Synthesis, cytotoxic activity and docking studies of new 4-aza-podophyllotoxin derivatives

Multicomponent Reactions Using C,N-Binucleophilic Nature of Aminopyrazoles: Construction of Pyrazole-Fused Heterocycles

Synthesis of pyrazole-fused heterocycles has gained considerable attention in recent years due to their wide applications in medicinal chemistry. Aminopyrazoles are versatile building blocks for the synthesis of pyrazole-fused heterocycles by multicomponent reactions. Due to the presence of multiple reaction sites, they have fascinating chemical reactivity. Thus, they have been extensively used in multicomponent reactions for the construction of pyrazole-fused heterocycles. Although few review articles on the preparation and applications of aminopyrazoles are known in the literature, to date there is no dedicated review article on the construction of pyrazole-fused heterocycles exploring the reactivity of amino pyrazoles as C,N-binucleophiles in multicomponent reactions. Considering this, herein the multicomponent reactions for the construction of pyrazole-fused heterocycles exploring C,N-binucleophilic nature of amino pyrazoles have been reported.

Synthesis and medicinal chemistry of tetronamides: Promising agrochemicals and antitumoral compounds

Butenolides and tetronic acids occupy a prominent position in synthetic chemistry due to their ubiquitous distribution in nature. This has stimulated investigations firstly in the synthesis of such systems and, laterly, the interest has turned to the understanding of the quantum structure of such systems, allowing a deeper understanding of the mechanism and reactivity of this cyclic scaffold. In contrast, tetronamides, which consist of compounds bearing a 4-aminofuran-2(5H)-one backbone, are relatively rare in nature and synthetic routes to such compounds are poorly explored. This review highlights both the importance of the tetronamide scaffold in medicinal chemistry and the most relevant recondite synthetic strategies for obtaining compounds of this class.

Synthesis, cytotoxicity, and molecular docking of methylated (–)-epigallocatechin-3-gallate-4β-triazolopodophyllotoxin derivatives as novel antitumor agents

A series of novel methylated (–)-epigallocatechin-3-gallate-4β-triazolopodophyllotoxin derivatives is synthesized by utilizing the click reaction. Evaluation of their cytotoxicity against a panel of five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW480) using the MTT assay shows that most of these compounds exhibit weak cytotoxicity. It is observed that compound 12 shows the highest activity against A-549 cells with an IC50 value of 10.27 ± 0.90 μM. Molecular docking results suggested that this compound 12 has a higher binding affinity for epidermal growth factor receptor than for tubulin. Our findings support the utility of compound 12 as a novel compound for the further development of anticancer agents.

Artificial Intelligence, Big Data and Machine Learning Approaches in Precision Medicine & Drug Discovery

Artificial Intelligence revolutionizes the drug development process that can quickly identify potential biologically active compounds from millions of candidate within a short period. The present review is an overview based on some applications of Machine Learning based tools, such as GOLD, Deep PVP, LIB SVM, etc. and the algorithms involved such as support vector machine (SVM), random forest (RF), decision tree and Artificial Neural Network (ANN), etc. at various stages of drug designing and development. These techniques can be employed in SNP discoveries, drug repurposing, ligand-based drug design (LBDD), Ligand-based Virtual Screening (LBVS) and Structure- based Virtual Screening (SBVS), Lead identification, quantitative structure-activity relationship (QSAR) modeling, and ADMET analysis. It is demonstrated that SVM exhibited better performance in indicating that the classification model will have great applications on human intestinal absorption (HIA) predictions. Successful cases have been reported which demonstrate the efficiency of SVM and RF models in identifying JFD00950 as a novel compound targeting against a colon cancer cell line, DLD-1, by inhibition of FEN1 cytotoxic and cleavage activity. Furthermore, a QSAR model was also used to predict flavonoid inhibitory effects on AR activity as a potent treatment for diabetes mellitus (DM), using ANN. Hence, in the era of big data, ML approaches have been evolved as a powerful and efficient way to deal with the huge amounts of generated data from modern drug discovery to model small-molecule drugs, gene biomarkers and identifying the novel drug targets for various diseases.

Design, Synthesis, and Biological Evaluation of 1,2,4-Thiadiazole-1,2,4-Triazole Derivatives Bearing Amide Functionality as Anticancer Agents

A novel library of amide functionality having 1,2,4-thiadiazole-1,2,4-triazole (8a–j) analogs was designed, synthesized, and structures were characterized by ¹H NMR, ¹³C NMR, and mass (ESI–MS) spectral data. Further, all compounds were evaluated for their anticancer activities against four different cancer cell lines including breast cancer (MCF-7, MDA MB-231), lung cancer (A549), and prostate cancer (DU-145) by MTT reduction assay method, and etoposide acts as a standard drug. The results confirmed that majority of the synthesized compounds showed moderate to potent anticancer activities aligned with four cell lines. Among the synthesized compounds, 8b, 8c, 8d, 8e, 8g and 8i displayed more potent activity along with inhibitory concentration values ranging from 0.10 ± 0.084 to 11.5 ± 6.49 µM than the standard IC₅₀ values, which ranges from 1.91 ± 0.84 to 3.08 ± 0.135 µM, respectively.

Novel 1,3,4-Oxadiazole Fused Thiadiazole Derivatives: Synthesis and study of Anticancer Activities

Background:

In search of novel anticancer agents, a series of 1,3,4-oxadiazole derivatives (12a-j) containing 1,3,4-thiadiazole moieties were synthesized, and their structures were confirmed by 1HNMR, 13CNMR and ESI-MS spectral analysis.

Methods:

Cytotoxicity of these compounds was evaluated by MTT assay in vitro against four human tumor cell lines, i.e. A549 (lung), MCF-7 (breast), A375 (melanoma) and HT-29 (colon).

Results:

Here, CA4 used as positive control. Among them, compounds 12b, 12c, 12f, 12g, 12h and 12j were exhibited promising activity than control drug.

Conclusion:

In conclusion, we have synthesized a novel series of 1,3,4-oxadiazole fused 1,3,4- thiazdiazole derivatives and their structures were confirmed by spectral analysis.

A comprehensive review of topoisomerase inhibitors as anticancer agents in the past decade

The topoisomerase enzymes play an important role in DNA metabolism, and searching for enzyme inhibitors is an important target in the search for new anticancer drugs. Discovery of new anticancer chemotherapeutical capable of inhibiting topoisomerase enzymes is highlighted in anticancer research. Therefore, biologists, organic chemists and medicinal chemists all around the world have been identifying, designing, synthesizing and evaluating a variety of novel bioactive molecules targeting topoisomerase. This review summarizes types of topoisomerase inhibitors in the past decade, and divides them into nine classes by structural characteristics, including N-heterocycles compounds, quinone derivatives, flavonoids derivatives, coumarin derivatives, lignan derivatives, polyphenol derivatives, diterpenes derivatives, fatty acids derivatives, and metal complexes. Then we discussed the application prospect and development of these anticancer compounds, as well as concluded parts of their structural-activity relationships. We believe this review would be invaluable in helping to further search potential topoisomerase inhibition as antitumor agent in clinical usage.

Synthesis, antiproliferative and apoptosis induction potential activities of novel bis(indolyl)hydrazide-hydrazone derivatives

In recent years, indole-indazolyl hydrazide-hydrazone derivatives with strong cell growth inhibition and apoptosis induction characteristics are being strongly screened for their cancer chemo-preventive potential. In the present study, N-methyl and N,N-dimethyl bis(indolyl)hydrazide-hydrazone analog derivatives were designed, synthesized and allowed to evaluate for their anti-proliferative and apoptosis induction potential against cervical (HeLa), breast (MCF-7 and MDA-MB-231) and lung (A549) cancer cell lines relative to normal HEK293 cells. The MTT assay in conjunction with mitochondrial potential assays and the trypan blue dye exclusion were employed to ascertain the effects of the derivatives on the cancer cells. Further, mechanistic studies were conducted on compound 14a to understand the biochemical mechanisms and functional interactions with various signaling pathways triggered in HeLa and MCF-7 cells. Compound 14a induced apoptosis via caspase independent pathway through the participation of mitogen-activated protein kinases (MAPK) such as extracellular signal related kinase (ERK) and p38 as well as p53 pathways. It originates the activation of pro-apoptotic proteins such as Bak and Mcl-1s and also strongly induced the generation of reactive oxygen species. In downstream signaling pathway, activated p53 protein interacted with MAPK pathways, including SAPK/c-Jun N-terminal protein kinase (JNK), p38 and ERK kinases resulting in apoptotic cell death. The involvement of MAPK cascades such as p38, ERK and p38 on compound 14a induced apoptotic cell death was evidenced by the fact that the inclusion of specific inhibitors of p38, ERK1/2 and JNK MAPK (SB2035809, PD98059 and SP600125) prevented the compound 14a towards induced apoptosis. The results clearly showed that MAP kinase cascades were crucial for apoptotic response in compound 14a induced cellular killing and were dependent on p53 activity. Based on the results, compound 14a was identified as a promising candidate for cancer therapeutics and these findings furnish a basis for further in vivo experiments on anti-proliferative activity.

5-Amino-pyrazoles: potent reagents in organic and medicinal synthesis

5-Amino-pyrazoles have proven to be a class of fascinating and privileged organic tools for the construction of diverse heterocyclic or fused heterocyclic scaffolds. This review presents comprehensively the applications of 5-amino-pyrazoles as versatile synthetic building blocks in the synthesis of remarkable organic molecules with an emphasis on versatile functionalities. Following a brief introduction of synthesis methods, planning strategies to construct organic compounds, particularly diverse heterocyclic scaffolds, such as poly-substituted heterocyclic compounds and fused heterocyclic compounds via 5-amino-pyrazoles, have been summarized. Fused heterocycles are classified as bicyclic, tricyclic, tetracyclic, and spiro-fused pyrazole derivatives. These outstanding compounds synthesized via wide variety of approaches include conventional reactions, one-pot multi-component reactions, cyclocondensation, cascade/tandem protocols, and coupling reactions. 5-Amino-pyrazoles represent a class of promising functional reagents, similar to the biologically active compounds, highlighted with diverse applications especially in the field of pharmaceutics and medicinal chemistry. Notably, this critical review covers the articles published from 1981 to 2018.

Aminoazole-Based Diversity-Oriented Synthesis of Heterocycles

The comprehensive review contains the analysis of literature data concerning reactions of heterocyclization of aminoazoles and demonstrates the application of these types of transformations in diversity-oriented synthesis. The review is oriented to wide range of chemists working in the field of organic synthesis and both experimental and theoretical studies of nitrogen-containing heterocycles.

One-Pot Synthesis of Densely Substituted Pyrazolo[3,4-b]-4,7-dihydropyridines

We have achieved a facile synthesis of a combinatorial library of densely substituted pyrazolo[3,4-b]-4,7-dihydropyridines- the mimics of antigenital wart drug podophyllotoxin-from 5-aminopyrazoles and 4-(methylthio) 4H-chromenes. The C(4) pyrazolyl 4H-chromenes, which also possess structural features of podophyllotoxin, were isolable intermediates in the two-step, one-pot condensation. The condensation took place in a one-pot, multicomponent manner when 3-oxo-3-phenylpropanenitriles, hydrazine (precursors for 5-aminopyrazoles) and 4-(methylthio)-4H-chromenes were heated in refluxing ethanol. The condensation, however, stops at 4H-chromene stage when methyl hydrazine or phenylhydrazine were employed. Our findings offer an opportunity for synthesis of a combinatorial library of podophyllotoxin mimics, thus paving the way for discovery of lead candidates for cancer treatment.

Syntheses and anti-inflammatory activity of azamollugin derivatives

Oxomollugin (2) is a degradation product of mollugin (1) and a potent inhibitor of NO-production including nuclear factor kappa B signals. In our endeavor to develop a potent anti-inflammatory compound, we synthesized several aza-derivatives of oxomollugin (2) and evaluated their NO-production inhibitory activity. Azamollugin (3) showed a potent inhibitory activity, and its activity (IC50 0.34μM) was proved to be more potent than that of oxomollugin (2, IC50 1.3μM).