Design, synthesis and identification of novel molecular hybrids based on naphthoquinone aromatic hydrazides as potential trypanocide and leishmanicidal agents.

In pursuit of potential agents to treat Chagas disease and leishmaniasis, we report the design, synthesis, and identification novel naphthoquinone hydrazide-based molecular hybrids. The compounds were subjected to in vitro trypanocide and leishmanicidal activities. N'-(1,4-Dioxo-1,4-dihydronaphthalen-2-yl)-3,5-dimethoxybenzohydrazide (13) showed the best performance against Trypanosoma cruzi (IC50 1.83 µM) and Leishmania amazonensis (IC50 9.65 µM). 4-Bromo-N'-(1,4-dioxo-1,4-dihydronaphthalen-2-yl)benzohydrazide (16) exhibited leishmanicidal activity (IC50 12.16 µM). Regarding trypanocide activity, compound 13 was low cytotoxic to LLC-MK2 cells (SI = 95.28). Furthermore, through molecular modeling studies, the cysteine proteases cruzain, rhodesain and CPB2.8 were identified as the potential biological targets.

Vanadium(V) complexes derived from triphenylphosphonium and hydrazides: cytotoxicity evaluation and interaction with biomolecules.

The development of coordination compounds with antineoplastic therapeutic properties is currently focused on non-covalent interactions with deoxyribonucleic acid (DNA). Additionally, the interaction profiles of these compounds with globular plasma proteins, particularly serum albumin, warrant thorough evaluation. In this study, we report on the interactions between biomolecules and complexes featuring hydrazone-type imine ligands coordinated with vanadium. The potential to enhance the therapeutic efficiency of these compounds through mitochondrial targeting is explored. This targeting is facilitated by the derivatization of ligands with triphenylphosphonium groups. Thus, this work presents the synthesis, characterization, interactions, and cytotoxicity of dioxidovanadium(V) complexes (C1-C5) with a triphenylphosphonium moiety. These VV-species are coordinated to hydrazone-type iminic ligands derived from (3-formyl-4-hydroxybenzyl)triphenylphosphonium chloride ([AH]Cl) and aromatic hydrazides ([H2L1]Cl-[H2L5]Cl). The structures of the five complexes were elucidated through single-crystal X-ray diffraction and vibrational spectroscopies, confirming the presence of dioxidovanadium(V) species in various geometries with degrees of distortion (τ = 0.03-0.50) and highlighting their zwitterionic characteristics. The molecular structural stability of C1-C5 in solution was ascertained using 1H, 19F, 31P, and 51V-nuclear magnetic resonance. Moreover, their interactions with biomolecules were evaluated using diverse spectroscopic methodologies and molecular docking, indicating moderate interactions (Kb ≈ 104 M-1) with calf thymus DNA in the minor groove and with human serum albumin, predominantly in the superficial IB subdomain. Lastly, the cytotoxic potentials of these complexes were assessed in keratinocytes of the HaCaT lineage, revealing that C1-C5 induce a reduction in metabolic activity and cell viability through apoptotic pathways.

Interaction with CT-DNA and in vitro cytotoxicity of two new copper(II)-based potential drugs derived from octanoic hydrazide ligands.

Two copper(II) complexes [Cu(Hpmoh)(NO3)(NCS)] (1) and [Cu(peoh)(N3)]2 (2) were designed and synthesized by reaction of Cu(NO3)2·3H2O with hydrazone Schiff base ligands,abbreviated with Hpmoh and Hpeoh. Hpmoh and Hpeoh were prepared by condensation reaction of octanoic hydrazide with pyridine-2-carboxyaldehyde and 2-acetylpyridine, respectively. Complexes 1 and 2 were characterized using different analytical techniques such as FT-IR, UV-Vis, IR, EPR and single X-ray diffraction (XRD) analyses as well as computational methods (DFT). The XRD of 1 and 2 shows a mononuclear or a dinuclear structure with the copper(II) centre adopting a slightly distorted square pyramidal geometry. In water-containing solution and in DMSO, 1 and 2 undergo a partial transformation with formation of [Cu(Hpmoh)(NO3)(NCS)] (1) and [Cu(Hpmoh)(NO3)(H2O/DMSO)] (1a) in one system and [Cu(peoh)(N3)] (2a) in the other one, as supported by DFT calculations. Docking simulations confirmed that the intercalation is the preferred binding mode with DNA for 1, 1a and 2a, but suggested that the minor groove binding is also possible. A significant fluorescence quenching of the DNA-ethidium bromide conjugate was observed upon the addition of complexes 1 and 2 with a quenching constant around 104 M-1 s-1. Finally, both 1 and 2 were examined for anti-cancer activity using MDA-MB-231 (human breast adenocarcinoma) and A375 (malignant melanoma) cell lines through in vitro MTT assay which suggest comparable cancer cell killing efficacy, with the higher effectiveness of 2 due to the dissociation into two [Cu(peoh)(N3)] units.

Phenothiazine-based fluorescent probes for the detection of hydrazine in environment and living cells.

As an important chemical raw material, hydrazine brings convenience to people's lives and provides opportunities for human development. However, the misuse or leakage of hydrazine has brought pollution to the environment, including water, soil and living organisms. At the same time, hydrazine poses a potential threat to human health as a carcinogen. Despite the enormous challenges, it is crucial to develop an effective method to detect hydrazine in environmental samples. In this work, we have synthesized a series of probes based on phenothiazine fluorophore by the introduction of different substituents and developed a novel probe for the detection of hydrazine. The probe is capable of detecting hydrazine in aqueous solutions with high sensitivity and selectivity, and can be easily fabricated into paper test strips for use in in situ samples. In addition, the probe is effective in detecting hydrazine in water, soil, cells, and zebrafish, providing an excellent tool for detecting hydrazine in the environment.

Design, Synthesis, and In Vitro and In Vivo Bioactivity Studies of Hydrazide-Hydrazones of 2,4-Dihydroxybenzoic Acid.

In this research, twenty-four hydrazide-hydrazones of 2,4-dihydroxybenzoic acid were designed, synthesized, and subjected to in vitro and in vivo bioactivity studies. The chemical structure of the obtained compounds was confirmed by spectral methods. Antimicrobial activity screening was performed against a panel of microorganisms for all synthesized hydrazide-hydrazones. The performed assays revealed the interesting antibacterial activity of a few substances against Gram-positive bacterial strains including MRSA-Staphylococcus aureus ATCC 43300 (compound 18: 2,4-dihydroxy-N-[(2-hydroxy-3,5-diiodophenyl)methylidene]benzohydrazide-Minimal Inhibitory Concentration, MIC = 3.91 µg/mL). In addition, we performed the in vitro screening of antiproliferative activity and also assessed the acute toxicity of six hydrazide-hydrazones. The following human cancer cell lines were used: 769-P, HepG2, H1563, and LN-229, and the viability of the cells was assessed using the MTT method. The HEK-293 cell line was used as a reference line. The toxicity was tested in vivo on Danio rerio embryos using the Fish Embryo Acute Toxicity (FET) test procedure according to OECD No. 236. The inhibitory concentration values obtained in the in vitro test showed that N-[(4-nitrophenyl)methylidene]-2,4-dihydroxybenzhydrazide (21) inhibited cancer cell proliferation the most, with an extremely low IC50 (Inhibitory Concentration) value, estimated at 0.77 µM for LN-229. In addition, each of the compounds tested was selective against cancer cell lines. The compounds with a nitrophenyl substituent were the most promising in terms of inhibition cancer cell proliferation. The toxicity against zebrafish embryos and larvae was also very low or moderate.

Biological Effects and Crystal X-Ray Study of Novel Schiff Base Containing Pentafluorophenyl Hydrazine: In Vitro and in Silico Studies.

A novel Schiff base namely 3,5-di-tert-butyl-6-((2-(perfluorophenyl)hydrazono)methyl)phenol was successfully synthesized and characterized using FT-IR and 1 H-NMR, 13 C-NMR, and 19 F-NMR. The crystal structure analysis of the Schiff base compound was also characterized with single crystal X-ray diffraction studies and supported the spectroscopic results. The cytotoxicity, anti-bacterial properties, and enzyme inhibition of the compound were also investigated. The molecular docking studies were performed in order to explain the interactions of the synthesized compound with target enzymes. The newly synthesized hydrazone derivative Schiff base compound showed high cellular toxicity on MCF-7 and PC-3 cells. Also, this compound caused low antibacterial effect on E. coli and S. aureus. Besides, the compound exhibited the inhibitory effect against pancreatic cholesterol esterase and carbonic anhydrase isoenzyme I, II with IC50 values 63, 99, and 188 µM, respectively. Consequently, it has been determined that the prepared Schiff base is an active compound in terms of cytotoxicity, enzyme inhibition, and anti-bacterial properties. These results provide preliminary information for some biological features of the compound and can play a major role in drug applications of the Schiff base compound.

Injectable, self-healing hydrogel adhesives with firm tissue adhesion and on-demand biodegradation for sutureless wound closure.

Tissue adhesives have garnered extensive interest as alternatives and supplements to sutures, whereas major challenges still remain, including weak tissue adhesion, inadequate biocompatibility, and uncontrolled biodegradation. Here, injectable and biocompatible hydrogel adhesives are developed via catalyst-free o-phthalaldehyde/amine (hydrazide) cross-linking reaction. The hydrogels demonstrate rapid and firm adhesion to various tissues, and an o-phthalaldehyde-mediated tissue adhesion mechanism is established. The hydrogel adhesives show controlled degradation profiles of 6 to 22 weeks in vivo through the incorporation of disulfide bonds into hydrogel network. In liver and blood vessel injury, the hydrogels effectively seal the incisions and rapidly stop bleeding. In rat and rabbit models of full-thickness skin incision, the hydrogel adhesives quickly close the incisions and accelerate wound healing, which exhibit efficacies superior to those of commercially available fibrin glue and cyanoacrylate glue. Thus, the hydrogel adhesives show great potential for sutureless wound closure, hemostasis sealing, and prevention of leakage in surgical applications.

A Comprehensive Investigation of Hydrazide and Its Derived Structures in the Agricultural Fungicidal Field.

Hydrazides are present in many bioactive molecules and exhibit a variety of biological activities, such as insecticidal, herbicidal, antifungal, antitumor, and antiviral effects. In this Review, we review the application of hydrazide and its derived structures in the agricultural fungicidal field, including monohydrazides, diacylhydrazines, hydrazide-hydrazones, and sulfonyl hydrazides. In addition, the antifungal mechanism of action of the hydrazide derivatives was analyzed and summarized, mainly involving succinate dehydrogenase inhibitors, laccase inhibitors, and targeting plasma membranes. Finally, based on the structural analysis of the novel fungicidal lead compounds, the structure-activity relationship of the hydrazide derivatives was constructed and the development trend of hydrazide structures in fungicidal applications was prospected. It is hoped that this Review can provide some significant guidance for the development of new hydrazide fungicides in the future.

Switching to a 'turn-on' fluorescent probe for rapid detection of hydrazine in human breast cancer cells using a test-strip.

A fluorescent probe TPSBT was developed to monitor hydrazine detection with a "turn on" response, converting from a "non-responsive" probe by a simple structural modification. The probe shows very weak fluorescence due to the strong ICT process and upon treatment with hydrazine, green fluorescence appears due to the blocking of this ICT by the formation of a hydrazone. The probe TPSBT can detect hydrazine with a very low detection limit (1.22 × 10-7 M) and within a very short time period of 50 s. Additionally, the probe is able to give a response in live cell imaging (MDA-MB 231) and also in the solid phase.

Robust ERα-Targeted Near-Infrared Fluorescence Probe for Selective Hydrazine Imaging in Breast Cancer.

Breast cancer is the most common malignancy in women and may become worse when a high concentration of hydrazine is absorbed from the environment or drug metabolite. Therefore, rapid and sensitive detection of hydrazine in vivo is beneficial for people's health. In this work, a novel estrogen receptor α (ERα)-targeted near-infrared fluorescence probe was designed to detect hydrazine levels. The probe showed good ERα affinity and an excellent fluorescence response toward hydrazine. Selectivity experiments demonstrated that the probe had a strong anti-interference ability. Mechanistic studies, including mass spectrometry (MS) and density functional theory (DFT) calculation, indicated that intermolecular charge transfer (ICT) progress was hindered when the probe reacted with hydrazine, resulting in fluorescent quenching. In addition, the probe could selectively bind to MCF-7 breast cancer cells with excellent biocompatibility. The in vivo and ex vivo imaging studies demonstrated that the probe could rapidly visualize hydrazine with high contrast in MCF-7 xenograft tumors. Therefore, this probe can serve as a potential tool to robustly monitor hydrazine levels in vivo.

A dual-ratiometric mitochondria-targeted fluorescent probe to detect hydrazine in soil samples and biological imaging.

Hydrazine (N2H4) is carcinogenic, extremely toxic, and induces serious environmental contamination and physiological dysfunction; however, it is widely used as an industrial material. Hence, the development of a simple and effective analytical method to detect N2H4 detection in both environmental and biological sectors is warranted. In this work, an intramolecular charge transfer (ICT)-based fluorescent probe 1, namely (Z)- 1-(4-acetoxybenzyl)- 4-(1-cyano-2-(7-(diethylamino)- 2-oxo-2 H-chromen-3-yl)vinyl)pyridin-1-ium, was designed for dual-excitation (420 and 600 nm, excitation separations >160 nm), near infrared (NIR)-emissive, and ratiometric fluorescent detection of N2H4. The sensing behavior of probe 1 for N2H4 detection was shown to be available over a wide pH range, and detection limits of 68 nM and 569 nM were achieved at excitation wavelengths of 420 and 600 nm, respectively. In addition, probe 1 was successfully used to image mitochondrial N2H4 in living cells and zebrafish. Furthermore, the probe was also capable of determining hydrazine signals in test strips and environmental soil.

Copper-Catalyzed Phosphorylation of N,N-Disubstituted Hydrazines: Synthesis of Multisubstituted Phosphorylhydrazides as Potential Anticancer Agents.

An efficient copper-catalyzed aerobic oxidative cross-dehydrogenative coupling reaction for the synthesis of multisubstituted phosphorylhydrazides from N,N-disubstituted hydrazines and hydrogen phosphoryl compounds is accomplished. The reaction proceeds under mild conditions without the addition of any external oxidants and bases. This work reported here represents a direct P(═O)-N-N bond formation with the advantages of being operationally simple, good functional group tolerance, and high atom and step economy. Furthermore, the selected compounds exhibit potential inhibitory activity against tumor cells, which can be used in the field of screening of anticancer agents as new chemical entities.

Highly potent inhibitors of cathepsin K with a differently positioned cyanohydrazide warhead: structural analysis of binding mode to mature and zymogen-like enzymes.

Cathepsin K (CatK) is a target for the treatment of osteoporosis, arthritis, and bone metastasis. Peptidomimetics with a cyanohydrazide warhead represent a new class of highly potent CatK inhibitors; however, their binding mechanism is unknown. We investigated two model cyanohydrazide inhibitors with differently positioned warheads: an azadipeptide nitrile Gü1303 and a 3-cyano-3-aza-ß-amino acid Gü2602. Crystal structures of their covalent complexes were determined with mature CatK as well as a zymogen-like activation intermediate of CatK. Binding mode analysis, together with quantum chemical calculations, revealed that the extraordinary picomolar potency of Gü2602 is entropically favoured by its conformational flexibility at the nonprimed-primed subsites boundary. Furthermore, we demonstrated by live cell imaging that cyanohydrazides effectively target mature CatK in osteosarcoma cells. Cyanohydrazides also suppressed the maturation of CatK by inhibiting the autoactivation of the CatK zymogen. Our results provide structural insights for the rational design of cyanohydrazide inhibitors of CatK as potential drugs.

Selective elimination of pluripotent stem cells by PIKfyve specific inhibitors.

Inhibition of PIKfyve phosphoinositide kinase selectively kills autophagy-dependent cancer cells by disrupting lysosome homeostasis. Here, we show that PIKfyve inhibitors can also selectively eliminate pluripotent embryonal carcinoma cells (ECCs), embryonic stem cells, and induced pluripotent stem cells under conditions where differentiated cells remain viable. PIKfyve inhibitors prevented lysosome fission, induced autophagosome accumulation, and reduced cell proliferation in both pluripotent and differentiated cells, but they induced death only in pluripotent cells. The ability of PIKfyve inhibitors to distinguish between pluripotent and differentiated cells was confirmed with xenografts derived from ECCs. Pretreatment of ECCs with the PIKfyve specific inhibitor WX8 suppressed their ability to form teratocarcinomas in mice, and intraperitoneal injections of WX8 into mice harboring teratocarcinoma xenografts selectively eliminated pluripotent cells. Differentiated cells continued to proliferate, but at a reduced rate. These results provide a proof of principle that PIKfyve specific inhibitors can selectively eliminate pluripotent stem cells in vivo as well as in vitro.

Reaction-based fluorescent and chemiluminescent probes for formaldehyde detection and imaging.

Formaldehyde (FA), a reactive carbonyl species, is classified as Group 1 carcinogen by International Agency for Research on Cancer (IARC) in 2004. In addition, clinical studies have implicated that elevated levels of FA have been associated with different kinds of diseases, such as neurodegenerative diseases, diabetes, and chronic liver and heart disorders. However, in addition to the direct inhalation of FA in the environment, most organisms can also produce FA endogenously by demethylases and oxidases during the metabolism of amino acids and xenobiotics. Since FA plays an important role in physiological and pathological processes, developing reliable and efficient methods to monitor FA levels in biological samples is crucial. Reaction-based fluorescent/chemiluminescent probes have provided robust methods for FA detection and real-time visualization in living organisms. In this highlight, we will summarize the major developments in the structure design and applications of FA probes in recent years. Three main strategies for designing FA probes have been discussed and grouped by different reaction mechanisms. In addition, some miscellaneous reaction mechanisms have also been discussed. We also highlight novel applications of these probes in biological systems, which offer powerful tools to discover the diverse functions of FA in physiology and pathology processes.

EGPI-1, a novel eIF4E/eIF4G interaction inhibitor, inhibits lung cancer cell growth and angiogenesis through Ras/MNK/ERK/eIF4E signaling pathway.

eIF4E plays an important role in regulating tumor growth and angiogenesis, and eIF4E is highly expressed in a variety of lung cancer cell lines. siRNA eIF4E can significantly inhibit the proliferation of lung cancer cells, indicating that inhibition of eIF4E may become a novel anti-tumor target. In the previous study, we synthesized a series of small molecule compounds with the potential to inhibit eIF4E. Among them, the compound EGPI-1 significantly inhibited the proliferation of a variety of lung cancer cells such as A549, NCI-H460, NCI-H1650 and 95D without inhibiting the proliferation of HUVEC cells. Further studies found that EGPI-1 interfered with the eIF4E/eIF4G interaction and inhibited the phosphorylation of eIF4E in NCI-H460 cells. The results of flow cytometry showed that EGPI-1 induced apoptosis and G0/G1 cycle arrest in NCI-H460 cell. Interestingly, we also found that EGPI-1 induced autophagy and DNA damage in NCI-H460 cells. The mechanism results showed that EGPI-1 inhibited the Ras/MNK/ERK/eIF4E signaling pathway. Moreover, EGPI-1 inhibited tube formation of HUVECs, as well as inhibited the neovascularization of CAM, proving the anti-angiogenesis activity of EGPI-1. The NCI-H460 xenograft studies showed that EGPI-1 inhibited tumor growth and angiogenesis in vivo by regulating Ras/MNK/ERK/eIF4E pathway. Our studies proved that eIF4E was a novel target for regulating tumor growth, and the eIF4E/eIF4G interaction inhibitor EGPI-1 was promising to develop into a novel anti-lung cancer drug.

Novel 1,3,5-triazine-nicotinohydrazide derivatives induce cell arrest and apoptosis in osteosarcoma cancer cells and inhibit osteosarcoma in a patient-derived orthotopic xenograft mouse model.

The present study deals with developing novel 1,3,5-triazine-nicotinohydrazide derivatives as potent CDK9 inhibitors in a straightforward synthetic route with potent anti-osteosarcoma activity. The most potent CDK9 inhibitor compound 5k inhibits proliferation of MG-63 cells via induction of apoptosis and G2/M cell cycle arrest. It reduces tumor progression in the patient-derived orthotopic xenograft (PDOX) mouse model with significant antioxidant and anti-inflammatory activity. In tumor tissue homogenates, it caused significant inhibition of CDK9 and inhibited the phosphorylation of RNAPII ser2 and reduced MCL-1 expression in Western blot analysis. Compound 5k also showed considerable bioavailability in SD mice. Our results demonstrated that compound 5k inhibits growth of OS in vitro and in vivo via inhibition of CDK9 which attenuated the downstream phosphorylation of RNAPII ser2 and represses expression of the anti-apoptotic protein, MCL-1 for the induction of apoptosis in OS.

Potent Hydrazide-Based HDAC Inhibitors with a Superior Pharmacokinetic Profile for Efficient Treatment of Acute Myeloid Leukemia In Vivo.

As "Michael acceptors" may induce promiscuous responses in mammalian cells by reacting with various proteins, we modified the cinnamamide of our previous hydrazide-based HDAC inhibitors (HDACIs) to deactivate the Michael reaction. Representative compound 11h is 2-5 times more potent than lead compound 17 in both HDAC inhibitory activity (IC50 = 0.43-3.01 nM) and cell-based antitumor assay (IC50 = 19.23-61.04 nM). The breakthrough in the pharmacokinetic profile of 11h (oral bioavailability: 112%) makes it a lead-in-class oral active agent, validated in the in vivo anti-AML study (4 mg/kg p.o., TGI = 78.9%). Accumulated AcHH3 and AcHH4 levels in tumor tissue directly correlate with the in vivo efficacy, as panobinostat with lower AcHH3 and AcHH4 levels than 11h displays limited activity. To the best of our knowledge, this work contributes the first report of in vivo antitumor activity of hydrazide-based HDACIs. The outstanding pharmacokinetic/pharmacodynamic and antitumor activity of 11h could potentially extend the clinical application of current HDACIs.

Ultrasound promoted green synthesis, anticancer evaluation, and molecular docking studies of hydrazines: a pilot trial.

We reported herein an efficient, environmentally friendly synthesis of hydrazine carboxamides (6a-l) in a water-glycerol (6:4) solvent system using ultrasonic irradiation. Ultrasonicated reactions were found to be much faster and more productive than conventional synthesis. The prepared compounds (6a-l) were tested against nine panels of 60 cancer cell lines according to the National Cancer Institute (NCI US) protocol. N-(4-Chlorophenyl)-2-(2-oxoindolin-3-ylidene)hydrazine-1-carboxamide (6b) was discovered to be promising anticancer agents with higher sensitivity against CCRF-CEM, HOP-92, UO-31, RMPI-8226, HL-60(TB), and MDA-MB-468 with percent growth inhibitions (%GIs) of 143.44, 33.46, 33.21, 33.09, 29.81, and 29.55 respectively. Compounds (6a-l) tested showed greater anticancer activity than Imatinib, except for compound 6k. Compounds 6b and 6c were found to be lethal on the CCRF-CEM leukaemia cell line, with %GIs of 143.44 and 108.91, respectively. Furthermore, molecular docking analysis was performed to investigate ligand binding affinity at the active site of epidermal growth factor (EGFR).

The cleavage kinetics of hydrazide derivatives of isoniazid by HPLC-UV/DAD and its impact on activity against Mycobacterium tuberculosis.

Isoniazid is a first-line drug for the treatment of tuberculosis, a bacterial disease caused by Mycobacterium tuberculosis. Its terminal amino group is highly reactive, leading to significant metabolic deactivation, drug interactions and hepatotoxicity. It is speculated that the activity of isoniazid derivatives is, in part, related to the cleavage of the protecting group. Therefore, this study aimed to evaluate the cleavage characteristics of previously developed isoniazid derivatives through kinetic studies by high-performance liquid chromatography with ultraviolet-diode array detectio to establish a comparison between the rates of the process and the respective activities against M. tuberculosis. Chromatographic separations were performed on an XDB C18 column coupled to an XDB C18 precolumn. The mobile phase consisted of ultrapure water and acetonitrile in gradient mode. The flow rate was 1.0 mL/min, the injection volume was 20 µL, and the detection wavelengths were 230 nm (derivatives and isatins) and 270 nm (isoniazid). Incubation of derivatives was carried out for 5 days in 10 mmol/L phosphate buffer solution (pH 3.0, 7.4, 8.0) or in fetal bovine serum at 37 °C. The incubation reduced the concentration of the derivatives and led to the formation of isoniazid in a first-order kinetic reaction. Isoniazid formation was logarithmically correlated with the minimum inhibitory concentration of the derivatives. The results showed that higher cleavage rates are associated with greater activities against M. tuberculosis, providing important information for the development of future generations of isoniazid derivatives and for screening drug candidates for the treatment of tuberculosis.