Caffeine–hydrazones as anticancer agents with pronounced selectivity toward T-lymphoblastic leukaemia cells

Caffeine and Purine Derivatives: A Comprehensive Review on the Chemistry, Biosynthetic Pathways, Synthesis-Related Reactions, Biomedical Prospectives and Clinical Applications

Caffeine and purine derivatives represent interesting chemical moieties, which show various biological activities. Caffeine is an alkaloid that belongs to the family of methylxanthine alkaloids and it is present in food, beverages, and drugs. Coffee, tea, and some other beverages are a major source of caffeine in the human diet. Caffeine can be extracted from tea or coffee using hot water with dichloromethane or chloroform and the leftover is known as decaffeinated coffee or tea. Caffeine and its derivatives were synthesized via different procedures on small and large scales. It competitively antagonizes the adenosine receptors (ARs), which are G protein-coupled receptors largely distributed in the human body, including the heart, vessels, brain, and kidneys. Recently, many reports showed the effect of caffeine derivatives in the treatment of many diseases such as Alzheimer's, asthma, parkinsonism, and cancer. Also, it is used as an antioxidant, anti-inflammatory, analgesic, and hypocholesterolemic agent. The present review article discusses the synthesis, reactivity, and biological and pharmacological properties of caffeine and its derivatives. The biosynthesis and biotransformation of caffeine in coffee and tea leaves and the human body were summarized in the review.

TET protein inhibitors: Potential and limitations

TET proteins (methylcytosine dioxygenases) play an important role in the regulation of gene expression. Dysregulation of their activity is associated with many serious pathogenic states such as oncological diseases. Regulation of their activity by specific inhibitors could represent a promising therapeutic strategy. Therefore, this review describes various types of TET protein inhibitors in terms of their inhibitory mechanism and possible applicability. The potential and possible limitations of this approach are thoroughly discussed in the context of TET protein functionality in living systems. Furthermore, possible therapeutic strategies based on the inhibition of TET proteins are presented and evaluated, especially in the field of oncological diseases.

Design, synthesis, anticancer and in silico assessment of 8-piperazinyl caffeinyl-triazolylmethyl hybrid conjugates

In this paper, we have assessed the design, synthesis, characterization, anticancer properties, toxicity, and in silico study of 8-piperazinyl caffeinyl-triazolylmethyl derivatives as new caffeine hybrid conjugates. These compounds consist of four moieties comprising 8-caffeinyl, piperazinyl, 1,2,3-triazolyl, and alkyl substituents. The synthesis of these compounds was started by bromination of caffeine to attain 8-BC, SNAr reaction with piperazine to acquire 8-PC, N-propargylation of 8-PC and finally click Huisgen cycloaddition with diverse alkyl azides. These compounds were in vitro tested against two significant cancer cell lines comprising breast cancer MCF-7 (ATCC HTB-22) and melanoma cancer A-375 (ATCC CRL-1619) cell lines and activities compared with methotrexate (MTX) as a reference drug. Anticancer assessments indicated 12j (IC50 = 323 ± 2.6) and 12k (IC50 = 175 ± 3.2) were the most potent compounds against A-375 and MCF-7 cell growth, respectively and their activities were even stronger than MTX (IC50 = 418 ± 2 for A375 and IC50 = 343 ± 3.6 for MCF-7). Toxicities were determined by screening compounds against normal cell line HEK-293 (ATCC CRL-11268) and indicated that except 12i (IC50 = 371 ± 2.3), 12j (IC50 = 418 ± 2.4), and MTX (IC50 = 199 ± 2.4), all compounds are non-toxic. Docking was conducted for 12j and 12k and determined the strong binding affinities to B-RAF kinase and hDHFR enzymes, respectively. In silico pharmacokinetic and physiochemical profiles of tested compounds were investigated which indicated that most compounds obeyed Lipinski's rule of five (RO5). The DFT study on M06-2X/6-311G (d,p) was used to indicate HOMO, LUMO, MEP, and other parameters for a better understanding of 12j and 12k reactivity. Owing to anticancer properties, toxicity, and in silico data, 12j and 12k can be proposed for further research in the future.

Chromone Containing Hybrid Analogs: Synthesis and Applications in Medicinal Chemistry

The use of privileged scaffolds has proven beneficial for generating novel bioactive scaffolds in drug discovery program. Chromone is one such privileged scaffold that has been exploited for designing pharmacologically active analogs. The molecular hybridization technique combines the pharmacophoric features of two or more bioactive compounds to avail a better pharmacological activity in the resultant hybrid analogs. The current review summarizes the rationale and techniques involved in developing hybrid analogs of chromone, which show potential in fields of obesity, diabetes, cancer, Alzheimer's disease and microbial infections. Here the molecular hybrids of chromone with various pharmacologically active analogs or fragments (donepezil, tacrine, pyrimidines, azoles, furanchalcones, hydrazones, quinolines, etc.) are discussed with their structure-activity relationship against above-mentioned diseases. Detailed methodologies for the synthesis of corresponding hybrid analogs have also been described, with suitable synthetic schemes. The current review will shed light on various strategies utilized for the design of hybrid analogs in the field of drug discovery. The importance of hybrid analogs in various disease conditions is also illustrated.

Design, Synthesis and Cytotoxic Activity of Novel Salicylaldehyde Hydrazones against Leukemia and Breast Cancer

Despite the significant advancements in complex anticancer therapy, the search for new and more efficient specific anticancer agents remains a top priority in the field of drug discovery and development. Here, based on the structure-activity relationships (SARs) of eleven salicylaldehyde hydrazones with anticancer activities, we designed three novel derivatives. The compounds were tested in silico for drug-likeness, synthesized, and evaluated in vitro for anticancer activity and selectivity on four leukemic cell lines (HL-60, KE-37, K-562, and BV-173), one osteosarcomic cell line (SaOS-2), two breast adenocarcinomic cell lines (MCF-7 and MDA-MB-231), and one healthy cell line (HEK-293). The designed compounds were found to have appropriate drug likeness and showed anticancer activities in all cell lines tested; particularly, two of them exhibited remarkable anticancer activity in nanomolar concentrations on the leukemic cell lines HL-60 and K-562 and the breast cancer MCF-7 cells and extraordinary selectivity for the same cancer lines ranging between 164- and 1254-fold. The study also examined the effects of different substituents on the hydrazone scaffold and found that the 4-methoxy salicylic moiety, phenyl, and pyridinyl rings are the most appropriate for anticancer activity and selectivity of this chemical class.

Design, synthesis, anticancer and in silico assessment of 8-caffeinyl-triazolylmethoxy hybrid conjugates

In this research the synthesis, characterization, anticancer and the cytotoxicity assessments of novel 8-caffeinyl-triazolylmethoxy hybrid conjugates have been described. These compounds are the first caffeine-1,2,3-triazolyl hybrid molecules that structurally are composed of three compartments comprising caffeinyl, 1,2,3-triazolyl and N-alkyl/aryl residues. The in vitro evaluations of synthesized compounds on cancer cell lines, including two breast cancer cell lines MDA-MB-468 (ATCC HTB-22), MCF-7 (ATCC HTB-22), melanoma cell line A-375 (ATCC CRL-1619) and normal cell line HEK-293 (ATCC CRL-11268) have determined that 22c (IC₅₀ < 12.5 μM) demonstrated potent activity against A375 and its toxicity is even stronger than methotrexate (MTX) as a standard drug. Additionally, 22c involves more selectivity than MTX regarding its non-toxicity for the HEK-293 cell line. Among the tested compounds against two breast cancer cell lines, 22f (IC₅₀ = 136 ± 0.2 and 126 ± 0.6 μM for MCF-7 and MDA-MB-468, respectively) and 22i (IC₅₀ = 165 ± 1.8 and 175 ± 1.4 μM for MCF-7 and MDA-MB-468, respectively) were the most potent compounds but their activities were less than MTX, moreover 22f showed more selectivity regarding its lower toxicity against HEK-293. Overall, 22f displayed general toxicity and selectivity on all tested cancer cell lines. The in silico physicochemical properties, pharmacokinetic profile, and drug likeness predictions were also carried out for all the studied compounds. Most new compounds exhibited zero violation of Lipinski's rule (RO5). A molecular docking study was also conducted to predict the binding mode and the interaction of 22c as the most active anti-melanoma entry with B-RAF V600E kinase enzyme. The docking results determined that 22c exhibited a strong binding affinity to the active site of the enzyme. These findings demonstrated 22c and 22f as potential future anticancer drug candidates.

New Affordable Methods for Large-Scale Isolation of Major Olive Secoiridoids and Systematic Comparative Study of Their Antiproliferative/Cytotoxic Effect on Multiple Cancer Cell Lines of Different Cancer Origins

Olive oil phenols (OOPs) are associated with the prevention of many human cancers. Some of these have been shown to inhibit cell proliferation and induce apoptosis. However, no systematic comparative study exists for all the investigated compounds under the same conditions, due to difficulties in their isolation or synthesis. Herein are presented innovative methods for large-scale selective extraction of six major secoiridoids from olive oil or leaves enabling their detailed investigation. The cytotoxic/antiproliferative bioactivity of these six compounds was evaluated on sixteen human cancer cell lines originating from eight different tissues. Cell viability with half-maximal effective concentrations (EC50) was evaluated after 72 h treatments. Antiproliferative and pro-apoptotic effects were also assessed for the most bioactive compounds (EC50 ≤ 50 μM). Oleocanthal (1) showed the strongest antiproliferative/cytotoxic activity in most cancer cell lines (EC50: 9−20 μM). The relative effectiveness of the six OOPs was: oleocanthal (1) > oleuropein aglycone (3a,b) > ligstroside aglycone (4a,b) > oleacein (2) > oleomissional (6a,b,c) > oleocanthalic acid (7). This is the first detailed study comparing the bioactivity of six OOPs in such a wide array of cancer cell lines, providing a reference for their relative antiproliferative/cytotoxic effect in the investigated cancers.

Azulene hydrazide-hydrazones for selective targeting of pancreatic cancer cells

Dysregulation of iron homeostasis is one of the important processes in the development of many oncological diseases, such as pancreatic cancer. Targeting it with specific agents, such as an iron chelator, are promising therapeutic methods. In this study, we tested the cytotoxicity of novel azulene hydrazide-hydrazone-based chelators against pancreatic cancer cell lines (MIA PaCa-2, PANC-1, AsPC-1). All prepared chelators (compounds 4-6) showed strong cytotoxicity against pancreatic cancer cell lines and high selectivity for cancer cell lines compared to the healthy line. Their cytotoxicity is lower than thiosemicarbazone-based chelators Dp44mT and DpC, but significantly higher than hydroxamic acid-based chelator DFO. The chelator tested showed mitochondrial and lysosomal co-localization and its mechanism of action was based on the induction of hypoxia-inducible factor-1-alpha (HIF-1α), N-myc downstream-regulated gene-1 (NDRG1) and transferrin receptor 1 (TfR1). This strongly implies that the cytotoxic effect of tested chelators could be associated with mitophagy induction. Lipinski's rule of five analyses was performed to determine whether the prepared compounds had properties ensuring their bioavailability. In addition, the drug-likeness and drug-score were calculated and discussed.

Targeting of the Mitochondrial TET1 Protein by Pyrrolo[3,2-b]pyrrole Chelators

Targeting of epigenetic mechanisms, such as the hydroxymethylation of DNA, has been intensively studied, with respect to the treatment of many serious pathologies, including oncological disorders. Recent studies demonstrated that promising therapeutic strategies could potentially be based on the inhibition of the TET1 protein (ten-eleven translocation methylcytosine dioxygenase 1) by specific iron chelators. Therefore, in the present work, we prepared a series of pyrrolopyrrole derivatives with hydrazide (1) or hydrazone (2–6) iron-binding groups. As a result, we determined that the basic pyrrolo[3,2-b]pyrrole derivative 1 was a strong inhibitor of the TET1 protein (IC₅₀ = 1.33 μM), supported by microscale thermophoresis and molecular docking. Pyrrolo[3,2-b]pyrroles 2–6, bearing substituted 2-hydroxybenzylidene moieties, displayed no significant inhibitory activity. In addition, in vitro studies demonstrated that derivative 1 exhibits potent anticancer activity and an exclusive mitochondrial localization, confirmed by Pearson’s correlation coefficient of 0.92.

Assessment of caffeine neurotoxicity using novel biomarkers of neural function in SH-SY5Y cells - Is there a need for environmental concern?

Worldwide usage of caffeine results in its constant release into the aquatic environment and growing concerns related to associated risks. We assessed (neuro)toxicity of environmentally relevant concentrations of caffeine, using novel biomarkers of neural function in SH-SY5Y cells and markers of general toxicity also in HepG2 cells. The RQ-PCR analyses showed that caffeine disturbs the expression of genes encoding several key elements of neurotransmitter pathways, with the most prominent responses observed for serotonin receptor 3A, dopamine receptor D2, monoamine oxidase B and GABA-transaminase. Expression of genes encoding synaptotagmin 10 involved in exocytosis of neurotransmitters and ATPase Na⁺/K⁺ transporting subunit alpha 3 was also disturbed. Caffeine stimulated the activity of monoamine oxidase, while cytotoxicity and effects on mitochondrial membrane potential were not observed. Our study points out the new possible molecular targets of caffeine and suggests that the raising concerns related to its growing environmental presence are justified.

Synthesis and characterization of alkaloid derived hydrazones and their metal (II) complexes

Alkaloids have been known overtime to have medicinal uses. Exploring alkaloid derived hydrazones and their complexes as potential therapeutic agents with a view to improving the medicinal uses of alkaloids are imperative. 1,8-dichloroacridone hydrazone hydrochloride, 1-chloro pilocarpine nitrate-3-chlorophenyl hydrazone and 1-phenethyl-4-piperidone formyl hydrazone ligands were synthesized via Wolff–Kishner condensation reaction. Five metal (II) complexes of cobalt, nickel and manganese were prepared by stirring the ligands with the respective metal salts. The ligands and complexes were characterized using elemental analyses, molar conductivity, FTIR, 1H and 13C nmr, UV–Vis spectra, melting point and solubility. Antimicrobial activities of the ligands and their complexes were tested against four bacteria (Staphylococcus aureus, Streptococcus faecalis Escherichia coli, Salmonella paratyphimurium) and a fungus (Candida albican). The molar conductance values indicate that they are 1:1 and 1:2 type electrolytes while the elemental analyses of the complexes reveals a 1:1 metal to ligand stoichiometry. The relevant IR bands suggest coordination is through the C=N, C=O, N=C–O and C–N groups. Both 1H and 13C nmr corroborated the elemental analysis while the UV–Vis reveals intra-ligand charge transfer while the complexes exhibited the expected metal transitions bands. A proposed octahedral geometry is supported by spectral data. Only 1, 8-dichloroacridonehydrazone hydrochloride ligand was found to be active against all the organisms. Cobalt and nickel complexes of 1,8-dichloroacridonehydrazone hydrochloride were active against S. paratyphimurium and S. aureus, respectively, while cobalt complex of 1-chloropilocarpinenitrate-3-chlorophenylhydrazone was active against S. faecalis and S. paratyphimurium. The minimum inhibitory concentrations (MIC) were also recorded.

In vitro anti-proliferative activity of selected nutraceutical compounds in human cancer cell lines

Objective

We investigated the anti-proliferative or cytotoxic activities of five nutraceutical compounds: allyl isothiocyanate, β-carotene, caffeine, capsaicin, and lupanine that we consume respectively, for example, from mustard seeds, carrot, coffee, pepper, and lupin seeds against cancer cell lines (human colon: HCT 116 p53 wild type, HCT 116 p53−/− and lymphoblastic: CEM/CCRF, CEM/ADR5000).

Result

Out of the five compounds tested in vitro, capsaicin and β-carotene were more cytotoxic than the other three compounds against the four cancer cell lines. The most potent nutraceutical compound was capsaicin and it exerted its highest cytotoxicity against HCT 116 p53−/− with IC₅₀ value of 19.67 ± 0.06 µM. It is worth considering capsaicin for further development of anticancer drug against both colon and leukemia cancer types.

Cytotoxic Activity of Christia vespertilionis Root and Leaf Extracts and Fractions against Breast Cancer Cell Lines

Christia vespertilionis, commonly known as 'Daun Rerama', has recently garnered attention from numerous sources in Malaysia as an alternative treatment. Its herbal decoction was believed to show anti-inflammatory and anti-cancer effects. The present study investigated the cytotoxicity of the extract of root and leaf of C. vespertilionis. The plant parts were successively extracted using the solvent maceration method. The most active extract was further fractionated to afford F1-F8. The cytotoxic effects were determined using MTT assay against human breast carcinoma cell lines (MCF-7 and MDA-MB-231). The total phenolic content (TPC) of the extracts were determined. The antioxidant properties of the extract were also studied using DPPH and β-carotene bleaching assays. The ethyl acetate root extract demonstrated selective cytotoxicity especially against MDA-MB-231 with the highest TPC and antioxidant properties compared to others (p < 0.05). The TPC and antioxidant results suggest the contribution of phenolic compounds toward its antioxidant strength leading to significant cytotoxicity. F3 showed potent cytotoxic effects while F4 showed better antioxidative strength compared to others (p < 0.05). Qualitative phytochemical screening of the most active fraction, F3, suggested the presence of flavonoids, coumarins and quinones to be responsible toward the cytotoxicity. The study showed the root extracts of C. vespertilionis to possess notable anti-breast cancer effects.

Repurposing of drugs: An attractive pharmacological strategy for cancer therapeutics

Human malignancies are one of the major health-related issues though out the world and anticipated to rise in the future. The development of novel drugs/agents requires a huge amount of cost and time that represents a major challenge for drug discovery. In the last three decades, the number of FDA approved drugs has dropped down and this led to increasing interest in drug reposition or repurposing. The present review focuses on recent concepts and therapeutic opportunities for the utilization of antidiabetics, antibiotics, antifungal, anti-inflammatory, antipsychotic, PDE inhibitors and estrogen receptor antagonist, Antabuse, antiparasitic and cardiovascular agents/drugs as an alternative approach against human malignancies. The repurposing of approved non-cancerous drugs is an effective strategy to develop new therapeutic options for the treatment of cancer patients at an affordable cost in clinics. In the current scenario, most of the countries throughout the globe are unable to meet the medical needs of cancer patients because of the high cost of the available cancerous drugs. Some of these drugs displayed potential anti-cancer activity in preclinic and clinical studies by regulating several key molecular mechanisms and oncogenic pathways in human malignancies. The emerging pieces of evidence indicate that repurposing of drugs is crucial to the faster and cheaper discovery of anti-cancerous drugs.

Cytotoxicity of eupatorin in MCF-7 and MDA-MB-231 human breast cancer cells via cell cycle arrest, anti-angiogenesis and induction of apoptosis

Eupatorin has been reported with in vitro cytotoxic effect on several human cancer cells. However, reports on the mode of action and detail mechanism of eupatorin in vitro in breast cancer disease are limited. Hence, eupatorin's effect on the human breast carcinoma cell line MCF-7 and MDA-MB-231 was investigated. MTT assay showed that eupatorin had cytotoxic effects on MCF-7 and MDA-MB-231 cells but was non-toxic to the normal cells of MCF-10a in a time-dose dependent manner. At 24 h, the eupatorin showed mild cytotoxicity on both MCF-7 and MDA-MB-231 cells with IC50 values higher than 20 μg/mL. After 48 h, eupatorin at 5 μg/mL inhibited the proliferation of MCF-7 and MDA-MB-231 cells by 50% while the IC50 of MCF-10a was significantly (p < 0.05) high with 30 μg/mL. The concentration of eupatorin at 5 μg/mL induced apoptosis mainly through intrinsic pathway by facilitating higher fold of caspase 9 compared to caspase 8 at 48 h. The cell cycle profile also showed that eupatorin (5 μg/mL) exerted anti-proliferation activity with the cell cycle arrest of MCF-7 and MDA-MB-231 cells at sub Gθ/G1 in a time-dependent manner. In addition, wound healing assay showed an incomplete wound closure of scratched MDA-MB-231 cells, and more than 60% of the MDA-MB-231 cells were prevented to migrate and invade the membrane in the Boyden chamber after 24 h. Eupatorin also inhibited angiogenic sprouting of new blood vessels in ex vivo mouse aorta ring assay. In gene expression assay, eupatorin up-regulated pro-apoptotic genes such as Bak1, HIF1A, Bax, Bad, cytochrome c and SMAC/Diablo and blocked the Phospho-Akt pathway. In conclusion, eupatorin is a potent candidate to induce apoptosis and concurrently inhibit the invasion, migration and angiogenesis of MDA-MB-231 and MCF-7 cells through inhibition of Phospho-Akt pathway and cell cycle blockade.

Antioxidant and cytotoxic activity of new di- and polyamine caffeine analogues

A series of new di- and polyamine-caffeine analogues were synthesised and characterised by NMR, FT-IR, and MS spectroscopic methods. To access the stability of the investigated caffeine analogues, molecular dynamic simulations were performed in NAMD 2.9 assuming CHARMM36 force field. To evaluate the antioxidant capacity of new compounds, three different antioxidant assays were used, namely 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH^•) scavenging activity, ferrous ions (Fe²⁺) chelating activity, and Fe³⁺→Fe²⁺reducing ability. In vitro, the ability of new derivatives to protect human erythrocytes against oxidative haemolysis induced by free radical from 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH) was estimated. The cytotoxic activity was tested using MCF-7 breast cancer cells and human erythrocytes. All compounds showed the antioxidant capacity depending mostly on their ferrous ions chelating activity. In the presence of AAPH, some derivatives were able to effectively inhibit the oxidative haemolysis. Two derivatives, namely 8-(methyl(2-(methylamino)ethyl)-amino)caffeine and 8-(methyl(3-(methylamino)propyl)amino)caffeine, showed cytotoxic activity against MCF-7 breast cancer cells but not against human erythrocytes. Therefore, it is concluded that the selected di- and polyamine caffeine analogues, depending on their chemical structure, were able to minimise the oxidative stress and to inhibit the tumour cell growth. The confirmed antioxidant and cytotoxic properties of some caffeine derivatives make them attractive for potential applications in food or pharmaceutical industries.

Non-covalent interactions between thio-caffeine derivatives and water-soluble porphyrin in ethanol-water environment

To determine the binding interactions and ability to form the non-covalent systems, the association process between 5,10,15,20-tetrakis[4-(trimethylammonio)phenyl]-21H,23H-porphine tetra-p-tosylate (H₂TTMePP) and a series of five structurally diverse thio-caffeine analogues has been studied in ethanol and ethanol-water solutions, analyzing its absorption and steady-state fluorescence spectra. The porphyrin fluorescence lifetimes in the systems studied were established as well. During the titration with thio-caffeine compounds the slight bathochromic effect and considerable hypochromicity of the porphyrin Soret band maximum can be noted. The fluorescence quenching effect observed for interactions in H₂TTMePP - thio-caffeine derivative systems, as well as the order of binding and fluorescence quenching constants (of 10⁵-10³mol^-1) suggest the existence of the mechanism of static quenching due to the formation of non-covalent and non-fluorescent stacking complexes. In all the systems studied the phenomenon of the fractional accessibility of the fluorophore for the quencher was observed as well. Additionally, the specific binding interactions, due to the changes in reaction environment polarity, can be observed. It was found that thio-caffeine compounds can quench the porphyrin fluorescence according to the structure of thio-substituent in caffeine molecule. The obtained results can be potentially useful from scientific, therapeutic or environmental points of view.

Metallomics for Alzheimer's disease treatment: Use of new generation of chelators combining metal-cation binding and transport properties

Alzheimer's disease (AD) is a progressive neurodegenerative disorder affecting tens of million people. Currently marketed drugs have limited therapeutic efficacy and only slowing down the neurodegenerative process. Interestingly, it has been suggested that biometal cations in the amyloid beta (Aβ) aggregate deposits contribute to neurotoxicity and degenerative changes in AD. Thus, chelation therapy could represent novel mode of therapeutic intervention. Here we describe the features of chelators with therapeutically relevant mechanism of action. We have found that the tested compounds effectively reduce the toxicity of exogenous Aβ and suppress its endogenous production as well as decrease oxidative stress. Cholyl hydrazones were found to be the most active compounds. In summary, our data show that cation complexation, together with improving transport efficacy may represent basis for eventual treatment strategy in AD.

Triterpenic azines, a new class of compounds with selective cytotoxicity to leukemia cells CCRF-CEM

Aim: From betulinic acid (1a), we synthesized 30-oxobetulinic acid (2a) that is highly cytotoxic against many cancer cell lines; however, its generic toxicity is the main obstacle in further development as cytostatic. Methodology & results: From 2a, we prepared a new class of compounds – nonsymmetrical azines and tested their in vitro cytotoxicity. All new azines with a free 28-COOH group (4a–4e) were highly and selectively cytotoxic against the T-lymphoblastic leukemia cell line CCRF-CEM and exhibited dose-dependent inhibition of RNA and DNA synthesis and other cell-cycle alterations, including the M-phase block. Conclusion: The potential use of azines (4a–4e) in drug development focused on hematological cancers is significantly higher than that of previously studied acids 1a and 2a.

Synthesis and antitumor evaluation of hybrids of 5,8-dioxo-5,8-dihydroisoquinoline-4-carboxylates and carbohydrates

Aim: Cancer has emerged as a growing public health problem in many parts of the world. Methodology: We describe the synthesis of a series of carbohydrate-based isoquinoline-5,8-diones through the 1,4-addition reaction between 5,8-dioxo-5,8-dihydroisoquinoline and aminocarbohydrates. Halogenated quinones were also synthesized. Their inhibitory effects on the proliferation of human cancer cell lines were studied. Results & conclusion: The most promising compound, derived from isoquinoline-5,8-dione, containing ribofuranosidyl ring, was selectively active in vitro against H1299 cancer cells, with 1.7-fold higher activity than that of vinorelbine tartrate. This result suggests that the glycoconjugate in question may constitute a valuable lead compound to design and synthesize a more active and less toxic derivative with respect to the development of a new antitumor substance.

New N-substituted hydrazones, derivatives of uridyl aldehyde

N-substituted isomeric hydrazones of uridyl aldehyde have been synthesized. The occurrence of the dominant E isomers with respect to the azomethine group was confirmed by means of NMR spectroscopy. Synthesized hydrazones feature an acetonide moiety as a protection of two hydroxyl groups on the ribose part. The attempt to remove the protecting group resulted in an azo-hydrazone tautomeric mixture. The described compounds may be valuable chiral ligands for metal chelation. Assessment of manganese(II) ion affinity to one selected hydrazone was performed.

Design and synthesis of some novel 4-Chloro-N-(4-(1-(2-(2-cyanoacetyl)hydrazono)ethyl)phenyl) benzenesulfonamide derivatives as anticancer and radiosensitizing agents

A novel series of sulfonamide derivatives 4-21 have been synthesized starting from the strategic starting material (E)-4-Chloro-N-(4-(1-(2-(2-cyanoacetyl)hydrazono)ethyl)phenyl) benzenesulfonamide 4. Two series of hydrazone 5-9, and pyridone 10-21 derivatives bearing a sulfonamide moiety were obtained. All the newly synthesized compounds were evaluated for their in vitro cytotoxic activity against human liver cancer cell line (HepG2). Compounds 4-6, 8, 9, 10-14 and 16-18 showed higher activity compared to doxorubicin as a positive control. The radiosensitizing ability of the most promising compounds 4, 10 and 12 was studied which showed an increase in the cell killing effect of γ-radiation after combination with these derivatives. The molecular design was performed to predict the binding mode of the most promising compounds 4, 10 and 12 with the active site of hCA IX, that showed appropriate fitting with the relevant amino acids in the binding pocket on the basis of standard bond lengths, angles, S score and E conformation data.

Design, Synthesis and Evaluation of Antiproliferative Activity of New Benzimidazolehydrazones

The synthesis and antiproliferative activity of new benzimidazole derivatives bearing an hydrazone mojety at the 2-position is described. The new N′-(4-arylidene)-1H-benzo[d]imidazole-2-carbohydrazides were evaluated for their cytostatic activity toward the murine leukemia (L1210), human T-cell leukemia (CEM), human cervix carcinoma (HeLa) and human pancreas carcinoma cells (Mia Paca-2). A preliminary structure-activity relationship could be defined. Some of the compounds possess encouraging and consistent antiproliferative activity, having IC₅₀ values in the low micromolar range.

Development of Hg2+ sensor based on N′-[1-(pyridin-2-yl)ethylidene]benzenesulfono-hydrazide (PEBSH) fabricated silver electrode for environmental remediation

N′-[1-(Pyridin-2-yl)ethylidene]benzenesulfonohydrazide (PEBSH) was synthesized via a simple condensation of 2-acetyl pyridine and benzene sulfonyl hydrazide in very good yield and crystallized, and then used in the formation of a Hg²⁺ sensor.