Synthesis, antitumor and DNA photocleaving activities of novel naphthalene carboxamides: effects of different thio-heterocyclic rings and aminoalkyl side chains

A Comprehensive Review on Fused Heterocyclic as DNA Intercalators: Promising Anticancer Agents

Since the discovery of DNA intercalating agents (by Lerman, 1961), a growing number of organic, inorganic, and metallic compounds have been developed to treat life-threatening microbial infections and cancers. Fused-heterocycles are amongst the most important group of compounds that have the ability to interact with DNA. DNA intercalators possess a planar aromatic ring structure that inserts itself between the base pairs of nucleic acids. Once inserted, the aromatic structure makes van der Waals interactions and hydrogen-bonding interactions with the base pairs. The DNA intercalator may also contain an ionizable group that can form ionic interactions with the negatively charged phosphate backbone. After the intercalation, other cellular processes could take place, leading ultimately to cell death. The heterocyclic nucleus present in the DNA intercalators can be considered as a pharmacophore that plays an instrumental role in dictating the affinity and selectivity exhibited by these compounds. In this work, we have carried out a revision of small organic molecules that bind to the DNA molecule via intercalation and cleaving and exert their antitumor activity. A general overview of the most recent results in this area, paying particular attention to compounds that are currently under clinical trials, is provided. Advancement in spectroscopic techniques studying DNA interaction can be examined in-depth, yielding important information on structure-activity relationships. In this comprehensive review, we have focused on the introduction to fused heterocyclic agents with DNA interacting features, from medicinal point of view. The structure-activity relationships points, cytotoxicity data, and binding data and future perspectives of medicinal compounds have been discussed in detail.

Naphthalene, a versatile platform in medicinal chemistry: Sky-high perspective

Naphthalene, a cytotoxic moiety, is an extensively explored aromatic conjugated system with applications in various pathophysiological conditions viz. anticancer, antimicrobial, anti-inflammatory, antiviral, antitubercular, antihypertensive, antidiabetic, anti-neurodegenerative, antipsychotic, anticonvulsant, antidepressant. Naphthalene epoxides and naphthoquinones are most reactive metabolites of naphthalene and are responsible for the covalent interaction with cysteine amino acid of cellular proteins for cytotoxic nature. Many naphthalene derived bioactive phytoconstituents are present in nature including podophyllotoxins (Etoposide, teniposide), bis-ANS 82, Rifampicin, Justiprocumin A, B, Patentiflorin A. The naphthalene-based molecules, viz. Naphyrone, tolnaftate, naftifine, nafcillin, terbinafine, propranolol, nabumetone, nafimidone, naproxen, duloxetine, lasofoxifene, bedaquiline etc. have also been approved by FDA and are being marketed as therapeutics. Thus, the naphthalene scaffold emerges as an important building block in drug discovery owing to its broad spectrum of biological activities through varying structural modifications. This review incorporates the pharmacological aspects of different types of chemically modified naphthalene-based molecules along with their activity profile. This compiled information may serve as a benchmark for the alteration of existing ligands to design novel potent molecules with lesser side effects.

A novel triazolonaphthalimide induces apoptosis and inhibits tumor growth by targeting DNA and DNA-associated processes

DNA and DNA-associated processes have been classes of the most important targets of chemotherapeutic drugs. As classic DNA intercalators and topoisomerase inhibitors, naphthalimides have been extensively investigated as potential anti-cancer drugs. We recently synthesized a novel series of triazolonaphthalimides with excellent anti-cancer activities. In the present study, one of the most potent triazolonaphthalimides, LSS-11, was investigated. LSS-11 bound to DNA in vitro and in cell mainly by minor groove binding and significantly increased the stability of DNA, which could be fundamental for the biological activities of LSS-11. In addition to inhibiting DNA topoisomerase II-catalyzed decatenation of knotted circulated DNA, LSS-11 dramatically inhibited DNA replication mediated by polymerase chain reaction and isothermal helicase-dependent amplification, as well as the expression of luciferase driven by a minimal TA promoter in cell. Furthermore, LSS-11 exhibited strong cytotoxicity in selected human colon cancer cell lines by inducing cell cycle arrest and apoptosis, which was accompanied by DNA damage response. Finally, LSS-11 potently inhibited the growth of S180 murine sarcoma and SW480 human colorectal cancer xenografts in vivo without significant major toxicities. These results suggest that LSS-11 deserves further research and development as a novel anti-cancer agent, and provided new understandings of mechanisms by which LSS-11 inhibited multiple DNA-associated processes and tumor growth.

Synthesis, DNA interaction and anticancer activity of 2-anthryl substituted benzimidazole derivatives

2-Anthryl substituted benzimidazole derivatives were synthesized and anticancer activity, cellular uptake, DNA interaction and molecular docking studies have been accomplished.

Synthesis of alpha-ketoester- and alpha-hydroxyester-substituted isoindazoles via the thermodynamic coarctate cyclization of ester-terminated azo-ene-yne systems

The synthesis of isoindazoles bearing alpha-ketoester and alpha-hydroxyester groups via the coarctate cyclization of ester-terminated azo-ene-yne precursors is described. Whereas previous studies on isoindazole formation have shown the reaction to proceed through a kinetic coarctate pathway, functionalization of the terminal acetylene with a methyl ester sufficiently stabilizes the carbene intermediate to make the coarctate cyclization the thermodynamic pathway. Density functional theory (DFT) computations reveal ca. 8-9 kcal mol(-1) lower energy transition states for the coarctate pathway compared to the parent system.

Highly efficient antitumor agents of heterocycles containing sulfur atom: Linear and angular thiazonaphthalimides against human lung cancer cell in vitro

A novel series of aminothiazonaphthalimides, A(1-2) and B(1-2), has been regioselectively synthesized. The linear compounds B(1-2) were evaluated to be far more active than their angular isomers A(1-2) in antitumor evaluation. The linear compounds C-F, derived from compound B(1), all showed highly efficient antitumor activities against A549 and P388 cell lines. Also, cytotoxicities of these four analogues against two tumor cells were highly dependent on the length of the side chains. The compound A(1) or B(1), with two methylene units in the side chain, was more cytotoxic than its corresponding homologue A(2) or B(2), with one more methylene unit.

Design, syntheses, and antitumor activity of novel chromone and aurone derivatives

A series of new chromone analogues bearing heterocyclic thioether moiety and aurone analogues bearing cyclic tertiary amine moiety were designed and synthesized under microwave irradiation. The synthetic protocol was found to present many advantages, such as higher yields, shorter reaction time (10-20 min), mild condition, and readily isolation of the products. The synthesized compounds were assayed for their antitumor activity against four kinds of human solid tumor cell lines including HCCLM-7, Hep-2, MDA-MB-435S, and SW-480. Two compounds, (Z)-2-((4-benzyl-piperazin-1-yl)methylene)benzofuran-3(2H)-one 5e and (Z)-2-((4-(bis(4-fluorophenyl)methyl)piperazin-1-yl)methylene)benzofuran-3(2H)-one 5f, were identified as the most promising candidates with the IC(50) values in the range of 4.1-13.1 microM. Further cell cycle studies revealed that compounds 5e and 5f arrest the cell cycle in G(0)/G(1) phase and displayed apoptosis-inducing effect on Hep-2 cells.