and studied in order to ascertain its possible use as a photochemotherapeutic agent alternative to psoralens. The compound proved able to photobind monofunctionally to DNA on irradiation with UV-A. A photocycloadduct with thymine was isolated and characterized spectroscopically

Corilagin Induces High Levels of Apoptosis in the Temozolomide-Resistant T98G Glioma Cell Line

Glioblastoma multiforme (GBM), a malignant tumor of the central nervous system, has a high mortality rate; no curativetreatment is presently available and the most commonly used chemiotherapeutic drug, the alkylating agent temozolomide (TMZ), is only able to increase life expectancy and is often associated with drugresistance. Therefore, an urgent need does exist for novel drugs aimed at treating gliomas. In the present study we obtained three major results using corliagin: (a) demonstrate that it inhibits the growth of U251 glioma cells through activation of the apoptotic pathway; (b) demonstrate that it is also active on temozolomideresistant T98G glioma cells; (c) demonstrate that when used in combination with temozolomide on T98G glioma cells a higher level of pro-apototic and antiproliferative effects are observed. Our study indicates that corilagin should be investigated in more detail in order to determine if it can be developed as a potential therapeutic agent. In addition, our results suggest that corilagin could be used in combination with low dosages of other standard anticancer chemotherapeutic drugs against gliomas (such as temozolomide) with the aim of obtaining enhanced anticancer effects

Molecular mechanism of action of trimethylangelicin derivatives as CFTR modulators

The psoralen-related compound, 4,6,40-trimethylangelicin (TMA) potentiates the cAMP/PKA-dependent activation of WT-CFTR and rescues F508del-CFTR-dependent chloride secretion in both primary and secondary airway cells homozygous for the F508del mutation. We recently demonstrated that TMA, like lumacaftor (VX-809), stabilizes the first membrane-spanning domain (MSD1) and enhances the interface between NBD1 and ICL4 (MSD2). TMA also demonstrated anti-inflammatory properties, via reduction of IL-8 expression, thus making TMA a promising agent for treatment of cystic fibrosis. Unfortunately, TMA was also found to display potential phototoxicity and mutagenicity, despite the fact that photo-reactivity is absent when the compound is not directly irradiated with UVA light. Due to concerns about these toxic effects, new TMA analogs, characterized by identical or better activity profiles and minimized or reduced side effects, were synthesized by modifying specific structural features on the TMA scaffold, thus generating compounds with no mutagenicity and phototoxicity. Among these compounds, we found TMA analogs which maintained the potentiation activity of CFTR in FRT-YFP-G551D cells. Nanomolar concentrations of these analogs significantly rescued F508del CFTR-dependent chloride efflux in FRT-YFP-F508del, HEK-293 and CF bronchial epithelial cells. We then investigated the ability of TMA analogs to enhance the stable expression of varying CFTR truncation mutants in HEK-293 cells, with the aim of studying the mechanism of their corrector activity. Not surprisingly, MSD1 was the smallest domain stabilized by TMA analogs, as previously observed for TMA. Moreover, we found that TMA analogs were not effective on F508del-CFTR protein which was already stabilized by a second-site mutation at the NBD1-ICL4 interface. Altogether, our findings demonstrate that these TMA analogs mediate correction by modifying MSD1 and indirectly stabilizing the interface between NBD1 and CL4

Emergent treatments for β-thalassemia and orphan drug legislations

In many countries, β-thalassemia (β-THAL) is not uncommon; however, it qualifies as a rare disease in the US and in European Union (EU), where thalassemia drugs are eligible for Orphan Drug Designation (ODD). In this paper, we evaluate all 28 ODDs for β-THAL granted since 2001 in the US and the EU: of these, ten have since been discontinued, twelve are pending, and six have become licensed drugs available for clinical use. The prime mover for these advances has been the increasing depth of understanding of the pathophysiology of β-THAL; at the same time, and even though only one-fifth of β-THAL ODDs have become licensed drugs, the ODD legislation has clearly contributed substantially to the development of improved treatments for β-THAL

QSAR and 3D-QSAR Models in the Field of Tubulin Inhibitors as Anticancer Agents

Microtubules are high dynamic protein filaments fundamental for cells growth and proliferation. Hence, tubulin inhibitors are useful anticancer compounds. Three major binding site have been identified in tubulin, on the basis of known ligands: the vinca domain, the colchicine domain and the taxane domain. Several compounds able to bind the colchicine and the taxane domains have been to date synthesized and evaluated. In this review we give a description of the developed QSAR and 3D-QSAR models, giving particular attention to those studies that give structural insight in the binding modes of compounds with the target

Autogrid-based clusterization of kinases: selection of representative conformations for docking purposes

The selection of the most appropriate protein conformation is a crucial aspect in molecular docking experiments. In order to reduce the errors arising from the use of a single protein conformation, several authors suggest the use of several tridimensional structures for the target. However, the selection of the most appropriate protein conformations still remains a challenging goal. The protein 3D-structures selection is mainly performed based on pairwise root-meansquare-deviation (RMSD) values computation, followed by hierarchical clustering. Herein we report an alternative strategy, based on the computation of only two atom affinity map for each protein conformation, followed by multivariate analysis and hierarchical clustering. This methodology was applied on seven different kinases of pharmaceutical interest. The comparison with the classical RMSD-based strategywas based on cross-docking of co-crystallized ligands. In the case of epidermal growth factor receptor kinase, also the docking performance on 220 known ligands were evaluated, followed by 3D-QSAR studies. In all the cases, the herein proposed methodology outperformed the RMSD-based one

Quinazoline derivatives as potential anticancer agents: a patent review (2007 \u2013 2010)

Introduction : Due to the increase in knowledge about cancer pathways, there is a growing interest in finding novel potential drugs. Quinazoline is one of the most widespread scaffolds amongst bioactive compounds. A number of patents and papers appear in the literature regarding the discovery and development of novel promising quinazoline compounds for cancer chemotherapy. Although there is a progressive decrease in the number of patents filed, there is an increasing number of biochemical targets for quinazoline compounds. Areas covered : This paper provides a comprehensive review of the quinazolines patented in 2007 - 2010 as potential anticancer agents. Information from articles published in international peer-reviewed journals was also included, to give a more exhaustive overview. Expert opinion : From about 1995 to 2006, the anticancer quinazolines panorama has been dominated by the 4-anilinoquinazolines as tyrosine kinase inhibitors. The extensive researches conducted in this period could have caused the progressive reduction in the ability to file novel patents as shown in the 2007 - 2010 period. However, the growing knowledge of cancer-related pathways has recently highlighted some novel potential targets for therapy, with quinazolines receiving increasing attention. This is well demonstrated by the number of different targets of the patents considered in this review. The structural heterogeneity in the patented compounds makes it difficult to derive general pharmacophores and make comparisons among claimed compounds. On the other hand, the identification of multi-target compounds seems a reliable goal. Thus, it is reasonable that quinazoline compounds will be studied and developed for multi-target therapies

Isomerization of 4-Aminobenzofurans to 4-Hydroxyindoles.

4-Amino-2-methylbenzofurans are quantitatively converted to 4-hydroxy-2-methylindoles in acidic medium. The rearrangement mechanism involves the ring opening of the furan ring to produce an intermediate carbocation, which undergoes ring closure to the indole system. Isomerization takes place only in the presence of a methyl substituent in 2 position

Microwave-promoted mono-N-alkylation of aromatic amines in water: a new efficient and green method for an old and problematic reaction

A greener improvement to direct mono-N-alkylation of aromatic amines by alkyl halides was achieved using microwave irradiation in water without any catalyst. The reaction was carried out in water at 150 \ub0C with twice the amount of the appropriate alkyl halide and without any catalyst. This synthetic procedure works very well with a variety of arylamines and in a satisfactory way also with deactivated amines; it allows only mono-N-alkylated products to be obtained and it is chemoselective in the presence of more than one functional group. The reaction is efficient, rapid and clean. The described method could be a useful synthetic way to achieve alkylarylamines avoiding the use of organic solvents and catalysts or additives