Heterocyclic Anticancer Compounds: Recent Advances and the Paradigm Shift towards the Use of Nanomedicine's Tool Box

Copper(II) quinoxolinol imidazolium complexes in catalytic oxidation of benzylic and heterocyclic alcohols

A novel copper(II) quinoxolinol complex has been prepared using a condensation reaction based on previous studies. The copper(II) quinoxolinol salen complex has been applied as a catalyst using tert-butyl hydroperoxide (TBHP) as the oxidant, demonstrating that benzylic and heterocyclic alcohols can be converted efficiently to the corresponding aldehydes. Excellent yields can be achieved (up to 99%) within a short reaction time and with great tolerance for functional groups.

Investigating the effect of ligand structure on the anticancer properties of several new Co(II) complexes of vitaminB3-based phosphoramides

Nicotinamide, known as Vitamin-B3, has shown promising potential in improving various medical conditions. Carbacylamidophosphates (CAPh) are versatile phosphoramide ligands with a wide range of applications in both biochemistry and chemistry. Herein, to obtain compounds with enhanced anticancer activity and study the effect of the structure on this activity, four new Co(II) complexes of vitaminB3-based CAPh ligands with the formula of CoCl2[3-NC5H4CONHPO(NC5H10)2]2(C1), CoCl2[3-NC5H4CONHPO(NC5H9CH3)2]2(C2), CoCl2[3-NC5H4CONHPO(NC6H12)2]2(C3), and CoCl2[3-NC5H4CONHPO(NC4H10)2]2(C4) were designed and synthesized. FT-IR, UV-Vis, Atomic Absorption (AAS),1H, 13C, and 31PNMR, and Mass spectroscopies beside CHN and Molar conductivity methods were utilized to characterize the synthesized compounds. Using MTT-assay and Flow Cytometry, the anticancer effects of these complexes were studied on three distinct cell lines, including one normal cell line (MCF10A) and two cancer cell lines (MDA-MB-231, MCF-7). Results showed that our ligands could form complexes by coordinating with cobalt, which, not only have a very strong killing effect on cancer cells but also have a higher level of safety for normal cells and are more cost-efficient than Cisplatin. C3 was the most effective complex at inhibiting the growth of MCF-7 and MDA-MB-231 cells which exhibited a remarkable 97.5 % reduction in cancer cell growth and a Selectivity Index up to > 37. This is an impressive 93 and 54 times more selective and safer than commonly used drugs like Cisplatin and Doxorubicin, respectively.Flow Cytometry analysis shows complex-induced breast cancer cell apoptosis.The ligands' amine structure and ring size can directly impact the complexes' anticancer effect and safety for normal cells.

Design, synthesis, molecular modeling and evaluation of 2,4-diaminopyrimidine analogues as promising colorectal cancer drugs

The potential of cyclin-dependent kinases (CDKs) as therapeutic targets in cancer treatment is well established. In this study, we present our investigation into a group of 2,4-diaminopyrimidine derivatives that potently inhibit CDK9 and are cytotoxic when tested in colorectal cancer cell lines. We designed and synthesized forty analogues by altering substitutions at C-2 and C-4 position of the pyrimidine system. Among them, compounds 16 h and 16j exhibited strong inhibitory potency against both CDK9 enzymes (IC50 = 11.4 ± 1.4 nM, IC50 = 10.2 ± 1.3 nM respectively) with a significant preference for one over the other, and cytotoxic potency (IC50 = 61 ± 2 nM, IC50 = 20 ± 1 nM respectively) against HCT-116 was discovered through substantial modifications to its structure. Further investigations revealed that compounds 16 h and 16j were directly bound to CDK9, resulting in the suppression of its downstream signaling pathway. This inhibition of cell proliferation occurred by impeding the progression of the cell cycle and inducing apoptosis in cells by suppressing the phosphoryl RNA pol II Ser2. Significantly, compound 16 h and 16j effectively suppressed tumor growth in a xenograft mouse model and exhibited no apparent toxicity. This indicates that CDK9 inhibitors hold great potential as a therapeutic approach for colorectal cancer treatment. Therefore, the aforementioned discoveries are vital for the development of CDK9 inhibitors for the treatment of cancer.

Discovery of novel dihydro-pyrimidine hybrids: insight into the design, synthesis, biological evaluation and absorption, distribution, metabolism and excretion studies

Aim: By keeping in aspects, the pharmacological potential of heterocyclic compounds, pyrimidine-based compounds were designed, synthesized and evaluated for α-amylase inhibitory potential.Materials & methods: Five new series 1a-l, 2a-d, 3a-d, 4a-d and 5a-d of 1,2,3,4-tetrahydroprimidine-5-carboxylate derivatives were designed by de novo method by taking Alogliptin as reference compound. Here in we describe synthesis and characterization of compounds as potential α-amylase inhibitor.Results: Structure activity relationship (SAR), in vitro analysis and molecular modelling approaches generate compounds 1 h, 1i, 1k and 4c as potential lead with good α-amylase inhibitory selection. However, compound 1k failed the criteria of optimization as drug lead by ADME studies while all other compounds showed optimum range for all in silico ADME parameters.Conclusion: Therefore, these compounds can serve as potential lead candidate in developing anti-diabetic therapy.

Design, synthesis, molecular docking, and evaluation of sulfonyl quinazoline analogues as promising liver cancer drugs

Inhibiting cyclin-dependent kinases (CDK) offers an important arsenal for cancer treatments by interfering with apoptotic proteins related to cancer. Novel selective cyclin-dependent kinases inhibitors using the Quinazoline as the cap with multiple electronic donating (EDG) and/or electron withdrawing group (EWG) substituted Aniline chain at the C-2 position were designed, synthesized, and evaluated for activity against liver cancer. Among the tested compounds, compounds B34 and B35 emerged as potent candidates in the series, with IC50 values of 0.102 ± 0.04 µM and 0.058 ± 0.003 µM, respectively. They also suppressed the enzymatic activity of CDK2/cyclinA2 selectively. Further biological studies revealed that compounds B34 and B35 arrested the cell cycle, and induced apoptosis in HepG-2 cancer cells through a Caspase-mediated mechanism, facilitating the release of Cyt-c through modulation of Caspase-3 expression. More importantly, compounds B34 and B35 suppressed the xenografted tumor growth in mice in a dose-dependent manner. Finally, through a molecular docking study, it was confirmed that compoundsB34 andB35 retained crucial hydrogen bonding and hydrophobic interactions with CDK receptor, rationalizing their higher efficacy compared to other compounds in the series. Taken together, the Quinazoline derivatives B34 and B35 may serve as novel chemotherapeutic agents through inhibition of CDK.

A New Class of Benzo[b]thiophene-chalcones as Cholinesterase Inhibitors: Synthesis, Biological Evaluation, Molecular Docking and ADME Studies

In this study, heterocyclic compounds containing a benzothiophene scaffold were designed and synthetized, and their inhibitory activity against cholinesterases (ChE) and the viability of SH-SY5Y cells have been evaluated. Benzothiophenes 4a-4i and benzothiophene-chalcone hybrids 5a-5i were tested against both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), revealing interesting structure-activity relationships. In general, benzothiophene-chalcone hybrids from series 5 proved to be better inhibitors of both enzymes, with compound 5f being the best AChE inhibitor (IC50 = 62.10 μM) and compound 5h being the best BChE inhibitor (IC50 = 24.35 μM), the last one having an IC50 similar to that of galantamine (IC50 = 28.08 μM), the reference compound. The in silico ADME profile of the compounds was also studied. Molecular docking calculations were carried out to analyze the best binding scores and to elucidate enzyme-inhibitors' interactions.

Analysis of antiproliferative activity of new half-sandwich arene Ru(II) thiophene based aroylhydrazone complexes

Efforts in researching the efficient anti-tumor properties of three novel arene ruthenium(II) complexes incorporating thiophene-based aroylhydrazone ligands have been undertaken. The complexes' elemental composition was [(η6-p-cymene)Ru(L)Cl]. They were comprehensively characterized through elemental and spectroscopic analyses (FT-IR, UV-vis, NMR, and HR-MS). Single crystal X-ray diffraction studies revealed a pseudo-octahedral geometry with bidentate coordination of the ligands in a representative complex. The in vitro assessment of the complexes' cancer cell growth inhibition was conducted using the MTT assay against A549 (human lung carcinoma), HeLa (human cervical carcinoma), HuH-7 (hepatocellular carcinoma), and NIH-3T3 (mouse fibroblast non-cancerous cell line). Results indicated significant cytotoxicity across all cancer cell lines, with IC50 concentrations of complex 2 being 6.8 μM for A549, 11.6 μM for HeLa, and 9.4 μM for HuH-7, compared to cisplatin with IC50 values of 18.9 μM, 17.68 μM, and 24 μM respectively. Notably, complex 2 demonstrated particularly promising cytotoxicity against all tested cancerous cell lines. Fluorescent staining analysis such as acridine orange/ethidium bromide (AO-EB) and HOECHST 33342 revealed cell death mechanisms involving membrane disintegration and nuclear condensation following treatment with complex 2. Further studies were conducted to measure reactive oxygen species (ROS) levels using the dichlorodihydrofluorescein diacetate (DCFH-DA) assay, and mitochondrial membrane potential (MMP) was assessed using the JC-1 dye assay. These studies demonstrated that complex 2 increased ROS levels, decreased membrane potential, and promoted mitochondrial dysfunction-mediated cell death pathways. Additionally, flow cytometry analysis, utilizing dual staining of Annexin V-FITC and propidium iodide (PI), was employed to quantitatively study apoptosis induction.

Multitarget Pharmacology of Sulfur-Nitrogen Heterocycles: Anticancer and Antioxidant Perspectives

Cancer and oxidative stress are interrelated, with reactive oxygen species (ROS) playing crucial roles in physiological processes and oncogenesis. Excessive ROS levels can induce DNA damage, leading to cancer, and disrupt antioxidant defenses, contributing to diseases like diabetes and cardiovascular disorders. Antioxidant mechanisms include enzymes and small molecules that mitigate ROS damage. However, cancer cells often exploit oxidative conditions to evade apoptosis and promote tumor growth. Antioxidant therapy has shown mixed results, with timing and cancer-type influencing outcomes. Multifunctional drugs targeting multiple pathways offer a promising approach, reducing side effects and improving efficacy. Recent research focuses on sulfur-nitrogen heterocyclic derivatives for their dual antioxidant and anticancer properties, potentially enhancing therapeutic efficacy in oncology. The newly synthesized compounds often do not demonstrate both antioxidant and anticancer properties simultaneously. Heterocyclic rings are typically combined with phenyl groups, where hydroxy substitutions enhance antioxidant activity. On the other hand, electron-withdrawing substituents, particularly at the p-position on the phenyl ring, tend to enhance anticancer activity.

Dimensional Reduction of Metal-Organic Frameworks for Photocatalytic Synthesis of Fused Tetracyclic Heterocycles

Heterogeneous palladium catalysts with high efficiency, high Pd atom utilization, simplified separation, and recycle have attracted considerable attention in the field of synthetic chemistry. Herein, we reported a zirconium-based two-dimensional metal-organic framework (2D-MOF)-based Pd(II) photocatalyst (Zr-Ir-Pd) by merging the Ir photosensitizers and Pd(II) species into the skeletons of the 2D-MOF for the Pd(II)-catalyzed oxidation reaction. Morphological and structural characterization identified that Zr-Ir-Pd with a specific nanoflower-like structure consists of ultrathin 2D-MOF nanosheets (3.85 nm). Due to its excellent visible-light response and absorption capability, faster transfer and separation of photogenerated carriers, more accessible Pd active sites, and low mass transfer resistance, Zr-Ir-Pd exhibited boosted photocatalytic activity in catalyzing sterically hindered isocyanide insertion of diarylalkynes for the construction of fused tetracyclic heterocycles, with up to 12 times the Pd catalyst turnover number than the existing catalytic systems. In addition, Zr-Ir-Pd inhibited the competitive agglomeration of Pd(0) species and could be reused at least five times, owing to the stabilization of 2D-MOF on the single-site Pd and Ir sites. Finally, a possible mechanism of the photocatalytic synthesis of fused tetracyclic heterocycles catalyzed by Zr-Ir-Pd was proposed.

Design, synthesis, in-silico studies and apoptotic activity of novel amide enriched 2-(1H)- quinazolinone derivatives

Cancer is a broad classification of diseases that can affect any organ or body tissue due to aberrant cellular proliferation for unknown reasons. Many present chemotherapeutic drugs are highly toxic and have little selectivity. Additionally, they lead to the development of medication resistance. Therefore, developing tailored chemotherapeutic drugs with minimal side effects and good selectivity is crucial for cancer treatment. 2-(1H)-Quinazolinone is one of the vital scaffold and anticancer activity is one of the prominent biological activities of this class. Here we report the novel set of amide-enriched 2-(1H)-quinazolinone derivatives (7a-j) and their apoptotic activity with the help of MTT assay method against four human cancer cell lines: PC3 (prostate cancer), DU-145 (prostate cancer), A549 (lung cancer), and MCF7 (breast cancer). When compared to etoposide, every synthetic test compound (7a-j) exhibited moderate to excellent activity. The IC50 values of the new amide derivatives (7a-j) varied from 0.07 ± 0.0061 μM to 10.8 ± 0.69 μM. While the positive control, etoposide, exhibited 1.97 ± 0.45 μM to 3.08 ± 0.135 μM range. Among the novel amide derivatives (7a-j), in particular, 7i and 7j showed strong apoptotic activity against MCF7; 7h showed against PC3, and 7g showed against DU-145. Molecular docking studies of test compounds (7a-j) with the EGFR tyrosine kinase domain (PDB ID: 1M17) protein provided the significant docking scores for each test compound (7a-j) (-9.00 to -9.67 kcal/mol). Additionally, DFT investigations and MD simulations validated the predictions of molecular docking. According to the findings of the ADME analysis, oral absorption by humans is anticipated to be higher than 85 % for all test compounds.

A review on potential heterocycles for the treatment of glioblastoma targeting receptor tyrosine kinases

Glioblastoma, the most aggressive form of brain tumor, poses significant challenges in terms of treatment success and patient survival. Current treatment modalities for glioblastoma include radiation therapy, surgical intervention, and chemotherapy. Unfortunately, the median survival rate remains dishearteningly low at 12-15 months. One of the major obstacles in treating glioblastoma is the recurrence of tumors, making chemotherapy the primary approach for secondary glioma patients. However, the efficacy of drugs is hampered by the presence of the blood-brain barrier and multidrug resistance mechanisms. Consequently, considerable research efforts have been directed toward understanding the underlying signaling pathways involved in glioma and developing targeted drugs. To tackle glioma, numerous studies have examined kinase-downstream signaling pathways such as RAS-RAF-MEK-ERK-MPAK. By targeting specific signaling pathways, heterocyclic compounds have demonstrated efficacy in glioma therapeutics. Additionally, key kinases including phosphatidylinositol 3-kinase (PI3K), serine/threonine kinase, cytoplasmic tyrosine kinase (CTK), receptor tyrosine kinase (RTK) and lipid kinase (LK) have been considered for investigation. These pathways play crucial roles in drug effectiveness in glioma treatment. Heterocyclic compounds, encompassing pyrimidine, thiazole, quinazoline, imidazole, indole, acridone, triazine, and other derivatives, have shown promising results in targeting these pathways. As part of this review, we propose exploring novel structures with low toxicity and high potency for glioma treatment. The development of these compounds should strive to overcome multidrug resistance mechanisms and efficiently penetrate the blood-brain barrier. By optimizing the chemical properties and designing compounds with enhanced drug-like characteristics, we can maximize their therapeutic value and minimize adverse effects. Considering the complex nature of glioblastoma, these novel structures should be rigorously tested and evaluated for their efficacy and safety profiles.

Synthesis, in vitro and in silico anticancer evaluation of novel pyridin-2-yl estra-1,3,5(10)-triene derivatives

Aim: The aim of this study was the synthesis of steroid compounds with heterocyclic rings and good anticancer properties. Materials & methods: The synthesis, in silico and in vitro anticancer testing of novel pyridin-2-yl estra-1,3,5(10)-triene derivatives was performed. Results: All synthesized compounds have shown promising results for, antiproliferative activity, relative binding affinities for the ligand binding domains of estrogen receptors α, β and androgen receptor, aromatase binding potential, and inhibition of AKR1C3 enzyme. Conclusion: 3-Benzyloxy (17E)-pycolinilidene derivative 9 showed the best antitumor potential against MDA-MB-231 cell line, an activity that can be explained by its moderate inhibition of AKR1C3. Molecular docking simulation indicates that it binds to AKR1C3 in a very similar orientation and geometry as steroidal inhibitor EM1404.

Anti-migratory and cytotoxic effect of indole derivative in C6 glioma cells

Gliomas are among the most common primary malignant brain tumors. Despite advances in cancer treatment, survival is very low, so the discovery of new therapeutic agents is essential. In this context, indole is an important source for the development of new bioactive molecules. A pharmacological screening of ten indole derivatives was carried out to evaluate the cytotoxic capacity against three tumor cell lines. After pharmacological screening, three compounds were selected, based on their high capacity to reduce cell proliferation, and their IC50 values were determined. Compound 9 exhibited the highest cytotoxic activity (IC50 = 0.4 μg/mL) in gliomas (C6 cell line), and were selected for further experiments. C6 cells were treated with compound 9 to evaluate cellular mechanisms such as colony formation and cell migration capacity and morphological alterations. Compound 9 decreased clone formation (0.4 and 0.8 μg/mL), and inhibited migration (0.2-0.8 μg/mL) in C6 cells. Morphological changes in cells treated with the compound 9 were also observed, such as chromatin condensation, and disorganization in cellular stress beams. Indole derivatives had a cytotoxic effect on tumor cells, and compound 9 showed the best anti-proliferative and anti-migratory activity in glioma cells.

A Comparison of In Vitro Studies between Cobalt(III) and Copper(II) Complexes with Thiosemicarbazone Ligands to Treat Triple Negative Breast Cancer

Metal complexes have gained significant attention as potential anti-cancer agents. The anti-cancer activity of [Co(phen)2(MeATSC)](NO3)3•1.5H2O•C2H5OH 1 (where phen = 1,10-phenanthroline and MeATSC = 9-anthraldehyde-N(4)-methylthiosemicarbazone) and [Cu(acetylethTSC)Cl]Cl•0.25C2H5OH 2 (where acetylethTSC = (E)-N-ethyl-2-[1-(thiazol-2-yl)ethylidene]hydrazinecarbothioamide) was investigated by analyzing DNA cleavage activity. The cytotoxic effect was analyzed using CCK-8 viability assay. The activities of caspase 3/7, 9, and 1, reactive oxygen species (ROS) production, cell cycle arrest, and mitochondrial function were further analyzed to study the cell death mechanisms. Complex 2 induced a significant increase in nicked DNA. The IC50 values of complex 1 were 17.59 μM and 61.26 μM in cancer and non-cancer cells, respectively. The IC50 values of complex 2 were 5.63 and 12.19 μM for cancer and non-cancer cells, respectively. Complex 1 induced an increase in ROS levels, mitochondrial dysfunction, and activated caspases 3/7, 9, and 1, which indicated the induction of intrinsic apoptotic pathway and pyroptosis. Complex 2 induced cell cycle arrest in the S phase, ROS generation, and caspase 3/7 activation. Thus, complex 1 induced cell death in the breast cancer cell line via activation of oxidative stress which induced apoptosis and pyroptosis while complex 2 induced cell cycle arrest through the induction of DNA cleavage.

Visible-Light-Driven Deoxygenative Heteroarylation of Alcohols with Heteroaryl Sulfones

The visible-light-promoted deoxygenative radical heteroarylation of alcohols was achieved in the absence of any external photosensitizers. The processes occur through the generation of xanthate salts from alcohols, followed by SET and fragmentation, delivering alkyl radicals to react with heteroaryl sulfones. This method is amenable for a wide range of alcohols with good functional group tolerance, providing a practical strategy for the alkylation of benzo-heteroaromatics. Mechanism studies indicate that direct visible-light excitation of xanthate anions and subsequent SET initiate the reactions.

Green synthesis and investigation of antioxidant and antibacterial activity of new derivatives of chromenoazepines employing CuO/TiO2@MWCNTs

The synthesis of novel, high-yield derivatives of chromenoazepine was investigated in this work. CuO/TiO2@MWCNTs was used as a nanocatalyst in a multicomponent reaction involving 4-aminocumarine, activated acetylenic chemicals, and alkyl bromide in room temperature water to create these novel compounds. Using MCRs of 4-aminocumarine, isothiocyanate, and alkyl bromide in the presence of CuO/TiO2@MWCNTs as nanocatalysts in room-temperature water, chromenothiazepines were synthesized under comparable conditions. The freshly synthesized azepine exhibits antioxidant activity since its NH group has undergone two evaluation processes. Additionally, using two types of Gram-negative bacteria in a disk distribution procedure, the antibacterial activity of recently developed azepines was evaluated, and these compounds also inhibited the growth of Gram-positive bacteria. This method's benefits include quick reaction times, large product yields, and straightforward catalyst and product separation through easy steps.

Seleno-Warfare against Cancer: Decoding Antitumor Activity of Novel Acylselenoureas and Se-Acylisoselenoureas

Currently, cancer remains a global health problem. Despite the existence of several treatments, including chemotherapy, immunotherapy, and radiation therapy, the survival rate for most cancer patients, particularly those with metastasis, remains unsatisfactory. Thus, there is a continuous need to develop novel, effective therapies. In this work, 22 novel molecules containing selenium are reported, including seven Se-acylisoselenoureas synthesized from aliphatic carbodiimides as well as acylselenoureas with the same carbo- and heterocycles and aliphatic amines. After an initial screening at two doses (50 and 10 µM) in MDA-MB-231 (breast), HTB-54 (lung), DU-145 (prostate), and HCT-116 (colon) tumor cell lines, the ten most active compounds were identified. Additionally, these ten hits were also submitted to the DTP program of the NCI to study their cytotoxicity in a panel of 60 cancer cell lines. Compound 4 was identified as the most potent antiproliferative compound. The results obtained showed that compound 4 presented IC50 values lower than 10 µM in the cancer cell lines, although it was not the most selective one. Furthermore, compound 4 was found to inhibit cell growth and cause cell death by inducing apoptosis partially via ROS production. Overall, our results suggest that compound 4 could be a potential chemotherapeutic drug for different types of cancer.

The Effect of 4-(Dimethylamino)phenyl-5-oxopyrrolidines on Breast and Pancreatic Cancer Cell Colony Formation, Migration, and Growth of Tumor Spheroids

A series of hydrazones, azoles, and azines bearing a 4-dimethylaminophenyl-5-oxopyrrolidine scaffold was synthesized. Their cytotoxic effect against human pancreatic carcinoma Panc-1 and triple-negative breast cancer MDA-MB-231 cell lines was established by MTT assay. Pyrrolidinone derivatives 3c and 3d, with incorporated 5-chloro and 5-methylbenzimidazole fragments; hydrazone 5k bearing a 5-nitrothien-2-yl substitution; and hydrazone 5l with a naphth-1-yl fragment in the structure significantly decreased the viability of both cancer cell lines. Compounds 3c and 5k showed the highest selectivity, especially against the MDA-MB-231 cancer cell line. The EC50 values of the most active compound 5k against the MDA-MB231 cell line was 7.3 ± 0.4 μM, which were slightly higher against the Panc-1 cell line (10.2 ± 2.6 μM). Four selected pyrrolidone derivatives showed relatively high activity in a clonogenic assay. Compound 5k was the most active in both cell cultures, and it completely disturbed MDA-MB-231 cell colony growth at 1 and 2 μM and showed a strong effect on Panc-1 cell colony formation, especially at 2 μM. The compounds did not show an inhibitory effect on cell line migration by the 'wound-healing' assay. Compound 3d most efficiently inhibited the growth of Panc-1 spheroids and reduced cell viability in MDA-MB-231 spheroids. Considering these different activities in biological assays, the selected pyrrolidinone derivatives could be further tested to better understand the structure-activity relationship and their mechanism of action.

Green preparation of new pyrimidine triazole derivatives via one-pot multicomponent reactions of guanidine

In this research the goal was to produce novel pyrimidine triazole compounds in high yields using triethylamin as an efficient catalyst. These new compounds were synthesized by using multicomponent reaction of aldehydes, guanidine, electron deficient acetylenic compounds, tert-butyl isocyanide and hydrazonoyle chloride in aqueous media. Due to the presence of an NH group, which was assessed using two different methodologies, newly synthesized pyrimidine triazoles have antioxidant properties. Additionally, the antibacterial activity of newly created pyrimidine triazoles was assessed using the disk distribution method with two different types of Gram-positive bacteria and Gram-negative bacteria, demonstrating that the use of these compounds prevented the growth of bacteria. Applied to the preparation of pyrimidine triazole derivatives, this method has short reaction times, high product yields, and the ability to separate catalyst and product using simple procedures.

Rational design for novel heterocyclic based Donepezil analogs for Alzheimer's disease: an in silico approach

Alzheimer's disease (AD) is a progressive neurodegenerative disease and has devastating impacts on the elderly population. During the last two decades, there has been a significant focus on developing effective and safe treatments for AD. Acetylcholinesterase (AChE) has been identified as one of the primary therapeutic targets for developing drug candidates for AD. However, there is still a need for more efficient therapies. In this study, our aim is to design a new series of heterocyclic-based AChE inhibitors inspired by a standard drug. Here, we carried out molecular docking, drug-likeliness characteristics, and molecular dynamics (MD) to predict important pharmacophore features and understand the inhibitory mechanism of the designed inhibitors towards the AChE. We have designed 112 new derivatives by replacing the piperidine moiety of Donepezil with the different five and six-membered heterocyclic rings and selected 15 compounds that show higher or comparable docking scores as compared to standard Donepezil and pose no risk for carcinogenicity. Furthermore, MD results imply the structural stability of the selected docked complexes and seven exhibit a stronger binding affinity towards the AChE than Donepezil. Thus, heterocyclic-based derivatives based on oxazole, pyrazole, and tetrahydropyran may be potential therapeutic candidates for AD. Our structure-based drug design approach allows us to identify and gain insight into the structural stability of the inhibitor-protein complex and the inhibition mechanism of the newly designed inhibitors. The present finding might be an initial selection for developing a new inhibitor for AD and provide a direction for further experiments on its biological activities.Communicated by Ramaswamy H. Sarma.

FDA-approved heterocyclic molecules for cancer treatment: Synthesis, dosage, mechanism of action and their adverse effect

As the incorporation of heterocycles increases the physical characteristics and biological activity of pharmacological molecules, heterocyclic scaffolds are commonly discovered as common cores in a wide spectrum of biologically active drugs. In the contemporary context, many heterocycles have arisen, playing vital roles in diverse pharmaceutical compounds that benefit humanity. Over 85 % of FDA-approved medication molecules contain heterocycles, and most importantly, numerous heterocyclic medicinal molecules indicate potential benefits against a range: of malignancies. The unique flexibility and dynamic core scaffold of these compounds have aided anticancer research. These medications are used to treat cancer patients by targeting particular genes, enzymes, and receptors. Aside from the drugs that are now on the market, numerous forms are being researched for their potential anti-cancer activity. Here in this review, we classified some molecules and biologically active heterocycles containing anticancer medicinal moieties approved by the FDA between 2019 and 2021 based on their use in various forms of cancer. We will focus on those that are suitable for cancer treatment, as well as the essential biochemical mechanisms of action, biological targets, synthetic methods, and inherent limiting considerations in their use.

Synthesis, in vitro Α-Glucosidase, and acetylcholinesterase inhibitory activities of novel Indol-Fused Pyrano[2,3-D]Pyrimidine compounds

In this study, new indol-fused pyrano[2,3-d]pyrimidines were designed and synthesized. These products were obtained in moderate to good yields and their structures were assigned by NMR, MS, and IR analysis. Afterwards, the biological important of the products was highlighted by evaluating in vitro for α-glucosidase inhibitory activity as well as acetylcholinesterase (AChE) inhibitory activity. Eleven products revealed substantial inhibitory activity against α-glucosidase enzyme, among which, two most potent products 11d,e were approximately 93-fold more potent than acarbose as a standard antidiabetic drug. Besides that, product 11k exhibited good AChE inhibition. The substituents on the 5-phenyl ring, attached to the pyran ring, played a critical role in inhibitory activities. The biological potencies have provided an opportunity to further investigations of indol-fused pyrano[2,3-d]pyrimidines as potential anti-diabetic agents.

Thiazole, Isatin and Phthalimide Derivatives Tested in vivo against Cancer Models: A Literature Review of the Last Six Years

BACKGROUND

Cancer is a disease characterized by the abnormal multiplication of cells and is the second leading cause of death in the world. The search for new effective and safe anticancer compounds is ongoing due to factors such as low selectivity, high toxicity, and multidrug resistance. Thus, heterocyclic compounds derived from isatin, thiazole and phthalimide that have achieved promising in vitro anticancer activity have been tested in vivo and in clinical trials.

OBJECTIVE

This review focused on the compilation of promising data from thiazole, isatin, and phthalimide derivatives, reported in the literature between 2015 and 2022, with in vivo anticancer activity and clinical trials.

METHODS

A bibliographic search was carried out in the PUBMED, MEDLINE, ELSEVIER, and CAPES PERIODIC databases, selecting relevant works for each pharmacophoric group with in vivo antitumor activity in the last 6 years.

RESULTS

In our study, 68 articles that fit the scope were selected and critically analyzed. These articles were organized considering the type of antitumor activity and their year of publication. Some compounds reported here demonstrated potent antitumor activity against several tumor types.

CONCLUSION

This review allowed us to highlight works that reported promising structures for the treatment of various cancer types and also demonstrated that the privileged structures thiazole, isatin and phthalimide are important in the design of new syntheses and molecular optimization of compounds with antitumor activity.

Pyrazolo - Pyrimidines as Targeted Anticancer Scaffolds - A Comprehensive Review

BACKGROUND

Globally, cancer is the leading cause of death, which causes 10 million deaths yearly. Clinically, several drugs are used in treatment but due to drug resistance and multidrug resistance, there occurs a failure in the cancer treatment.

OBJECTIVES

The present review article is a comprehensive review of pyrazole and pyrimidine hybrids as potential anticancer agents.

METHODS

The review comprises more than 60 research works done in this field. The efficiency of the reported pyrazolopyrimidine fused heterocyclic with their biological data and the influence of the structural aspects of the molecule have been discussed.

RESULTS

This review highlighted pyrazolo-pyrimidines as targeted anticancer agents with effect on multiple targets.

CONCLUSION

The review will be helpful for the researchers involved in targeted drugs for cancer therapy for designing new scaffolds with pyrazolo-pyrimidine moieties.

1,3,4-Oxadiazole: An Emerging Scaffold to Inhibit the Thymidine Phosphorylase as an Anticancer Agent

Thymidine phosphorylase (TP), also referred to as "platelet-derived endothelial cell growth factor" is crucial to the pyrimidine salvage pathway. TP reversibly transforms thymidine into thymine and 2-deoxy-D-ribose-1-phosphate (dRib-1-P), which further degraded to 2-Deoxy-D-ribose (2DDR), which has both angiogenic and chemotactic activity. In several types of human cancer such as breast and colorectal malignancies, TP is abundantly expressed in response to biological disturbances like hypoxia, acidosis, chemotherapy, and radiation therapy. TP overexpression is highly associated with angiogenic factors such as vascular endothelial growth factor (VEGF), interleukins (ILs), matrix metalloproteases (MMPs), etc., which accelerate tumorigenesis, invasion, metastasis, immune response evasion, and resistant to apoptosis. Hence, TP is recognized as a key target for the development of new anticancer drugs. Heterocycles are the primary structural element of most chemotherapeutics. Even 75% of nitrogen-containing heterocyclic compounds are contributing to the pharmaceutical world. To create the bioactive molecule, medicinal chemists are concentrating on nitrogen-containing heterocyclic compounds such as pyrrole, pyrrolidine, pyridine, imidazole, pyrimidines, pyrazole, indole, quinoline, oxadiazole, benzimidazole, etc. The Oxadiazole motif stands out among all of them due to its enormous significance in medicinal chemistry. The main thrust area of this review is to explore the synthesis, SAR, and the significant role of 1,3,4-oxadiazole derivatives as a TP inhibitor for their chemotherapeutic effects.

Green Approach Toward Triazole Forming Reactions for Developing Anticancer Drugs

Compounds containing triazole have many significant applications in the dye and ink industry, corrosion inhibitors, polymers, and pharmaceutical industries. These compounds possess many antimicrobial, antioxidant, anticancer, antiviral, anti-HIV, antitubercular, and anticancer activities. Several synthetic methods have been reported for reducing time, minimizing synthetic steps, and utilizing less hazardous and toxic solvents and reagents to improve the yield of triazoles and their analogues synthesis. Among the improvement in methods, green approaches towards triazole forming biologically active compounds, especially anticancer compounds, would be very important for pharmaceutical industries as well as global research community. In this article, we have reviewed the last five years of green chemistry approaches on click reaction between alkyl azide and alkynes to install 1,2,3-triazole moiety in natural products and synthetic drug-like molecules, such as in colchicine, flavanone cardanol, bisphosphonates, thiabendazoles, piperazine, prostanoid, flavonoid, quinoxalines, C-azanucleoside, dibenzylamine, and aryl-azotriazole. The cytotoxicity of triazole hybrid analogues was evaluated against a panel of cancer cell lines, including multidrug-resistant cell lines.

An Insight into the Effect of Schiff Base and their d and f Block Metal Complexes on Various Cancer Cell Lines as Anticancer Agents: A Review

Over the last few decades, an alarming rise in the percentage of individuals with cancer and those with multi-resistant illnesses has forced researchers to explore possibilities for novel therapeutic approaches. Numerous medications currently exist to treat various disorders, and the development of small molecules as anticancer agents has considerable potential. However, the widespread prevalence of resistance to multiple drugs in cancer indicates that it is necessary to discover novel and promising compounds with ideal characteristics that could overcome the multidrug resistance issue. The utilisation of metallo-drugs has served as a productive anticancer chemotherapeutic method, and this approach may be implemented for combating multi-resistant tumours more successfully. Schiff bases have been receiving a lot of attention as a group of compounds due to their adaptable metal chelating abilities, innate biologic properties, and versatility to tweak the structure to optimise it for a specific biological purpose. The biological relevance of Schiff base and related complexes, notably their anticancer effects, has increased in their popularity as bio-inorganic chemistry has progressed. As a result of learning about Schiff bases antitumor efficacy against multiple cancer cell lines and their complexes, researchers are motivated to develop novel, side-effect-free anticancer treatments. According to study reports from the past ten years, we are still seeking a powerful anticancer contender. This study highlights the potential of Schiff bases, a broad class of chemical molecules, as potent anticancer agents. In combination with other anticancer strategies, they enhance the efficacy of treatment by elevating the cytotoxicity of chemotherapy, surmounting drug resistance, and promoting targeted therapy. Schiff bases also cause cancer cell DNA repair, improve immunotherapy, prevent angiogenesis, cause apoptosis, and lessen the side effects of chemotherapy. The present review explores the development of potential Schiff base and their d and f block metal complexes as anticancer agents against various cancer cell lines.

Design, synthesis and biological evaluation of new 1,ω-Bis-(5-alkyl-3-tosyl-1,3,4,2-triazaphospholino)alkanes as in vitro α-amylase and lipase inhibitors

A series of new 1,ω-bis-(5-alkyl-3-tosyl-1,3,4,2-triazaphospholino)alkanes 2 and 3 were obtained in excellent yields by the condensation of 1,ω-bis-(1-tosylamidrazone)alkanes 1 with two equivalent molars of Lawesson's Reagent (LR) and trisdimethylaminophosphine, respectively. All synthesized compounds were characterized by various spectroscopic techniques including IR, 1H NMR, 13C NMR and 31P NMR and elemental analysis. The newly synthesized compounds were evaluated against key enzymes related to diabetes and obesity such as α-amylase and lipase. This study showed that the compounds 3a and 2b are an excellent inhibitor of α-amylase (with IC50 = 18.8 mM) and lipase (with IC50 = 19 mM) respectively, as compared with standard, orlistat (IC50 = 22 mM). Among this series, compounds 3a and 2b with the CH3 or C2H5 group at position 6 were identified as the most potent inhibitors against α-amylase, and lipase enzymes. The remaining compounds were found to be moderately active. Further, molecular docking simulation studies were done to identify the interactions and binding mode of synthesized analogs at binding site of α-amylase and lipase enzymes.

New phenothiazine conjugates as apoptosis inducing agents: Design, synthesis, In-vitro anti-cancer screening and 131I-radiolabeling for in-vivo evaluation

Phenothiazines (PTZs) are a group of compounds characterized by the presence of the 10H-dibenzo-[b,e]-1,4-thiazine system. PTZs used in clinics as antipsychotic drugs with other diverse biological activities. The current aim of the study is to investigate and understand the effect of potent PTZs compounds using a group of In-vitro and In-vivo assays. A total of seventeen novel phenothiazine derivatives have been designed, synthesized, and evaluated primarily in-vitro for their ability to inhibit proliferation activity against NCI-60 cancer cell lines, including several multi-drug resistant (MDR) tumor cell lines. Almost all compounds were active and displayed promising cellular activities with GI50 values in the sub-micromolar range. Four of the most promising derivatives (4b, 4h, 4g and 6e) have been further tested against two selected sensitive cancer cell lines (colon cancer; HCT-116 and breast cancer; MDA-MB231). The apoptosis assay showed that all the selected compounds were able to induce early apoptosis and compound 6e was able to induce additional cellular necrosis. Cell cycle assay showed all selected compounds were able to induce cell cycle arrest at sub-molecular phase of G0-G1 with compound 6e induced cell cycle arrest at G2M in HCT-116 cells. Accordingly, the apoptotic effect of the selected compounds was extensively investigated on genetic level and Casp-3, Casp-9 and Bax gene were up-regulated with down-regulation of Bcl-2 gene suggesting the activation of both intrinsic and extrinsic pathways. In-vivo evaluation of the antitumor activity of compound 4b in solid tumor bearing mice showed promising therapeutic effect with manifestation of dose and time dependent toxic effects at higher doses. For better evaluation of the degree of localization of 4b, its 131I-congener (131I-4b) was injected intravenously in Ehrlich solid tumor bearing mice that showed good localization at tumor site with rapid distribution and clearance from the blood. In-silico study suggested NADPH oxidases (NOXs) as potential molecular target. The compounds introduced in the current study work provided a cutting-edge phenothiazine hybrid scaffold with promising anti-proliferation action that may suggest their anti-cancer activity.

Heterocyclic and non-heterocyclic arena of monocarboxylate transporter inhibitors to battle tumorigenesis

Monocarboxylate transporters (MCTs) have gained significant attention in cancer research due to their critical role in tumour metabolism. MCTs are legends for transporting lactate molecules in cancer cells, an oncometabolite and waste product of glycolysis, acting as an indispensable factor of tumour proliferation. Targeting MCTs with inhibitors has emerged as a promising strategy to combat tumorigenesis. This article summarizes the most recent research on MCT inhibitors in preventing carcinogenesis, covering both heterocyclic and non-heterocyclic compounds. Heterocyclic and non-heterocyclic compounds such as pteridine, pyrazole, indole, flavonoids, coumarin derivatives and cyanoacetic acid derivatives have been reported as potent MCT inhibitors. We examine the molecular underpinnings of MCTs in cancer metabolism, the design and synthesis of heterocyclic and non-heterocyclic MCT inhibitors, their impact on tumour cells and the microenvironment and their potential as therapeutic agents. Moreover, we explore the challenges associated with MCT inhibitor development and propose future directions for advancing this field. This write-up aims to provide researchers, scientists and clinicians with a comprehensive understanding of the heterocyclic and non-heterocyclic MCT inhibitors and their potential in combating tumorigenesis.

Synthesis and Biological Evaluation of 12-Aryl-11-hydroxy-5,6-dihydropyrrolo[2″,1″:3',4']pyrazino[1',2':1,5]pyrrolo[2,3-d]pyridazine-8(9H)-one Derivatives as Potential Cytotoxic Agents

In the present paper, a facile and efficient synthetic procedure has been applied to obtain dihydrodipyrrolo[1,2-a:2',1'-c]pyrazine-2,3-dicarboxylates (5a-s), which have subsequently gone through the cyclization in the presence of hydrazine hydrate to afford 12-aryl-11-hydroxy-5,6-dihydropyrrolo[2″,1″:3',4']pyrazino[1',2':1,5]pyrrolo[2,3-d]pyridazine-8(9H)-ones (7a-q). The molecular structures of these novel compounds were extensively examined through the analysis of spectroscopic data in combination with X-ray crystallography techniques. Following that, the in vitro cytotoxic activities of all derivatives against three human cancer cell lines (Panc-1, PC3, and MDA-MB-231) were comprehensively evaluated alongside the assessment on normal human dermal fibroblast (HDF) cells using the MTT assay. Among the compounds, the 3-nitrophenyl derivative (7m) from the second series showed the best antiproliferative activity against all tested cell lines, particularly against Panc-1 cell line, (IC50 = 12.54 μM), being nearly twice as potent as the standard drug etoposide. The induction of apoptosis and sub-G1 cell cycle arrest in Panc-1 cancer cells by compound 7m was confirmed through further assessment. Moreover, the inhibition of kinases and the induction of cellular apoptosis by compound 7m in Panc-1 cancer cells were validated using the Western blotting assay.

Visible-Light-Promoted Cascade Cyclization of 3-Ethynyl-[1,1'-biphenyl]-2-Carbonitriles with Unsaturated α-Bromocarbonyls

A visible-light-promoted cascade cyclization of 3-ethynyl-[1,1'-biphenyl]-2-carbonitriles with unsaturated α-bromocarbonyls for the synthesis of tetrahydrobenzo[mn]cyclopenta[b]acridines is described. Three C(sp3)-C(sp2) bonds, one C(sp2)-N bond, and three cycles can be formed in a single reaction through the addition of a C-centered radical to the carbon-carbon triple bond and three radical cyclizations. This reaction features mild conditions, wide substrate scope, and high bond-forming efficiency.

Antitumor activity against human promyelocytic leukemia and in silico studies of some benzoxazines

Cancer is one of the deadliest diseases in the world today, and the incidence of cancer is increasing. Leukemia is a type of blood cancer defined as the uncontrolled proliferation of abnormal leukocytes in the blood and bone marrow. The HL-60 (human promyelocytic leukemia) cell line, derived from a single patient with acute promyelocytic leukemia, provides a unique in vitro model system for studying the cellular and molecular events involved in the proliferation and differentiation of leukemic cells. In this study, antitumor activities on the HL-60 of some of the resynthesized benzoxazine derivatives (BXN-01 and BXN-02) were investigated. The results of in vitro studies obtained were compared a standard drug, etoposide. In vitro results showed that BXN-01 and BXN-02 were found to be extremely effective compared to etoposide (IC50 value: 10 µM) with IC50 values of 5 nM and 25 nM, respectively. Furthermore, molecular docking studies were carried out for preliminary prediction of possible interaction modes between compounds and the active site of the target macromolecules, hTopo IIα, HDAC2, and RXRA. Then, in silico ADME/Tox studies were performed to predict drug-likeness and pharmacokinetic properties of BXN-01 and BXN-02.Communicated by Ramaswamy H. Sarma.

Synthesis and Biological Studies of Benzo[b]furan Derivatives: A Review from 2011 to 2022

The importance of the benzo[b]furan motif becomes evident in the remarkable results of numerous biological investigations, establishing its potential as a robust therapeutic option. This review presents an overview of the synthesis of and exhaustive biological studies conducted on benzo[b]furan derivatives from 2011 to 2022, accentuating their exceptional promise as anticancer, antibacterial, and antifungal agents. Initially, the discussion focuses on chemical synthesis, molecular docking simulations, and both in vitro and in vivo studies. Additionally, we provide an analysis of the intricate interplay between structure and activity, thereby facilitating comparisons and profoundly emphasizing the applications of the benzo[b]furan motif within the realms of drug discovery and medicinal chemistry.

Pyrazolo[4,3-e]tetrazolo[1,5-b][1,2,4]triazine Sulfonamides as an Important Scaffold for Anticancer Drug Discovery-In Vitro and In Silico Evaluation

Pyrazolo[4,3-e]tetrazolo[1,5-b][1,2,4]triazine sulfonamides (MM-compounds) are a relatively new class of heterocyclic compounds that exhibit a wide variety of biological actions, including anticancer properties. Here, we used caspase enzyme activity assays, flow cytometry analysis of propidium iodide (PI)-stained cells, and a DNA laddering assay to investigate the mechanisms of cell death triggered by the MM-compounds (MM134, -6, -7, and -9). Due to inconsistent results in caspase activity assays, we have performed a bromodeoxyuridine (BrdU) incorporation assay, colony formation assay, and gene expression profiling. The compounds' cytotoxic and pro-oxidative properties were also assessed. Additionally, computational studies were performed to demonstrate the potential of the scaffold for future drug discovery endeavors. MM-compounds exhibited strong micromolar (0.06-0.35 µM) anti-proliferative and pro-oxidative activity in two cancer cell lines (BxPC-3 and PC-3). Activation of caspase 3/7 was observed following a 24-h treatment of BxPC-3 cells with IC₅₀ concentrations of MM134, -6, and -9 compounds. However, no DNA fragmentation characteristics for apoptosis were observed in the flow cytometry and DNA laddering analysis. Gene expression data indicated up-regulation of BCL10, GADD45A, RIPK2, TNF, TNFRSF10B, and TNFRSF1A (TNF-R1) following treatment of cells with the MM134 compound. Moreover, in silico studies indicated AKT2 kinase as the primary target of compounds. MM-compounds exhibit strong cytotoxic activity with pro-oxidative, pro-apoptotic, and possibly pro-necroptotic properties that could be employed for further drug discovery approaches.

Novel Acylselenourea Derivatives: Dual Molecules with Anticancer and Radical Scavenging Activity

Oxidative stress surrounding cancer cells provides them with certain growth and survival advantages necessary for disease progression. In this context, Se-containing molecules have gained attention due to their anticancer and antioxidant activity. In our previous work, we synthesized a library of 39 selenoesters containing functional groups commonly present in natural products (NP), which showed potent anticancer activity, but did not demonstrate high radical scavenger activity. Thus, 20 novel Se derivatives resembling NP have been synthesized presenting acylselenourea functionality in their structures. Radical scavenger activity was tested using DPPH assay and in vitro protective effects against ROS-induced cell death caused by H₂O₂. Additionally, antiproliferative activity was evaluated in prostate, colon, lung, and breast cancer cell lines, along with their ability to induce apoptosis. Compounds 1.I and 5.I showed potent cytotoxicity against the tested cancer cell lines, along with high selectivity indexes and induction of caspase-mediated apoptosis. These compounds exhibited potent and concentration-dependent radical scavenging activity achieving DPPH inhibition similar to ascorbic acid and trolox. To conclude, we have demonstrated that the introduction of Se in the form of acylselenourea into small molecules provides strong radical scavengers in vitro and antiproliferative activity, which may lead to the development of promising dual compounds.

Highly regioselective and diastereoselective synthesis of novel pyrazinoindolones via a base-mediated Ugi-N-alkylation sequence

An efficient base-mediated/metal-free approach has been developed for the synthesis of 1-oxo-1,2,3,4-tetrahydropyrazino[1,2-a]indole-3-carboxamide derivatives via intramolecular indole N-H alkylation of novel bis-amide Ugi-adducts. In this protocol the Ugi reaction of (E)-cinnamaldehyde derivatives, 2-chloroaniline, indole-2-carboxylic acid and different isocyanides was designed for the preparation of bis-amides. The main highlight of this study is the practical and highly regioselective preparation of new polycyclic functionalized pyrazino derivatives. This system is facilitated by Na₂CO₃ mediation in DMSO and 100 °C conditions.

An overview of structure-based activity outcomes of pyran derivatives against Alzheimer's disease

Pyran is a heterocyclic group containing oxygen that possesses a variety of pharmacological effects. Pyran is also one of the most prevalent structural subunits in natural products, such as xanthones, coumarins, flavonoids, benzopyrans, etc. Additionally demonstrating the neuroprotective properties of pyrans is the fact that this heterocycle has recently attracted the attention of scientists worldwide. Alzheimer's Disease (AD) treatment and diagnosis are two of the most critical research objectives worldwide. Increased amounts of extracellular senile plaques, intracellular neurofibrillary tangles, and a progressive shutdown of cholinergic basal forebrain neuron transmission are often related with cognitive impairment. This review highlights the various pyran scaffolds of natural and synthetic origin that are effective in the treatment of AD. For better understanding synthetic compounds are categorized as different types of pyran derivatives like chromene, flavone, xanthone, xanthene, etc. The discussion encompasses both the structure-activity correlations of these compounds as well as their activity against AD. Because of the intriguing actions that were uncovered by these pyran-based scaffolds, there is no question that they are at the forefront of the search for potential medication candidates that could treat Alzheimer's disease.

New indoleacetic acid-functionalized soluble oxidized starch-based nonionic biopolymers as natural antibacterial materials

This study aims to develop a new soluble oxidized starch-based nonionic antibacterial polymer (OCSI) featuring high antibacterial activity and non-leachability by grafting indoleacetic acid monomer (IAA) onto the oxidized corn starch (OCS). The synthesized OCSI was characterized analytically by Nuclear magnetic resonance H-spectrometer (¹H NMR), Fourier transform infrared spectroscopy (FTIR), Ultraviolet-visible spectroscopy (UV-Vis), X-ray diffractometer (XRD), X-ray Photoelectron Spectroscopy (XPS), Scanning Electronic Microscopy (SEM), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The results showed that the synthesized OCSI was endowed with high thermal stability and favorable solubility, and the substitution degree reached 0.6. Besides, the disk diffusion test revealed a lowest OCSI inhibitory concentration of 5 μg disk^-1, and showed significant bactericidal activity against Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli). Moreover, the antibacterial films (OCSI-PCL), featuring their good compatibility, mechanical properties, antibacterial activity, non-leachability, and low water vapor permeability (WVP), were also successfully prepared by blending OCSI with biodegradable polycaprolactone (PCL). Finally, CCK-8 assay results confirmed the excellent biocompatibility of the OCSI-PCL films. Overall, this very study evidenced the applicability of the obtained oxidized starch-based biopolymers as an eco-friendly non-ionic antibacterial material and confirmed their promising applications in areas including biomedical materials, medical devices, and food packaging.

DeepAR: a novel deep learning-based hybrid framework for the interpretable prediction of androgen receptor antagonists

Drug resistance represents a major obstacle to therapeutic innovations and is a prevalent feature in prostate cancer (PCa). Androgen receptors (ARs) are the hallmark therapeutic target for prostate cancer modulation and AR antagonists have achieved great success. However, rapid emergence of resistance contributing to PCa progression is the ultimate burden of their long-term usage. Hence, the discovery and development of AR antagonists with capability to combat the resistance, remains an avenue for further exploration. Therefore, this study proposes a novel deep learning (DL)-based hybrid framework, named DeepAR, to accurately and rapidly identify AR antagonists by using only the SMILES notation. Specifically, DeepAR is capable of extracting and learning the key information embedded in AR antagonists. Firstly, we established a benchmark dataset by collecting active and inactive compounds against AR from the ChEMBL database. Based on this dataset, we developed and optimized a collection of baseline models by using a comprehensive set of well-known molecular descriptors and machine learning algorithms. Then, these baseline models were utilized for creating probabilistic features. Finally, these probabilistic features were combined and used for the construction of a meta-model based on a one-dimensional convolutional neural network. Experimental results indicated that DeepAR is a more accurate and stable approach for identifying AR antagonists in terms of the independent test dataset, by achieving an accuracy of 0.911 and MCC of 0.823. In addition, our proposed framework is able to provide feature importance information by leveraging a popular computational approach, named SHapley Additive exPlanations (SHAP). In the meanwhile, the characterization and analysis of potential AR antagonist candidates were achieved through the SHAP waterfall plot and molecular docking. The analysis inferred that N-heterocyclic moieties, halogenated substituents, and a cyano functional group were significant determinants of potential AR antagonists. Lastly, we implemented an online web server by using DeepAR (at http://pmlabstack.pythonanywhere.com/DeepAR ). We anticipate that DeepAR could be a useful computational tool for community-wide facilitation of AR candidates from a large number of uncharacterized compounds.

5,6,7,8-Tetra-hydro-[1,2,4]triazolo[5,1-b]quinazolin-9(4H)-one

The triazole ring in the title mol-ecule, C₉H₁₀N₄O, is not quite coplanar with the six-membered ring to which it is fused, the dihedral angle between the two least-squares planes being 2.52 (6)°. In the crystal, a layered structure is formed by N-H⋯N and C-H⋯O hydrogen bonds plus slipped π-stacking inter-actions, with the fused cyclo-hexene rings projecting to either side.

Designing of thiazolidinones against chicken pox, monkey pox, and hepatitis viruses: A computational approach

Computational designing of four different series (D-G) of thiazolidinone was done starting from different amines which was further condensed with various aldehydes. These underwent in silico molecular investigations for density functional theory (DFT), molecular docking, and absorption, distribution metabolism, excretion, and toxicity (ADMET) studies. The different electrochemical parameters of the compounds are predicted using quantum mechanical modeling approach with Gaussian. The docking software was used to dock the compounds against choosing PDB file for chickenpox, human immunodeficiency, hepatitis, and monkeypox virus as 1OSN, 1VZV, 6VLK, 1RTD, 3I7H, 3TYV, 4JU3, and 4QWO, respectively. The molecular interactions were visualized with discovery studio and maximum binding affinity was observed with D8 compounds against 4QWO (-13.383 kcal/mol) while for compound D5 against 1VZV which was -12.713 kcal/mol. Swiss ADME web tool was used to assess the drug-likeness of the designed compounds under consideration, and it is concluded that these molecules had a drug-like structure with almost zero violations.

Recent Advances in Synthetic Routes to Azacycles

A heterocycle is an important structural scaffold of many organic compounds found in pharmaceuticals, materials, agrochemicals, and biological processes. Azacycles are one of the most common motifs of a heterocycle and have a variety of applications, including in pharmaceuticals. Therefore, azacycles have received significant attention from scientists and a variety of methods of synthesizing azacycles have been developed because their efficient synthesis plays a vital role in the production of many useful compounds. In this review, we summarize recent approaches to preparing azacycles via different methods as well as describe plausible reaction mechanisms.

Nitroarenes and nitroalkenes as potential amino sources for the synthesis of N-heterocycles

Nitro-compounds are one of the cheapest and most readily available materials in the chemical industry and are commonly utilized as versatile building blocks. Previously, the synthesis of N-heterocycles was largely based on anilines. The utilization of nitroarenes and nitroalkenes for the synthesis of N-heterocyclic compounds can save at least one step, however, as compared to anilines. Thus, considerable attention has been paid to nitroarenes and nitroalkenes as new potential amino sources. Significant progress has been made in the reductive cyclization of nitroarenes or nitroalkenes to access various N-heterocycles in recent years. Herein, we comprehensively summarize the recent progress in the construction of N-heterocycles using nitroarenes and nitroalkenes as potential amino sources. The compatibility of the reaction substrate, its mechanism, applications, advantages, and limitations in this field are also discussed in detail.

New AB3-type porphyrins with piperidine and morpholine motifs; synthesis and photo-physicochemical and biological properties

In this study, new unsymmetrical meso-tetraaryl AB₃-type porphyrins 1 and 2 were successfully synthesized by the reaction of p-bromobenzaldehyde and p-hydroxybenzaldehyde with pyrrole in propionic acid. AB₃-type porphyrin building blocks with hydroxyl functionality (1 and 2) were further used to generate both covalently linked metal free and Zn(II) porphyrins 3-6 having piperidine and morpholine heterocyclic units. These novel compounds were characterized by using ¹H NMR, ¹³C NMR, FT-IR and MALDI-TOF spectrophotometry. The photophysical and photochemical properties of compounds 1-6 were investigated by employing UV-vis absorption and fluorescence emission spectroscopy in tetrahydrofuran (THF). From the view of biological properties, the antioxidant capacities of porphyrins were determined by using DPPH radical scavenging activity and 2 was determined as the most potent porphyrin analog with a value of 98.42% at 200 mg L^-1. All the targeted compounds displayed significant DNA nuclease activity. In addition, the antimicrobial potential of compounds 1-6 was also investigated by a micro-dilution process and 2 was found to be the most effective candidate against the tested microbial strains. The newly synthesized porphyrins also showed 100% microbial cell viability inhibition against E. coli at all examined concentrations. In terms of biofilm inhibition activity, the best results for the maximum photodynamic antimicrobial biofilm inhibition of S. aureus and P. aeruginosa were obtained by compound 2 with the values of 99.75% and 93.39%, respectively.

A Novel Ambroxol-Derived Tetrahydroquinazoline with a Potency against SARS-CoV-2 Proteins

We report synthesis of a novel 1,2,3,4-tetrahydroquinazoline derivative, named 2-(6,8-dibromo-3-(4-hydroxycyclohexyl)-1,2,3,4-tetrahydroquinazolin-2-yl)phenol (1), which was obtained from the hydrochloride of 4-((2-amino-3,5-dibromobenzyl)amino)cyclohexan-1-ol (ambroxol hydrochloride) and salicylaldehyde in EtOH. The resulting compound was produced in the form of colorless crystals of the composition 1∙0.5EtOH. The formation of the single product was confirmed by the IR and 1H spectroscopy, single-crystal and powder X-ray diffraction, and elemental analysis. The molecule of 1 contains a chiral tertiary carbon of the 1,2,3,4-tetrahydropyrimidine fragment and the crystal structure of 1∙0.5EtOH is a racemate. Optical properties of 1∙0.5EtOH were revealed by UV-vis spectroscopy in MeOH and it was established that the compound absorbs exclusively in the UV region up to about 350 nm. 1∙0.5EtOH in MeOH exhibits dual emission and the emission spectra contains bands at about 340 and 446 nm upon excitation at 300 and 360 nm, respectively. The DFT calculations were performed to verify the structure as well as electronic and optical properties of 1. ADMET properties of the R-isomer of 1 were evaluated using the SwissADME, BOILED-Egg, and ProTox-II tools. As evidenced from the blue dot position in the BOILED-Egg plot, both human blood-brain barrier penetration and gastrointestinal absorption properties are positive with the positive PGP effect on the molecule. Molecular docking was applied to examine the influence of the structures of both R-isomer and S-isomer of 1 on a series of the SARS-CoV-2 proteins. According to the docking analysis results, both isomers of 1 were found to be active against all the applied SARS-CoV-2 proteins with the best binding affinities with Papain-like protease (PLpro) and nonstructural protein 3 (Nsp3_range 207-379-AMP). Ligand efficiency scores for both isomers of 1 inside the binding sites of the applied proteins were also revealed and compared with the initial ligands. Molecular dynamics simulations were also applied to evaluate the stability of complexes of both isomers with Papain-like protease (PLpro) and nonstructural protein 3 (Nsp3_range 207-379-AMP). The complex of the S-isomer with Papain-like protease (PLpro) was found to be highly unstable, while the other complexes are stable.

Recent advances of LSD1/KDM1A inhibitors for disease therapy

Lysine-specific demethylase 1 (LSD1/KDM1A) dysregulation is closely associated with the pathological processes of various diseases, especially hematologic malignancies. Significant progresses have been made in the field of LSD1-targeted drug discovery. Nine LSD1 inhibitors including tranylcypromine, ORY-1001, ORY-2001, GSK-2879552, IMG-7289, INCB059872, TAK-418, CC-90011 and SP-2577 have entered clinical stage for disease treatment as either mono- or combinational therapy. This review updates LSD1 inhibitors reported during 2022. Design strategies, structure-activity relationship studies, binding model analysis and modes of action are highlighted. In particular, the unique multiple-copies binding mode of quinazoline derivatives paves new ways for the development of reversible LSD1 inhibitors by blocking the substrate entrance. The design strategy of clinical candidate TAK-418 also provides directions for further optimization of novel irreversible LSD1 inhibitors with low hematological side effects. The influence of the stereochemistry on the potency against LSD1 and its homolog LSD2 is briefly discussed. Finally, the challenges and prospects of LSD1-targeted drug discovery are also given.