Compounds 4h Research Articles

Novel Endoperoxide Steroid Derivatives Containing Thiazole Moiety as Potential Antitumor Agents: Design, Synthesis, and Cytotoxic Evaluation

As part of the search for new steroid substances with potential application in oncology, a series of endoperoxide steroid derivatives (7a-n) containing a thiazole system were synthesized and evaluated for their cytotoxicities in four tumor cell lines. Among them, compound 7h exhibited the most significant cytotoxic activity against HepG2 cells (IC50 = 4.54 μM), being more potent than ergosterol peroxide. Furthermore, 7h was able to promote apoptosis in HepG2 cells and decrease the mitochondrial membrane potential, accompanied by activating the expression of cytochrome c, caspase-9, caspase-3, and Bax, while Bcl-2 expression was suppressed. The molecular mechanism may refer to the mitochondrial apoptotic pathway. On the whole, the above results incentivize the further study of 7h derivatives as potent anticancer agents.

Synthesis of 2,3-dihydroquinazolin-4(1H)-one derivatives as potential inhibitors of TNF-α

'The anti-inflammatory activities of the 2,3-dihydroquinazolin-4(1H)-one derivatives along with results from our in silico predictions (this study) encouraged us to explore this class of compounds as potential inhibitors of TNF-α. Among all the molecules assessed in silico the best ranked molecules were identified with the order as 3h > 3p > 3l based on the estimated total energy. The compound 3h participated in a H-bond interaction through its C = O group of the quinazoline-4(1H)-one ring with TYR151 of chain A in addition to the interactions with all the critical TYR residues via its chloro group. The interesting docking results were also obtained for compound 3l and 3p. For the access of this class of fused N-heteroarenes we adopted the β-cyclodextrin (β-CD) catalyzed approach involving the cyclocondensation of 2-aminobenzamide with aldehydes / ketones in pure water. Various aromatic, aliphatic and heteroaromatic aldehydes (including the cinnamaldehyde) along with ketones were employed for this purpose to afford the corresponding product in good to excellent yield. The recovery and recycling of the catalyst β-CD was successful. The inexpensive and eco-friendly nature along with the simple product purification as well as good product yield are the key advantages of this approach. When examined in vitro the compound 3h, 3l and 3p with the inhibition > 70% emerged as the most active compounds in this series as predicted by in silico studies. According to the SAR (Structure Activity Relationship) the effectiveness of the C-2 aryl group was found to be in the order Ar = C6H4Cl-p > 4-pyridyl > C6H4OMe-p > C6H2(OMe)3-m,p > C6H4OH-p etc. whereas an heteroaryl or alkyl group at this position was found to be less effective or ineffective. In terms of IC50 values the compound 3h, 3l and 3p appeared as superior than the known inhibitor thalidomide though they were not better than rolipram. Being identified as preliminary hits these compounds are of further pharmacological interest.

Anti-inflammatory efficacy and relevant SAR investigations of novel chiral pyrazolo isoquinoline derivatives: Design, synthesis, in-vitro, in-vivo, and computational studies targeting iNOS

Isoquinoline alkaloids are a rich source of multimodal agents with distinctive structural specificity and various pharmacological activities. In the present report, we propose a combination of design, synthesis, computational study, primary in-vitro screening using the lipopolysaccharide (LPS)-induced RAW 264.7 cell line, and in-vivo evaluation in mice models as a novel approach to speed up anti-inflammatory drugs discovery. The nitric oxide (NO) inhibitory effect of new compounds revealed that all of them displayed the potent NO inhibitory ability in a dose-dependent manner with no obvious cytotoxicity. A series of the model compounds 7a, 7b, 7d, 7f, and 7g have been identified as the most promising, with IC50 values of 47.76 μM, 33.8 μM, 20.76 μM, 26.74 μM, and 47.8 μM respectively in LPS-induced RAW 264.7 cell line. Structure-activity relationship (SAR) studies on a range of derivatives aided in identifying key pharmacophores in the lead compound. Western blotting data of 7d identified that our synthesized compounds can down-regulate and suppress the expression of the key inflammatory enzyme, inducible nitric oxide synthase (iNOS). These results suggested that synthesized compounds may be potent anti-inflammatory agents, inhibiting the NO-release, in turn, iNOS inflammatory pathways. Furthermore, in-vivo anti-inflammatory detection via xylene-induced ear edema in mice revealed that these compounds could also inhibit swelling in mice, with model compound 7h showing an inhibition activity (64.4%) at a concentration of 10 mg/kg comparable to the reference drug celecoxib. Molecular docking results showed that shortlisted compounds (7b, 7c, 7d, 7e, and 7h) had a potential binding affinity for iNOS with low energies, with S-Score to be −7.57, −8.22, −7.35, −8.95, −9.94 kcal/mol, respectively. All results demonstrated that the newly synthesized chiral pyrazolo isoquinoline derivatives are highly potential anti-inflammatory agents.

Glyco-conjugation in 3-β-anhydroicaritine

A convenient method has been developed for the glycol-conjugation in 3-position of β-anhydroicaritine in a reasonable yield. The structure of the 3-glycosylated β-anhydroicaritine derivatives was confirmed to be correct by 1H NMR, 13C NMR and HRMS spectrum. These compounds are less soluble than icaritin, but more soluble than icariside II in CCl4. The screening results showed that compounds 12h, 12i and 12j had higher cytotoxicity to HepG2 and MCF-7 at a concentration of 50 μM.

Design, synthesis, antimicrobial activity, DFT, and molecular docking studies of pyridine-pyrazole-based dihydro-1,3,4-oxadiazoles against various bacterial and fungal targets.

Antimicrobial resistance which is increasing at an alarming rate is a severe public health issue worldwide. Hence, the development of novel antibiotics is an urgent need as microbes have developed resistance against available antibiotics. In search of novel antimicrobial agents, a convenient route for the preparation of substituted 3-(1-phenyl-3-(p-tolyl)-1H-pyrazol-4-yl)-1-(2-phenyl-5-(pyridin-3-yl)-1,3,4-oxadiazol-3(2H)-yl)prop-2-en-1-ones (6a-6o) has been adopted by using pyridine-3-carbohydrazide and various aromatic aldehydes. The newly synthesized compounds were characterized by using various spectral techniques, for example, IR, 1 H NMR, 13 C NMR, and mass spectroscopy. Synthesized hybrids were studied for in vitro antimicrobial potency against various bacterial and fungal strains. Antibacterial results revealed that compounds 6e, 6h, 6i, 6l, and 6m were found to be most active against bacterial strains as they showed minimum inhibitory concentration(MIC) value of 62.5 μg/mL while compounds 6d, 6e, and 6h showed MIC value of 200 μg/mL against Candidaalbicans. The quantum parameters that relate to the bioavailability of the compounds were computed, followed by docking with different bacterial and fungal targets like sortase A, dihydrofolate reductase, thymidylate kinase, gyrase B, sterol 14-alpha demethylase. The experimental and computational results are in good agreement.

Synthesis, biological evaluation, and molecular docking study of chromen-linked hydrazine carbothioamides as potent α-glucosidase inhibitors.

Inhibiting α-glucosidase is a reliable method for reducing blood sugar levels in diabetic individuals. Several novel chromen-linked hydrazine carbothioamide (3a-r) were designed and synthesized by condensation of chromone-3-carbaldehyde with a variety of substituted thiosemicarbazides. The structures of these new analogues were elucidated through various advanced spectroscopic techniques (1 H NMR, 13 C NMR, and ESI-MS). The resulted compounds were screened for α-glucosidase inhibitory potential and all the compounds (3a-r) exhibited potent inhibition of α-glucosidase with IC50 values ranging 0.29-53.70 µM. Among them compounds 3c, 3f, 3h, and 3r displayed the highest α-glucosidase inhibitor capability with IC50 values of 1.50, 1.28, 1.08, and 0.29 µM, respectively. Structure-activity relationship showed that different substituted groups are responsible for the variation in the α-glucosidase inhibition. The kinetics studies of the most active inhibitor (3r) were performed, to investigate the mode of inhibition and dissociation constants (Ki), that indicated a competitive inhibitor with Ki value of 1.47 ± 0.31 µM. Furthermore, molecular docking studies was performed to reveal the possible interactions, such as H-bonding, or π-π stacking, with the key residues of α-glucosidase. Docking analysis revealed the importance of hydrazine carbothioamide moiety of compounds in the attachment of ligands with the crucial residues of α-glucosidase. The estimated pharmacokinetic, physicochemical, and drug likeness properties of compounds 3a-r reflects that these molecules have acceptable range of these properties.

Semisynthesis, anti-oomycete and anti-fungal activities of ursolic acid ester derivatives

Using ursolic acid (UA) as the lead compound, thirteen UA ester derivatives (3 and 7a-l) were synthesized by modifying their C-3 and C-28 positions, respectively, and their structures were well characterized by 1H NMR, 13C NMR, HRMS and melting points. Furthermore, we evaluated the anti-oomycete and anti-fungal activities of these compounds against Phytophthora capsici and Fusarium graminearum in vitro. The results showed that compound 7h exhibited prominent anti-oomycete and anti-fungal activities, and the median effective concentration (EC50) values of 7h against P. capsici and F. graminearum were 70.49 and 113.21 mg/L, respectively. This study suggested that the anti-oomycete and anti-fungal activities of esters synthesized by introducing acyloxy group at C-3 position of UA was more conspicuous than that of esters synthesized by introducing benzyloxy group at C-28 position. This result will pave the way for further modification of UA to develop potential new fungicides.

Design, synthesis and biological evaluation of thiazole and imidazo[1,2-a]pyridine derivatives containing a hydrazone substructure as potential agrochemicals

Agricultural chemicals with multifunctional applications in crop protection have attracted increasing attention. Herein, two new series of thiazole and imidazo[1,2-a]pyridine derivatives containing a hydrazone substructure were designed and synthesized via a concise synthesis route. Bioassay results showed that most of the thiazole derivatives exhibited broad-spectrum fungistatic activities, which were exemplified by compounds 1c, 1e, 1g, 1h and 1j. In particular, compound 1e displayed excellent in vitro inhibitory effects with the EC50 values of 5.00, 18.24, 6.94, and 3.03 μg/mL against the fungi Botrytis cinerea, Cytospora sp, Fusarium graminearum, and Fusarium solani, respectively. Detached fruit experiments against tomato gray mold (caused by B. cinerea) in vivo revealed that the control efficiency of compound 1e at 10, 20 and 40 μg/mL for 5 days was 35.05%, 54.14% and 81.83%, respectively, which was comparable and even superior to that of the fungicide carbendazim. Additionally, the title compounds also showed remarkable larvicidal activity against M. separata and some compounds exhibited good aphicidal activity. In a word, the bioassay indicated that a certain number of title compounds had multiple biological activities. Given their excellent antifungal and larvicidal characteristics, these interesting derivatives based on the title compounds could be served as new scaffolds for the development of pesticide with multifunctional applications.

Systematic Studies on Anti-Cancer Evaluation of Stilbene and Dibenzo[b,f]oxepine Derivatives.

Cancer is one of the most common causes of human death worldwide; thus, numerous therapies, including chemotherapy, have been and are being continuously developed. In cancer cells, an aberrant mitotic spindle-a microtubule-based structure necessary for the equal splitting of genetic material between daughter cells-leads to genetic instability, one of the hallmarks of cancer. Thus, the building block of microtubules, tubulin, which is a heterodimer formed from α- and β-tubulin proteins, is a useful target in anti-cancer research. The surface of tubulin forms several pockets, i.e., sites that can bind factors that affect microtubules' stability. Colchicine pockets accommodate agents that induce microtubule depolymerization and, in contrast to factors that bind to other tubulin pockets, overcome multi-drug resistance. Therefore, colchicine-pocket-binding agents are of interest as anti-cancer drugs. Among the various colchicine-site-binding compounds, stilbenoids and their derivatives have been extensively studied. Herein, we report systematic studies on the antiproliferative activity of selected stilbenes and oxepine derivatives against two cancer cell lines-HCT116 and MCF-7-and two normal cell lines-HEK293 and HDF-A. The results of molecular modeling, antiproliferative activity, and immunofluorescence analyses revealed that compounds 1a, 1c, 1d, 1i, 2i, 2j, and 3h were the most cytotoxic and acted by interacting with tubulin heterodimers, leading to the disruption of the microtubular cytoskeleton.

Synthesis and Antifungal Activity of Derivatives of the Natural Product Griseofulvin against Phytopathogenic Fungi.

Natural products are important sources for the discovery of new pesticides. Chemical synthesis and structural modification can lead to pesticides. Despite abundant research in fungicide discovery for crop protection, there is an emerging need for the development of novel antifungal agrochemicals. Herein, 39 diversified griseofulvin derivatives were effectively synthesized from the natural product griseofulvin by diversity-oriented synthesis through the reactions of demethylation, ammonolysis, methylation, nitration, acylation, reduction, and chlorination. Among them, 31 derivatives were novel. All structures were characterized by 1H NMR, 13C NMR, and high-resolution mass spectrometry (HR-MS), and the antifungal activity was investigated against five phytopathogenic fungi. Compounds 5h and 5l had excellent activity against Botrytis cinerea (5h, IC50 = 17.29 ± 0.64 μg/mL) and Alternaria solani (5l, IC50 = 22.52 ± 0.79 μg/mL), respectively. Compound 9 exhibited the more promising activities against three target fungi, especially against Colletotrichum gloeosporioides (IC50 = 7.24 ± 0.66 μg/mL), which is obviously better than positive control hymexazol, thifluzamide, and parent compound griseofulvin. In addition, compound 10 showed significant and extensive activities against four target fungi Cytospora sp. (IC50 = 18.72 ± 0.35 μg/mL), C. gloeosporioides (IC50 = 31.39 ± 1.48 μg/mL), A. solani (IC50 = 40.82 ± 1.04 μg/mL), and Fusarium solani (IC50 = 36.81 ± 0.82 μg/mL). Unexpectedly, 11 and 12, the chlorinated products of compound 9, exhibited the most promising activity against C. gloeosporioides (IC50 = 4.48 ± 0.54 μg/mL for 11, 2.24 ± 0.76 μg/mL for 12). Furthermore, 12 showed remarkable activity against Cytospora sp. (IC50 = 5.85 ± 0.72 μg/mL). Additionally, in vivo antifungal activity against C. gloeosporioides, homology modeling, and docking analysis of 11, 12, and griseofulvin were conducted. All results indicated that 11 and 12 had potency as antifungal agents against C. gloeosporioides, and the modifications of the 2' and 4' positions of griseofulvin should be further explored for higher-activity lead compounds or potential agricultural fungicides.

Novel carboxamide and carbohydrazide functionalized pyridopyrimidine derivatives and their anticancer activity

A series of novel carboxamide and carbohydrazide functionalized pyridopyrimidine derivatives was prepared starting from 6-methyl/ethyl-2-oxo-4-(trifluoromethyl)-1,2-dihydropyridine-3-carbonitrile 1. Compound 1 on reaction with sulphuric acid gave compound 2. Compound 2 on reaction with chloroacetamide followed by reaction with EMME coupling and further cyclization gave compound 5. Compound 5 on reaction with hydrazine hydrate produced hydrazide derivatives 6. Compound 6 on reaction with diverse substituted aromatic aldehyde gave Schiff’s base derivatives 7a-j. Ester derivatives 5 on reaction with different aliphatic amine gave carboxamide derivatives 8a-f. All the final 7a-j and 8a-f compounds were evaluated for anti cancer activity against four human cancer cell lines such as HeLa - Cervical cancer (CCL-2), COLO 205- Colon cancer (CCL-222); HepG2- Liver cancer (HB-8065), MCF7 - Breast cancer (HTB-22) and promising compounds 7e, 7h and 7j have been identified.

Novel 1,4 benzothiazine 3-one derivatives as anticonvulsant agents: Design, synthesis, biological evaluation and computational studies

In this study, two series of novel 1,4-benzothiazine-3-one derivatives with alkyl substitution (series 1: 4a-4f) and aryl substitution (series 2: 4g-4l) were designed and synthesized based on the chemical scaffolds of perampanel, hydantoins, progabide and etifoxine as anti-convulsant agents. The chemical structures of the synthesized compounds were confirmed by FT-IR, 1H NMR and 13C NMR spectroscopy. Anti-convulsant effect of the compounds was examined through intraperitoneal pentylenetetrazol (i.p. PTZ) induced epilepsy mouse models. Compound 4h (4-(4-bromo-benzyl)− 4 H-benzo[b] [1,4] thiazin-3(4 H)-one) demonstrated a promising activity toward chemically-induced seizure experiment. Molecular dynamics simulation on GABA-Aergic receptors as a plausible mechanism were also done to achieve the binding and orientation of compounds in the active site of the target to evaluate the results of docking and experimental studies. The computational results were confirmed the biological activity. DFT study of 4c and 4h was performed on B3LYP/6–311 G** level of theory. Reactivity descriptors such as HOMO, LUMO, electron affinity, ionization potential, chemical potential, hardness and softness were studied in detail and show that 4h has higher activity than 4c. Also, the frequency calculations were performed on the same level of theory and the results are in line with experimental data. Moreover, in silico ADMET properties were done to establish a relationship between the physiochemical data of the designed compounds and their in-vivo activity. Appropriate plasma protein binding and high blood-brain barrier penetration are the main features of desired in-vivo performance.

Synthesis of Novel 2-(Cyclopentylamino)thiazol-4(5H)-one Derivatives with Potential Anticancer, Antioxidant, and 11β-HSD Inhibitory Activities.

In this study, a series of nine new 2-(cyclopentylamino)thiazol-4(5H)-one derivatives were synthesized, and their anticancer, antioxidant, and 11β-hydroxysteroid dehydrogenase (11β-HSD) inhibitory activities were tested. Anticancer activity has been assessed using the MTS (MTS: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay against human colon carcinoma (Caco-2), human pancreatic carcinoma (PANC-1), glioma (U-118 MG), human breast carcinoma (MDA-MB-231), and skin melanoma (SK-MEL-30) cancer cell lines. Cell viability reductions, especially in the case of Caco-2, MDA-MB-231, and SK-MEL-30 lines, were observed for most compounds. In addition, the redox status was investigated and oxidative, but nitrosative stress was not noted at a concentration of 500 µM compounds tested. At the same time, a low level of reduced glutathione was observed in all cell lines when treated with compound 3g (5-(4-bromophenyl)-2-(cyclopentylamino)thiazol-4(5H)-one) that most inhibited tumor cell proliferation. However, the most interesting results were obtained in the study of inhibitory activity towards two 11β-HSD isoforms. Many compounds at a concentration of 10 µM showed significant inhibitory activity against 11β-HSD1 (11β-hydroxysteroid dehydrogenase type 1). The compound 3h (2-(cyclopentylamino)-1-thia-3-azaspiro[4.5]dec-2-en-4-one) showed the strongest 11β-HSD1 inhibitory effect (IC50 = 0.07 µM) and was more selective than carbenoxolone. Therefore, it was selected as a candidate for further research.

Synthesis, Biological Evaluation and Docking Studies of 4H‐[1,2,3] thiadiazolo[4,5‐b]indole Hybrids as Antifungal Agents

AbstractHerein, we report the synthesis of 4H‐[1,2,3]thiadiazolo[4,5‐b]indole derivatives along with their pharmacological activity against different Gram‐(+ve), Gram‐(−ve) and fungal strains. Structures of all the compounds were elucidated by NMR, HRMS, LC–MS and IR analysis methods. The biological studies revealed that 4H‐[1,2,3]thiadiazolo[4,5‐b]indole and 5‐nitro‐4H‐[1,2,3]thiadiazolo[4,5‐b]indole compounds possess good antifungal activity with IC50 values of 10.8±2.2, 16.0±0.9 and MIC values of 25 and 36, respectively. At the same time, compound 4H‐[1,2,3]thiadiazolo[4,5‐b]indole possesses weak antibacterial activity with an IC50 value of 34.1±1.0 and MIC >100. Molecular docking performed on the compound 4H‐[1,2,3]thiadiazolo[4,5‐b]indole showed a high affinity with binding energy −6.0 and 5.7 kcal mol‐1 and formed key interactions with the active site of transferase enzyme (6AEF) and integrin protein (3FCU).

Antiseizure Properties of Histamine H3 Receptor Antagonists Belonging 3,4-Dihydroquinolin-2(1H)-Ones.

H3R is becoming an attractive and promising target for epilepsy treatment as well as the discovery of antiepileptics. In this work, a series of 6-aminoalkoxy-3,4-dihydroquinolin-2(1H)-ones was prepared to screen their H3R antagonistic activities and antiseizure effects. The majority of the target compounds displayed a potent H3R antagonistic activity. Among them, compounds 2a, 2c, 2h, and 4a showed submicromolar H3R antagonistic activity with an IC50 of 0.52, 0.47, 0.12, and 0.37 μM, respectively. The maximal electroshock seizure (MES) model screened out three compounds (2h, 4a, and 4b) with antiseizure activity. Meanwhile, the pentylenetetrazole (PTZ)-induced seizure test gave a result that no compound can resist the seizures induced by PTZ. Additionally, the anti-MES action of compound 4a fully vanished when it was administrated combined with an H3R agonist (RAMH). These results showed that the antiseizure role of compound 4a might be achieved by antagonizing the H3R receptor. The molecular docking of 2h, 4a, and PIT with the H3R protein predicted their possible binding patterns and gave a presentation that 2h, 4a, and PIT had a similar binding model with H3R.

Design, synthesis, biochemical and in silico characterization of novel naphthalene-thiourea conjugates as potential and selective inhibitors of alkaline phosphatase.

Naphthalene ring is present in a number of FDA-approved, commercially available medications, including naphyrone, terbinafine, propranolol, naproxen, duloxetine, lasofoxetine, and bedaquiline. By reacting newly obtained 1-naphthoyl isothiocyanate with properly modified anilines, a library of ten novel naphthalene-thiourea conjugates (5a-5j) were produced with good to exceptional yields and high purity. The newly synthesized compounds were observed for their potential to inhibit alkaline phosphatase (ALP) and scavenge free radicals. All of the investigated compounds displayed a more powerful inhibitory profile than the reference agent, KH2PO4 particularly compound 5h and 5a exhibited strong inhibitory potential against ALP with IC50 value of 0.365 ± 0.011 and 0.436 ± 0.057 µM respectively. In addition, Lineweaver-Burk plots revealed the non-competitive inhibition mode of the most powerful derivative i.e., 5h (ki value 0.5 µM). To investigate the putative binding mode of selective inhibitor interactions, molecular docking was performed. It is recommended that future research will focus on developing selective alkaline phosphatase inhibitors by modifying the structure of the 5h derivative.

Discovery of highly potent proapoptotic antiestrogens in a series of androst-5,16-dienes D-modified with imidazole-annulated pendants

Heterocyclic derivatives of steroid hormones are potent anticancer agents, which are used in the chemotherapy of breast and prostate cancers. Here, we describe a novel series of androstenes, D-modified with imidazole-annulated pendants, with significant anticancer activity. Novel C17-linked imidazole-annulated heterocyclic derivatives of dehydropregnenolone acetate were synthesized by the cyclocondensation with amidines using 3β-acetoxy-21-bromopregna-5,16-dien-20-one as the substrate. The antiproliferative potency of all the synthesized compounds was evaluated against human prostate (22Rv1) and human breast (MCF7) cancer cell lines and cytochromes P450. The lead compound, imidazo[1,2-a]pyridine derivative 3h, was revealed to be a promising candidate for future anticancer drug design, particularly against ERα-positive breast cancer. Lead compound 3h was found to be selective against MCF7 cells with IC50 of 0.1 μM and to act as both a potent selective agent blocking estrogen receptor α, which is involved in the stimulation of breast cancer growth, and an effective apoptosis inducer. The potential ability of compound 3h to bind to ERα was studded using molecular docking and molecular dynamics simulation. The selectivity analysis showed that lead steroid 3h produces no effects on cytochromes P450 CYP17A1, CYP7A1, and CYP21A2.

Design, synthesis, α‐glucosidase inhibition, pharmacokinetic, and cytotoxic studies of new indole‐carbohydrazide‐phenoxy‐N‐phenylacetamide derivatives

A new series of indole-carbohydrazide-phenoxy-N-phenylacetamide derivatives 7a-l were designed, synthesized, and screened for their α-glucosidase inhibitory abilities and cytotoxic effects. The results obtained in the α-glucosidase inhibition assay indicated that most of the synthesized derivatives displayed good to moderate inhibitory abilities (Ki values ranging from 14.65 ± 2.54 to 37.466 ± 6.46 μM) when compared with the standard drug acarbose (Ki = 42.38 ± 5.73 μM). Among them, 2-mehoxy-phenoxy derivatives 7l and 7h with 4-nitro and 4-chloro substituents on the phenyl ring of the N-phenylacetamide moiety, respectively, displayed the most inhibition effects. The inhibitory mechanism of these compounds was investigated by molecular docking studies. The in vitro cytotoxicity assay showed that only one compound, 2-methoxy-phenoxy derivative 7k with a 4-bromo substituent on the phenyl ring of the N-phenylacetamide moiety, exhibited moderate cytotoxicity against the human non-small-cell lung cancer cell line A549 and the rest of the compounds show almost no cytotoxicity. Further cytotoxic evaluations were also performed on compound 7k. The in silico pharmacokinetic study predicted that the selected compounds 7l and 7h are likely to be orally active.

Abstract 479: Novel specific PKM2 inhibitor, compound 3h, induces apoptotic and autophagic cell death through Akt/mTOR signaling pathway in prostate cancer cells

Abstract Pyruvate kinase M2 (PKM2) is a key enzyme involved in the regulation of glycolysis. Although PKM2 is overexpressed in various tumor tissues, its functional role in cancer chemotherapy remains unclear. In this study, we investigated the anticancer activity of novel PKM2 inhibitors in the regulation of cell metabolism and its associated pathways in prostate cancer cells. To evaluate the molecular basis of specific PKM2 inhibitors, the interactions of compounds 3h and 3K with the PKM2 protein were assessed via molecular docking. We found that, compared to compound 3K, compound 3h exhibited a higher binding affinity for PKM2. Moreover, compound 3h significantly inhibited the pyruvate kinase activity and PKM2 expression. Cytotoxicity and colony formation assays revealed the potent anticancer activity of compound 3h against LNCaP cells. Compound 3h significantly increased the apoptotic and autophagic cell death in LNCaP cells. In addition, compound 3h induced AMPK activation along with the inhibition of mTOR/p70S6K pathway. Furthermore, compound 3h significantly inhibited glycolysis and mitochondrial respiration, as determined by analyzing extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) production. Our results revealed that compound 3h caused apoptotic and autophagic cell death by inhibiting cancer cell metabolism in LNCaP cells. Therefore, blocking glycolytic pathways using specific PKM2 inhibitors can be used to target cancer cell metabolism in PKM2-overexpressed prostate cancer cells. Citation Format: Chunxue Jiang, Tian Zheng, HwaYoung Cha, Hyung Sik Kim. Novel specific PKM2 inhibitor, compound 3h, induces apoptotic and autophagic cell death through Akt/mTOR signaling pathway in prostate cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 479.

Synthesis of amide derivatives of benzimidazole-isoxazoles as anticancer agents

A new amide-containing benzimidazole-isoxazole (9a-j) derivative was synthesized and evaluated for anticancer activities against a panel of human cancer cell lines including PC3 (prostate cancer), DU-145 (prostate cancer), A549 (lung cancer), and MCF-7 (breast cancer) using the MTT assay.The reference drug's IC50 values ranged from 0.022±0.0051 to 18.6 ± 6.22 µM, whereas the compounds' values ranged from 1.97 ± 0.45 to 3.08 ± 0.135 µM. The compounds 9a, 9b, 9c, 9d, 9e, and 9h showed the strongest anticancer activity of all of them.