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

The how and why of naphthalimide/heterocycle-fused hybrid dyes: an overview of the latest developments in the quest for dyes with innovative optical properties

In this review, a variety of hybrid structures fusing aromatic heterocycles of different natures to a naphthalimide backbone are discussed. This strategy constitutes an efficient approach to generate original structures displaying singular photophysical properties and thus offering new perspectives in the fields of fluorogenic detection, optoelectronics, and photodynamic therapy. In this review, different synthetic approaches and structures reported in the literature are discussed. A critical look at the design and the applications of these new fused hybrids allows us to evaluate the benefits and drawbacks of a fused hybrid strategy applied to naphthalimides.

Ionic Reactivity of 2-Isocyanoaryl Thioethers: Access to 2-Halo and 2-Aminobenzothia/Selenazoles

An ionic cascade insertion/cyclization reaction of thia-/selena-functionalized arylisocyanides has been successfully developed for the efficient and practical synthesis of 2-halobenzothiazole/benzoselenazole derivatives. This synthetic protocol, incorporating a halogen atom when forming the five-membered ring of benzothia/selenazoles, is different from the existing ones, where halogenation of the preformed benzothia/selenazole precursors happens. Additionally, a facile access to 2-aminobenzothiazoles is also achieved by the one-pot cascade reaction of 2-isocyanoaryl thioethers, iodine, and amines.

Design, Synthesis and Pharmacological Evalution of 1,3,4-Oxadiazole Derivatives as Collapsin Response Mediator Protein 1 (CRMP 1) Inhibitors

OBJECTIVE

The series of 2-(4-Phenylamino)-N-(5-((4-nitrophenoxy)methyl) -1,3,4-oxadiazol- 2-yl)aceta-mide (5a-5e) and substituted N-(5-(Phenoxymethyl)-1,3,4-oxadiazol-2-yl)-2- (phenylamino)acetamide (5f-5i) was designed, synthesized and investigated for Collapsin Response Mediator Protein 1 (CRMP 1) inhibitors as small lung cancer.

DESIGN

Design of compounds was determined by literature review and molecular docking studies in iGEMDOCK 2.0.

MATERIALS AND METHODS

Novel 1, 3, 4 Oxadiazole derivatives were synthesized and characterized by melting point, TLC, IR Spectroscopy, Mass spectroscopy and 1H NMR. In vitro biological evaluation was performed on NCI-H2066 cell line for different concentrations 10-1000μM by telomeric repeat amplification protocol assay. The assay of telomerase in cellular extracts was modified from the PCR-based Telomeric-Repeat Amplification Protocol (TRAP), using the oligonucleotides TS and CX.

RESULTS

Novel substituted 2-(4-Phenylamino)-N-(5-((4-nitrophenoxy)methyl)-1,3,4-oxadiazol-2- yl) acetamide (5a-5e) and substituted N-(5-(Phenoxymethyl)-1,3,4-oxadiazol-2-yl)-2-(phenylamino) acetamide (5f-5i) were synthesized, and characterized using spectral and analytical data. All compounds have shown considerable % inhibition of Cell Growth with respect to Bevacizumab, but compound 5a and 5f were equipotent with respect to activity as compared to standard Bevacizumab.

CONCLUSION

Amongst the hybrids, p-nitro substituted derivative (5a) and p-chloro substituted (5f) showed the highest activity against human lung cancer cell line NCI-H2066 by TRAP assay.

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.

Development and therapeutic potential of 2-aminothiazole derivatives in anticancer drug discovery

Currently, the development of anticancer drug resistance is significantly restricted the clinical efficacy of the most commonly prescribed anticancer drug. Malignant disease is widely prevalent and considered to be the major challenges of this century, which concerns the medical community all over the world. Consequently, investigating small molecule antitumor agents, which could decrease drug resistance and reduce unpleasant side effect is more desirable. 2-aminothiazole scaffold has emerged as a promising scaffold in medicinal chemistry and drug discovery research. This nucleus is a fundamental part of some clinically applied anticancer drugs such as dasatinib and alpelisib. Literature survey documented that different 2-aminothiazole analogs exhibited their potent and selective nanomolar inhibitory activity against a wide range of human cancerous cell lines such as breast, leukemia, lung, colon, CNS, melanoma, ovarian, renal, and prostate. In this paper, we have reviewed the progresses and structural modification of 2-aminothiazole to pursuit potent anticancers and also highlighted in vitro activities and in silico studies. The information will useful for future innovation. Representatives of 2-aminothiazole-containing compounds classification.

l,8-Naphthalimide based DNA intercalators and anticancer agents. A systematic review from 2007 to 2017

In this review, we describe a detailed investigation about the structural variations and relative activity of 1,8-naphthalimide based intercalators and anticancer agents. The 1,8-naphthalimides binds to the DNA via intercalation, and exert their antitumor activities through Topoisomerase I/II inhibition, photoinduced DNA damage or related mechanism. Here, our discussion focused on works published over the last ten years (2007-2017) related to therapeutic applications, in the order of cancer treatment followed by other properties of 1,8-naphthalimides. In preparing for this review, we considered that several seminal reviews have appeared over the last fifteen years and focused on closely related subjects, however, none of them is exhaustive.

A novel bacteriochlorin-styrylnaphthalimide conjugate for simultaneous photodynamic therapy and fluorescence imaging

Propargyl-15²,17³-dimethoxy-13¹-amide of bacteriochlorin e (BChl) and a 4-(4-N,N-dimethylaminostyryl)-N-alkyl-1,8-naphthalimide bearing azide group in the N-alkyl fragment were conjugated by the copper(i)-catalyzed 1,3-dipolar cycloaddition to produce a novel dyad compound BChl-NI for anticancer photodynamic therapy (PDT) combining the modalities of a photosensitizer (PS) and a fluorescence imaging agent. A precise photophysical investigation of the conjugate in solution using steady-state and time-resolved optical spectroscopy revealed that the presence of the naphthalimide (NI) fragment does not decrease the photosensitizing ability of the bacteriochlorin (BChl) core as compared with BChl; however, the fluorescence of naphthalimide is completely quenched due to resonance energy transfer (RET) to BChl. It has been shown that the BChl-NI conjugate penetrates into human lung adenocarcinoma A549 cells, and accumulates in the cytoplasm where it has a mixed granular-diffuse distribution. Both NI and BChl fluorescence in vitro provides registration of bright images showing perfectly intracellular distribution of BChl-NI. The ability of NI to emit light upon excitation in imaging experiments has been found to be due to hampering of RET as a result of photodestruction of the energy acceptor BChl unit. Phototoxicity studies have shown that the BChl-NI conjugate is not toxic for A549 cells at tested concentrations (<8 μM) without light-induced activation. At the same time, the concentration-dependent killing of cells is observed upon the excitation of the bacteriochlorin moiety with red light that occurs due to reactive oxygen species formation. The presented data demonstrate that the BChl-NI conjugate is a promissing dual function agent for cancer diagnostics and therapy.

Synthesis of Oxadiazolyl, Pyrazolyl and Thiazolyl Derivatives of Thiophene-2-Carboxamide as Antimicrobial and Anti-HCV Agents

Introduction:

Three series of pyrazole, thiazole and 1,3,4-oxadiazole, derivatives were synthesized starting from 5-amino-4-(hydrazinocarbonyl)-3-methylthiophene-2-carboxamide (2).

Methods:

All compounds were investigated for their preliminary antimicrobial activity. They were proved to exhibit remarkable antimicrobial activity against Pseudomonas aeruginosa with insignificant activity towards Gram positive bacterial strains and fungi.

Results:

In-vitro testing of the new compounds on hepatitis-C virus (HCV) replication in hepatocellular carcinoma cell line HepG2 infected with the virus utilizing the reverse transcription polymerase chain reaction technique (RT-PCR) generally showed inhibition of the replication of HCV RNA (–) strands at low concentration, while, eight compounds; 3a, 6, 7a, 7b, 9a, 9b, 10a and 11b proved to inhibit the replication of HCV RNA (+) and (–) strands at very low concentration range 0.08-0.36 μg/mL.

Conclusion:

Compounds 7b and 11b displayed the highest anti-HCV and antimicrobial activities in this study.

Design, Synthesis and Evaluation of Naphthalimide Derivatives as Potential Anticancer Agents for Hepatocellular Carcinoma

Two kinds of naphthalimide derivatives were synthesized and evaluated for in vitro their anti-hepatocellular carcinoma properties. Compound 3a with a fused thiazole fragment to naphthalimide skeleton inhibited cell migration of SMMC-7721 and HepG2, and further in vivo trials with two animal models confirmed that compound 3a moderately inhibited primary H22 tumor growth (52.6%) and potently interrupted lung metastasis (75.7%) without obvious systemic toxicity at the therapeutic dose. Mechanistic research revealed that compound 3a inhibited cancerous liver cell growth mostly by inducing G2/M phase arrest. Western blotting experiments corroborated that 3a could up-regulate the cell cycle related protein expression of cyclin B1, CDK1 and p21, and inhibit cell migration by elevating the E-cadherin and attenuating integrin α6 expression. Our study showed that compound 3a is a valuable lead compound worthy of further investigation.

Controlling photophysics of styrylnaphthalimides through TICT, fluorescence and E,Z-photoisomerization interplay

The steady-state and time-resolved spectral properties of styrylnaphthalimides are studied in various solvents.

New role of aminothiazonaphthalimide derivatives: outstanding photoinitiators for cationic and radical photopolymerizations under visible LEDs

Aminothiazonaphthalimide derivatives can act as photoinitiators (when combined with additives) to start the cationic polymerization or the radical polymerization upon exposure to visible LEDs or a polychromatic visible light.

A new Schiff base based on vanillin and naphthalimide as a fluorescent probe for Ag+ in aqueous solution

A new Schiff base based on vanillin and naphthalimide was designed and synthesized as fluorescent probe. The probe showed high selectivity for Ag(+) over other metal ions such as Pb(2+), Na(+), K(+), Cd(2+), Ba(2+), Cr(3+), Zn(2+), Cu(2+), Ni(2+), Ca(2+), Al(3+) and Mg(2+) in aqueous solution. A new fluorescence emission was observed at 682 nm in the presence of Ag(+) ion. The fluorescence intensity quenched with increasing the concentration of Ag(+) at 682 nm. The method of job's plot confirmed the 1:2 complex between Ag(+) and probe, and the mechanism was proposed.

B1-induced caspase-independent apoptosis in MCF-7 cells is mediated by down-regulation of Bcl-2 via p53 binding to P2 promoter TATA box

The Bcl-2 family contains a panel of proteins which are conserved regulators of apoptosis in mammalian cells, like the anti-apoptotic protein Bcl-2. According to its significant role in altering susceptibility to apoptosis, the deciphering of the mechanism of Bcl-2 expression modulation may be crucial for identifying therapeutics strategies for cancer. Treatment with naphthalimide-based DNA intercalators, including M2-A and R16, generally leads to a decrease in Bcl-2 intracellular amounts. Whereas the interest for these chemotherapeutics is accompanied by advances in the fundamental understanding of their anticancer properties, the molecular mechanism underlying changes in Bcl-2 expression remains poorly understood. We report here that p53 contributes to Bcl-2 down-regulation induced by B1, a novel naphthalimide-based DNA intercalating agent. Indeed, the decrease in Bcl-2 protein levels observed during B1-induced apoptosis was correlated to the decrease in mRNA levels, as a result of the inhibition of Bcl-2 transcription and promoter activity. In this context, we evaluated p53 contribution in the Bcl-2 transcriptional down-regulation. We found a significant increase of p53 binding to P(2) promoter TATA box in MCF7 cells by chromatin immunoprecipitation. These data suggest that B1-induced caspase-independent apoptosis in MCF-7 cells is associated with the activation of p53 and the down-regulation of Bcl-2. Our study strengthens the links between p53 and Bcl-2 at a transcriptional level, upon naphthalimide-based DNA intercalator treatment.

6-Methyl-pyridine-2(1H)-thione

There are two unique mol-ecules in the asymmetric unit of the title pyridine-thione derivative, C(6)H(7)NS, each of which adopts the thione rather than the mercaptan form. The rings in both mol-ecules are essentially planar, with maximum deviations from the least-squares planes through all non-H atoms of 0.021 (2) and 0.017 (2) Å. In the crystal structure, the mol-ecules form centrosymmetric cyclic dimers through inter-molecular N-H⋯S hydrogen bonds. Additional C-H(meth-yl)⋯S inter-actions generate a three-dimensional network.