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Graphical abstract Highlights • Push-pull benzothiazole derivatives were designed based on firefly oxyluciferin. • The derivatives show solvatochromic fluorescence with high quantum yields. • Solid state fluorescence of the derivatives were depended on the crystal structures. Abstract 6-Dimethylamino-2-phenylbenzothiazoles with a carboxy, ester and amide substituent on the 2-phenyl group were prepared as a series of the push-pull benzothiazoles, and their spectroscopic and photophysical properties in solutions were investigated. The derivatives showed solvatochromic fluorescence with quantum yields over 0.68 in various organic solvents similar to the core fluorophore structure. The color variation ranges in fluorescence solvatochromism of the derivatives were wider than that of the original compound having the core structure, 6-dimethylamino-2-phenylbenzothiazole. It was also found that the derivatives together with the original compound show solid state fluorescence depending on their crystal structures. In particular, an ester derivative with a protected serine has a reasonable crystal packing leading to increase in fluorescence efficiency. The results of the present study provide a guide to design push-pull 2-phenylbenzothiazoles exhibiting fluorescence in solution and the solid state. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Benzothiazole derivatives with tunable emission were synthesized. • The compounds demonstrate improved quantum yields. • The compounds are emissive both in solution and in solid state. • The compounds are bright in live cells with various colors. Abstract The 2-(2-hydroxyphenyl)-benzothiazole (HBT) fluorophore has attracted considerable attention due to its excited-state intramolecular proton transfer (ESIPT) based emission and its large Stokes shift. However, this fluorophore possesses several disadvantages including low quantum yield and short emission in the blue range. In this study, by coupling HBT at the ortho -, meta -, and para -positions to the hydroxyl group with different heterocycles to extend the conjugation system, we have successfully obtained new fluorophores with tunable emissions both in solution and in the solid-state (409–652 nm). Notably, all of the derivatives demonstrated improved quantum yields compared with the parent HBT structure. Moreover, selected compounds have been shown to shine brightly in live cells, indicating promising potential for bioimaging. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Synthesis of benzothiazole having oxadiazole analogs. • In vitro α- glucuronidase activity. • Identification of a new of α- glucuronidase inhibitor. • Structure Activity Relationship established. • Molecular docking. Abstract Diabetes is one of the pre-dominant metabolic disorders all over the world. It is the prime reason of mortality and morbidity due to hyperglycemia which is link with numerus obstacles. Delaying absorption and digestion of carbohydrate has great therapeutic impact for governing postprandial hyperglycemia. Consequently, alpha glucosidase is one of the potential therapeutic approaches that reduce absorption of glucose and delay carbohydrate digestion hence maintaining blood glucose level. In this regard we have synthesized benzothiazole based oxadiazole in search of potent anti-diabetic agent as α-glucosidase Inhibitors. Benzothiazole based oxadiazole derivatives 1 – 23 have been synthesized, characterized by 1HNMR, 13CNMR, and MS and evaluated for α-glucosidase Inhibition. All analogs exhibited a varying degree of α-glucosidase inhibitory activity with IC 50 values ranging in between 0.5 ± 0.01–30.90 ± 0.70 μM when compared with the standard acarbose (IC 50 = 866.30 ± 3.20 μM). Structure activity relationship has been established for all compounds. Molecular docking studies were performed to predict the binding interaction of the compounds with the active site of enzyme. [ABSTRACT FROM AUTHOR]

On the pharmaceutical account of the reported anticancer activity of benzothiazole derivatives, differently substituted benzothiazole derivatives 2a–c to 34a,b, attached at 2‐position to different heterocyclic moieties, were synthesized via different chemical reactions. Thirteen of the newly synthesized compounds were selected by the National Cancer Institute, Bethesda, Maryland, USA, and evaluated for their in vitro antitumor activity against 60 human tumor cell lines in a one‐dose screening panel among which two compounds 4 and 17 showed high activity and were selected for further evaluation in the five‐dose full panel assay, in which compound 4 exerted powerful growth inhibitory activity against all cell lines with GI50 ranging from 0.683 to 4.66 μM/L in addition to excellent lethal activity against most of the cell lines. [ABSTRACT FROM AUTHOR]

Benzothiazole derivatives are highly selective and an antitumor therapeutic in vitro and in vivo, highlighting the compound 2‐ (4′‐aminophenyl) benzothiazole (ABT), which exhibits nanomolar concentration activity in vitro against some human breast cancer cells in humans. In this work, we designed new contrast agents based on the structural modification of ABT by complexing them with manganese in order to obtain paramagnetic complexes for efficient diagnosis of breast cancer. The new agents were evaluated by docking studies that allowed investigating interactions and the mode of connection between the active site of the enzyme and the compounds studied. The theoretical and experimental results both indicate that Compound 57 is a promising contrast agent. The novel 2‐ (4′‐aminophenyl) benzothiazole derivatives (ABT) were evaluated by docking studies, the compound 57 was selected as the most active compound and thus synthesized and characterized by 1 HNMR, 13 CNMR and MS. Tests were performed to evaluate cell viability, demonstrating that said compound have antiproliferative activity on the MCF‐7 lineage. Thus, compound may be useful both in the diagnosis and in the antitumor agent. [ABSTRACT FROM AUTHOR]

Some new 1,3,4‐thiadiazoles derived from azo dyes were synthesized. Two different synthesis methods were used for these compounds: Esters pertaining to the azo dyes were converted into 1,3,4‐thiadiazoles, or benzothiazole ester derivatives were converted to 1,3,4‐thiadiazoles followed by the synthesis of azo dye derivatives. The desired products were successfully obtained using the latter method. The molecular structures of these compounds were characterized using spectroscopic methods such as FTIR, 1H NMR, 13C NMR, and elemental analysis. Furthermore, antimicrobial activity was studied for the synthesized compounds. Compound 3e exhibited antimicrobial activity against three different microorganisms. Compounds 3a, 3b, and 3d had activity against two different microorganisms, while compound 3c showed activity against only one microorganism. [ABSTRACT FROM AUTHOR]

A series of benzothiazole derivatives bearing a 1,3,4-thiadiazole moiety were designed, synthesized and evaluated for their antibacterial, antifungal and antiviral activities. The bioassay results indicated that most of target compounds showed good antiviral activities against tobacco mosaic virus (TMV) and antibacterial activities against Xanthomonas oryzae pv. oryzae (Xoo) and Ralstonia solanacearum (Rs). Especially, the anti-Xoo effect of title compounds 5k (N-(5-methoxybenzo[d]thiazol-2-yl)-2-((5-(2-tolyl)-1,3,4-thiadiazol-2-yl)thio)acetamide) and the anti-Rs effect of title compounds 5a (N-(5-nitrobenzo[d]thiazol-2-yl)-2-((5-(4-(trifluorom ethyl)phenyl)-1,3,4-thiadiazol-2-yl)thio)acetmide) respectively reached 52.4% and 71.6% at 100 µg/mL, which are superior to that of bismerthiazol (32.0% and 52.3%). In addition, the protective and inactivation activities of title compound 5i (N-(5-methoxybenzo [d]thiazol-2-yl)-2-((5-(4-nitrophenyl)-1,3,4-thiadiazol-2-yl)thio)acetamide) against TMV were 79.5% and 88.3%, respectively, which are better than that of ningnanmycin (76.4% and 86.8%). The above research showed that benzothiazole derivatives bearing a 1,3,4-thiadiazole moiety may be used as potential molecular templates in searching for highly-efficient antiviral and antibacterial agents. [ABSTRACT FROM AUTHOR]

Abstract T w o ESIPT benzothiazol derivatives and corresponding europium complexes were synthesized and characterized by the 1HNMR spectrum, Mass spectrum, Elemental analysis, UV–Vis analysis, Molar conductivity, Thermogravimetric analysis and FTIR analysis. The fluorescence intensity of the ligands and complexes are compared, and the fluorescence quantum yields are also calculated by the reference method. The results show that two ligands emit orange fluorescence due to the ESIPT process, but both complexes emit red fluorescence after coordinating with Eu3+. Compared with the ligands, the fluorescence intensity and fluorescence quantum yield of the complexes are enhanced, and the monochromaticity is also improved. Because of the stable tetradentate coordination, the fluorescence intensity of EuL7(NO 3) 3 ·2H 2 O is the strongest, and EuL7(NO 3) 3 ·2H 2 O > EuL6(NO 3) 3 ·2H 2 O > Ligand 6 > Ligand 7, so does the fluorescence quantum yields. The electrochemical properties of the complexes show that the HOMO energy level of EuL7(NO 3) 3 ·2H 2 O is higher than that of EuL6(NO 3) 3 ·2H 2 O, but LUMO energy level is lower than that of EuL6(NO 3) 3 ·2H 2 O. These ligands and complexes have potential applications in the field of life sciences and optical materials. Graphical abstract Image 1 Highlights • Two ESIPT benzothiazol derivatives and their corresponding Eu complexes were synthesized and characterized. • All the ligands emit the orange fluorescence, but complexes emit the characteristic red light of Eu3+. • The relationship between the structure of ligands and the fluorescence intensities of target complexes have been discussed. • The fluorescence and electrochemical properties are compared between the tetradentate and the tridentate coordination complexes. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Novel azo linked substituted benzimidazole, benzoxazole, and benzothiazole were synthesized by diazo coupling and characterized by 1H NMR, elemental analysis, FTIR and UV–vis spectroscopy. The newly synthesized compounds were evaluated for invitro antibacterial activity against Staphylococcus aureus and Escherichia Coli strains by Resazurin microtiter assay method (REMA). The minimum inhibitory concentration (MIC in μg/mL) were used to express the antibacterial activities. The azo linked compounds exhibited good to moderate or high antibacterial activities in vitro. Computational studies were performed to correlate HOMO-LUMO gap with antibacterial activity. The comparative molecular docking studies revealed better insights into binding mechanisms. [ABSTRACT FROM AUTHOR]

The syntheses and structures of five molecular salts of protonated 4,4,7,7-tetramethyl-3a,5,6,7a-tetrahydrobenzothiazol-2-ylamine (C11H19N2S+) with different deprotonated carboxylic acids (4-methylbenzoic acid, 4-bromobenzoic acid, 3,5-dinitrobenzoic acid, fumaric acid and succinic acid) are reported, namely 2-amino-4,4,7,7-tetramethyl-4,5,6,7-tetrahydro-1,3-benzothiazol-3-ium 4-methylbenzoate, C11H19N2S+·C8H7O2 -, (I), 2-amino-4,4,7,7-tetramethyl-4,5,6,7-tetrahydro-1,3-benzothiazol-3-ium 4-bromobenzoate, C11H19N2S+·-C7H4BrO2 -, (II), 2-amino-4,4,7,7-tetramethyl-4,5,6,7-tetrahydro-1,3-benzothiazol-3-ium 3,5-dinitrobenzoate, C11H19N2S+·C7H3N2O6 -, (III), bis(2-amino-4,4,7,7-tetramethyl-4,5,6,7-tetrahydro-1,3-benzothiazol-3-ium) fumarate, 2C11H19N2S+·C4H2O4 2-,(IV), and the 1:1 co-crystal of bis(2-amino-4,4,7,7-tetramethyl-4,5,6,7-tetrahydro-1,3-benzothiazol-3-ium) succinate and 2-amino-4,4,7,7-tetramethyl-4,5,6,7-tetrahydro-1,3-benzothiazol-3-ium hydrogen succinate 4,4,7,7-tetramethyl-3a,5,6,7a-tetrahydrobenzothiazol-2-ylamine, 1.5C11H19N2S+·0.5C4H4O4 2-·0.5C4H5O4 -. 0.5C11H18N2S, (V). In every case, the cation protonation occurs at the N atom of the thiazole ring and the sixmembered ring adopts a half-chair conformation (in some cases, the deviating methylene groups are disordered over two sets of sites). The C--N bond lengths of the nominal -NH+＝C--NH2 fragment of the cation are indistinguishable, indicating a significant contribution of the -NH--C＝N+H2 resonance form to the structure. The packing for (I)-(V) features a robust local R2 ²(8) loop motif in which the cation forms two near-linear N--H...O hydrogen bonds from the N+--H group and syn H atom of the amine group to the carboxylate group of an adjacent anion [(V) shows disorder of one of these bonds over N--H...O and N...H--O contributors but the same R2 2(8) loop results for both disorder components]. The anti H atom of the -NH2 group also forms an N--H...O hydrogen bond, which results in [001] chains in (I) and (II), isolated centrosymmetric tetramers in (III) and [100] chains in (IV) and (V). Hirshfeld fingerprint plots and contact percentages for the different types of contacts of the cations are discussed. [ABSTRACT FROM AUTHOR]

• Schiff Base with methoxy and both methoxy - bromine showed higher antioxidant activity. • All studied compounds are a colorimetric sensor for F−, CN−, AcO−, H 2 PO 4 − and OH− anions under UV lamp and daylight. • Performed fluorescence measurements showed that the compounds ligand and including NO 2 group showed emission signal. • The triplet state of studied compounds ligand and with methoxy and with NO 2 group individually is observed. In this study, a new series of Schiff base benzothiazole derivatives were synthesized and their structures were characterized by elemental analysis, FTIR, UV–VIS and NMR spectroscopy. The biological, sensory and photophysical properties of the benzothiazole derivatives were investigated. The sensing properties of the compounds were investigated UV–VIS spectroscopically, calorimetrically and theoretically. All compounds showed colorimetric, fluorometric and spectroscopic sensor properties for F−, CN−, AcO−, H 2 PO 4 − and OH− anions. Furthermore, DNA binding, DNA cleavage and antioxidant activities of compounds 1 - 4 were investigated. All compounds affected pBR322 DNA both hydrolytically and oxidatively, interacted with DNA in electrostatic mode, and also compounds 1 and 2 exhibited antioxidant activity close to standard BHT. In addition, the effects of electron donating and accepting substituents on the emission properties and charge transfer dynamics were investigated by fluorescence and femtosecond transient absorption spectroscopy measurements, respectively. According to fluorescence measurements, compounds 3 and 4 showed emission signal, while compounds 1 and 2 showed fluorescence quenching and weaker emission signal. [ABSTRACT FROM AUTHOR]

[Display omitted] • A sensitive fluorescence probe TZ-NBD for the recognition of biothiols with dual-channel was constructed. • Dual-channel response improves the probe's anti-interference ability. • TZ-NBD showed fast response, good sensitivity, and near-infrared fluorescence signal. • TZ-NBD was successfully used for high-quality imaging of biothiols in living cancer cells and zebrafish. Biothiols play a crucial role in maintaining redox balance in organisms, and anomalous levels of biothiols in human organs can lead to various sicknesses and biological disorders. This work developed a novel sensitive fluorescent probe TZ-NBD with double channels for highly efficient recognition of biothiols. TZ-NBD adopts 4-Chloro-7-nitrobenzofurazan (NBD-Cl) as the recognition moiety with simultaneous fluorescence output. By incorporating NBD-Cl with the other fluorophore, benzothiazole dihydrocyclopentachromene derivative (TZ-OH), the dual-channel sensitive fluorescence probe TZ-NBD was built. The existence of Cys/ Hcy could significantly trigger both the green and red fluorescent emissions, which were derived from fluorophores amine-substituted NBD and TZ-OH, respectively. While exposing to GSH, only the red-channel fluorescence signal could be detected, indicating the release of TZ-OH. The phenomena was mainly attributed to the fact that sulfur-substituted NBD has nearly no fluorescence, while amine-substituted NBD shows obvious green fluorescence. In our study, TZ-NBD exhibited dual-channel sensitivity, fast response, and excellent selectivity to biothiols in vitro. Moreover, TZ-NBD was favorably utilized for recognition of biothiols in vivo. We believe that the sensitive fluorescence probe with double channels can afford an alternate approach for monitoring biothiols in organisms and would be useful for studying diseases associated with biothiols. [ABSTRACT FROM AUTHOR]

• Synthesis and characterization of unprecedented bioactive benzothiazole mono-azo molecules. • Photophysical probing interactions were studied using various organic solvents. • Computational investigations - Global reactive parameters, FMOs, Molecular electrostatic potential maps. • Antimycobacterial studies of synthesized mono-azo molecules. In the present work, we have presented a very detailed study of unprecedented mono-azo benzothiazole derivatives. The targeted molecules were synthesized by a single-step involving diazotizing the primary aromatic amines followed by resultant diazonium salts coupling with N, N-Diethyl-m-toluidine (DEMT) through electrophilic substitution reaction influenced by positive mesomeric effect (+ M effect) under suitable experimental conditions. The FT-IR, UV–vis, Photoluminescence (PL), 1H NMR, 13C NMR, and HRMS techniques were used to investigate the synthesized mono-azo benzothiazole dye derivatives. Additionally, for the first time, calculations based on density functional theory have been used to examine the ground state geometry, electronic structure, and molecular characteristics potential region maps of four benzothiazole mono-azo architectures (CR1-CR4). The effectiveness of the synthesized dye colourants against M. tuberculosis, H37Rv was assessed by utilizing the agar well diffusion assay method (ATCC 27,294), amongst the studied mono-azo derivatives, CR 3 and CR 4 exhibited a good zone of inhibition compared to CR 1 and CR 2. The compound CR 1 demonstrated sensitivity at 20 µM, compared to 48.2 µM for the reference gentamicin. The antibacterial activity of the CR1 and CR4 compounds was revealed to have a 19 mm zone of inhibition. The derivative CR 1 displayed 42.86 and CR 3 displayed 38.75 of the concentration IC 50 in 100 μl/ml, respectively, based on their cytotoxic potentiality. By using a common coupling component, synthesized unprecedented mono-azo benzothiazole architectures. The structural features of the dye derivatives were confirmed by various analytical techniques. The DFT and MEP are corresponding to high-density energetic structural parameters of mono-azo colourants. Along with the Uv-absorption and emission behaviour, the zone of inhibition regarding antimycobacterial potency was evaluated. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A "double reaction" type-based fluorescent probe (BZT) for the detection of superoxide anion (O 2 •−) in the living cells was developed. • The response mechanism of BZT to O 2 •− was based on double chemical reactions including a nucleophilic reaction and a cyclization reaction. • The probe BZT could show high sensitivity and selectivity to O 2 •−. • By fluorescence imaging of O 2 •−, it was demonstrated that rutin could efficiently scavenge the endogenous O 2 •− induced by rotenone. Superoxide anion (O 2 •−) is an important ROS in living systems, and rapid and in situ detection of O 2 •− is critical for the in-depth study of its roles in the closely related diseases. Herein, we present a "double reaction" type-based fluorescent probe (BZT) for the imaging of O 2 •− in living cells. BZT employed a triflate group as a recognition site for O 2 •−. In response to O 2 •−, the probe BZT underwent double chemical reactions, including the nucleophilic reaction between O 2 •− and triflate, and the cyclization reaction through the other nucleophilic reaction between hydroxyl and cyano group. BZT could show high sensitivity and selectivity to O 2 •−. Biological imaging experiments demonstrated that the probe BZT could be successfully applied to detect the exogenous and endogenous O 2 •− in living cells, and the results suggested that rutin could efficiently scavenge the endogenous O 2 •− induced by rotenone. We expected that the developed probe could provide a valuable tool to investigate the pathological roles of O 2 •− in relevant diseases. [ABSTRACT FROM AUTHOR]

• A green strategy has been applied to synthesize novel benzothiazole compounds benzothiazole. • Antiurease activity revealed a promising results compared with thiourea as the standard urease inhibitor. • Molecular modeling studies highlight the potential of benzothiazole derivatives as inhibitors of urease. Recently, benzothiazole derivatives have garnered significant attention among the research community due to their pharmaceutical and biological significance. Likewise, in this study, novel benzothiazole derivatives were synthesized via a novel green approach and characterized by IR, NMR, and ESI MS spectroscopic methods. The synthesized compounds were evaluated for their urease inhibitory potential. All analogs exhibited varied degrees of urease inhibitory potential with IC 50 values ranging between 6.01±0.23 and 21.07±0.77 μ M, when compared with thiourea as the standard urease inhibitor (IC 50 = 11.58±0.34 μ M). Among the tested derivatives, compound 3b (6.01±0.23 μ M) was identified as the most potent inhibitor of urease. Based on the promising in vitro evaluation, a further in-silico study was carried out in order to understand the structure-activity relationship using DFT calculation. Molecular docking and ADMET prediction were investigated to evaluate the affinity of our synthesized compounds with anti-ureas targets. Then, a molecular dynamic simulation was suggested to confirm the stability of our derivatives in interaction within the active site. [Display omitted] [ABSTRACT FROM AUTHOR]

A series of hydroxy thiophene-conjugated benzothiazole derivatives (HTB s) was prepared to investigate their fluorescence emission behaviors and capability to selectively stain subcellular organelles for fluorescence imaging. The HTB derivatives exhibited excited-state intramolecular proton transfer (ESIPT) and intramolecular charge transfer (ICT) behaviors, according to their molecular structure. Subtle changes in the molecular structure of the HTB influenced its response to changes in the surrounding environment, such as the solvent polarity and/or pH. In vitro cellular imaging experiments revealed that HTB A (5-(benzo[d]thiazol-2-yl)-[2,2′-bithiophen]-4-ol) could selectively stain mitochondria. In contrast, HTB B -CO 2 Et (ethyl 5'-(benzo[d]thiazol-2-yl)-3′-hydroxy-[2,2′-bithiophene]-5-carboxylate), which contains a regioisomeric hydroxy thiophene unit with an electron-withdrawing ethyl ester group, showed the capability to stain lipid droplets (LDs) in living cells. When the hydroxyl group in HTB B -CO 2 Et was protected with a benzyl group, effective staining of LDs in live cells was achieved. Thus, we successfully obtained an effective fluorescent probe. Collectively, the results indicated that small structural changes resulted in substantial changes in the intracellular localization and in vitro imaging ability of the prepared compounds. [Display omitted] • Hydroxy thiophene-conjugated benzothiazole derivatives (HTB s) were synthesized. • HTB s exhibited polarity-dependent bright emission due to ESIPT and ICT. • The structural change of HTB s enabled selective staining of mitochondria and lipid droplets. [ABSTRACT FROM AUTHOR]

• One-pot amidoalkylation of ferrocene. • Crystallographic analysis of 2,2,2-trichloroethyl 2-ferrocenylbenzothiazole-3(2H)-carboxylate. • DDQ as a suitable oxidizer for N -alkoxycarbonyl-2-ferrocenylbenzothiazolines. • New method for the synthesis of 2-ferrocenylbenzothiazole. Novel ferrocenyl-containing benzothiazole derivatives were synthesised in moderate yields (49–66 %) by one-pot α -amidoalkylation of ferrocene. The reaction conditions were critically evaluated and the crystal structure of one of the amidoalkylated ferrocenes was resolved. Oxidation of the obtained compounds led to known fully aromatic 2-ferrocenylbenzothiazole in 81 % yield, which represents a convenient alternative to earlier methods utilizing cyclocondensation reactions. [Display omitted] [ABSTRACT FROM AUTHOR]

The article titled "Carbon Neutralization" discusses the development of photocatalysts based on non-covalent strategies, which have shown promise in medical and organic materials. The focus is on designing and synthesizing effective organic photosensitizers or photocatalysts that can convert substrates into reactive oxygen species (ROS) under light for efficient photocatalytic reactions. The article specifically highlights the design and synthesis of benzothiazole derivatives (MPBT) that can form supramolecular dimers with CB[8] through host-guest interaction. These dimers produce more superoxide anion radicals, which can be used in the oxidative hydroxylation of arylboric acid. The authors of the article are Xin-Long Li, Yue-Bo Wang, Ying Wang, Rong-Zhen Zhang, Rui-Zhi Dong, Hui Liu, ShengSheng Yu, Ning Han, and Ling-Bao Xing. [Extracted from the article]

The burden of antibiotic resistance necessitates a continued search for new antimicrobials. We evaluated the antimicrobial activities of novel benzothiazoles synthesized by our group. Antibacterial activity was evaluated in vitro in Staphylococcus aureus, Bacillus subtilis, and Escherichia coli, while the antifungal activity was tested in Candida albicans and Aspergillus niger, and expressed as the minimum inhibitory concentration (MIC; µg/mL). MIC values of benzothiazole compounds ranged from 25 to 200 µg/mL. Compounds 3 and 4 gave high antibacterial and moderate antifungal activities, while 10 and 12 showed moderate activity against all tested organisms. In addition, some benzothiazole compounds significantly suppressed the activity of Escherichia coli dihydroorotase and inhibited the dimorphic transition of Candida albicans. Moreover, the active benzothiazole compounds induced DNA and protein leakage in Aspergillus niger spores. Molecular interactions of benzothiazole derivatives with dihydroorotase revealed the formation of hydrogen bonds with the active site residues LEU222 or ASN44. Strong hydrophobic interactions of the bulky thiazole and naphthalene rings at the entrance to the active site might interfere with the access of substrates to their binding sites, which results in dihydroorotase inhibition. Thus, inhibition of dihydroorotase might contribute to the observed antimicrobial actions of these compounds.

Neurodegenerative diseases such as Alzheimer's disease (AD) are multifactorial with several different pathologic mechanisms. Therefore, it is assumed that multitargeted-directed ligands (MTDLs) which interact with different biological targets relevant to the diseases, might offer an improved therapeutic alternative than using the traditional "one-target, one-molecule" approach. Herein, we describe new benzothiazole-based derivatives as a privileged scaffold for histamine H 3 receptor ligands (H 3 R). The most affine compound, the 3-(azepan-1-yl)propyloxy-linked benzothiazole derivative 4b, displayed a K i value of 0.012 μM. The multitargeting potential of these H 3 R ligands towards AChE, BuChE and MAO-B enzymes was evaluated to yield compound 3s (pyrrolidin-1-yl-(6-((5-(pyrrolidin-1-yl)pentyl)oxy)benzo[d]thiazol-2-yl)methanone) as the most promising MTDL with a K i value of 0.036 μM at H 3 R and IC 50 values of 6.7 µM, 2.35 µM, and 1.6 µM towards AChE, BuChE, and MAO-B, respectively. These findings suggest that compound 3s can be a lead structure for developing new multi-targeting anti-AD agents.

Abstract The spectroscopic features and molecular structure of 5-fluoro-6-(4-methylpiperazin-1-yl)benzo[ d ]thiazol-2-amine (2-ABT) have been determined. Single-crystal X-ray analysis and vibrational spectroscopy have revealed the existence of 2-ABT in the amino tautomeric form in the solid state. Properties of 2-ABT in solution have been investigated using 1H and 13C NMR spectroscopy along with electronic absorption spectroscopy. The experimental data are complemented by DFT and TD-DFT calculations at the B3LYP/6–311 + g(2d,p) level. TD-DTF-predicted spectroscopic and structural properties for both amino and imino tautomers of 2-ABT are compared with the measured data; no strong evidence for the presence of the imino tautomer is found within the experimental data. Calculated energy differences between the tautomers strongly favour the amino tautomer over the other. Indeed, X-ray crystallography has unequivocally shown the amino tautomer which co-crystallized with one water molecule in the orthorhombic space group Pnna. Analysis of the crystal packing reveals an interesting structural motif which comprises an assemblage of the 2-ABT molecules through π···π stacking interactions. Furthermore, there exist hydrogen-bonding interactions involving the lattice solvent and the amino group along with the benzothiazole nitrogen atom. Graphical abstract Image 1 Highlights • Amino (C NH 2)–imino (–C N H) tautomerism. • Spectroscopy and X-ray structure determination. • Density functional and time-dependent DFT calculations. [ABSTRACT FROM AUTHOR]

Graphical abstract A new functionalized mesoporous catalyst (Cu(II)-Glycerol/MCM-41) has been synthesized as a highly efficient heterogeneous nanocatalyst for the synthesis of Benzothiazols derivatives. Abstract A new functionalized mesoporous catalyst (Cu(II)-Glycerol/MCM-41) has been synthesized as a highly efficient heterogeneous nanocatalyst for the synthesis of benzothiazoles derivatives. Powder XRD, TGA, TEM, SEM, EDX, BET, FT-IR and ICP-OES techniques are employed to characterize the prepared nanocatalyst. These one-pot reactions were carried out under green and mild reaction conditions in EtOH as a green solvent and the catalyst can be reused up to 5 consecutive cycles without significant change in its catalytic activity. [ABSTRACT FROM AUTHOR]

In recent years heterocyclic compounds analogues and derivatives have attracted wide attention due to their useful biological and pharmacological properties. Indole, Benzothiazole and its analogs are versatile substrates, which can be used for the synthesis of numerous heterocyclic compounds. Indole, Benzothiazole and its derivatives are used in organic synthesis and they are used in evaluating new product that possesses different biological activities. Hence, their extensive structural modification has result in different analogues of Indole and Benzothiazole derivatives depicting wide range of biological and pharmacological activities such as antiviral, anticonvulsant, anti-inflammatory, analgesic, antimicrobial and anticancer. This review article literature survey summarizes the synthesis and pharmacological activities of Indole, Benzothiazole and its derivatives. [ABSTRACT FROM AUTHOR]

We report herein the synthesis of ¾ substituted benzene sulfonamides linked via phenyl ring to a benzothiazole moiety. The title compounds in the two series namely N-(4-(benzothiazole-2-yl) phenyl) 4-substituted benzene sulfonamides and N-(4-(benzothiazole-2-yl) phenyl) 3-substituted benzene sulfonamides were synthesized by condensing 2-(3/4-aminophenyl) benzothiazole with various substituted sulfonyl chlorides. The synthesized compounds were subjected to neurotoxicity screening, computational studies, and evaluation of their anticonvulsant potential. Amongst all the synthesized compounds, compound 9 emerged as the most potent anticonvulsant agent in maximal electroshock (MES) model (standard: phenytoin) in mice and showed three hydrogen bond interactions with the nicotinic acetylcholine ion gated receptors (PDB ID: 2BG9). Interestingly, compound 13 showed five hydrogen bond interactions with the target protein and thus excellent binding affinity upon computational analysis but was found to be neurotoxic. [ABSTRACT FROM AUTHOR]

A new and efficient protocol was developed for synthesis of benzothiazoles as a potential antimicrobial and antioxidant agent using γ-Valerolactone (GVL) as catalyst and solvent under environmentally friendly conditions. The developed synthetic protocol represents a very simple and a novel route for the synthesis of 2- substituted benzothiazole derivatives. In addition, an ultrasound irradiation technique was successfully implemented for performing the reactions in shorter reaction times. The synthesized benzothiazoles were evaluated for antimicrobial and antioxidant activity and was analysed for ADME properties. [ABSTRACT FROM AUTHOR]

Benzothiazole Derivative is one of the important classes of fused cycles -compounds due to these moieties can use as a subunit in great numbers of drug design. For this, the present work focused on preparation six compounds with some derivatives and esterification steps for some of them, then, the investigation of derivatives carried out via many technical like (FT.IR, H.NMR, Some of them by Mass spectra)- spectrophotometric, then inhibition test of derivatives on bacteria. [ABSTRACT FROM AUTHOR]

Twelve new derivatives of benzothiazole bearing benzenesulphonamide and carboxamide were synthesised and investigated for their in vivo anti-inflammatory, analgesic and ulcerogenic activities. Molecular docking showed an excellent binding interaction of the synthesised compounds with the receptors, with 17c showing the highest binding energy (-12.50 kcal/mol). Compounds 17c and 17i inhibited carrageenan-induced rat paw oedema at 72, 76, and 80% and 64, 73, and 78% at 1 h, 2 h, and 3 h, respectively. In the analgesic activity experiment, compounds 17c, 17 g, and 17i had ED50 (µM/kg) of 96, 127, and 84 after 0.5 h; 102, 134, and 72 after 1 h and 89, 156, and 69 µM/kg after 2 h, respectively, which were comparable with 156, 72, and 70 µM/kg for celecoxib. The ulcerogenic index of the most active derivatives 17c and 17i were 0.82 and 0.89, respectively, comparable to 0.92 for celecoxib. The physicochemical studies of the new derivatives showed that they will not have oral bioavailability problems. [ABSTRACT FROM AUTHOR]

In recent times, hot-dip galvanized steel (HDGS) products have been utilized in several engineering construction projects including architecture and structural fabrication due to their excellent durability and appearance. The galvanized Zn layer on steel is designed as a sacrificial anode against corrosion but it eventually fails due to biofouling and chloride-induced degradation. This work is designed to study the extent of damage caused by sulphate–reducing bacterial (SRB) colonization of HDGS surfaces, monitored within defined duration. The biocorrosion mechanism of the metal surface is elucidated by means of electrochemical assessments of associated liquid/metal interfacial phenomena evolved within the bacterial culture period and by monitoring the extent of surface pitting caused by associated biological activities of absorbed SRB cells. The rate of biocorrosion accompanying bacterial metabolic activities for test and control systems are further quantified by weight loss technique in the presence of a benzothiazole biocidal (MBT) additive capable of inhibiting biofilm growth at anaerobic conditions. MBT doped within the SRB-inoculated culture medium inhibited both SRB cellular growth and HDGS pitting, by forming passive antibiotic films on the metal surface. Since sustainable development is an important aspect of modern material designs and construction economics, this work provides a biofilm engineering background to safe monitoring of HDGS products. [ABSTRACT FROM AUTHOR]

In the present investigation, we employ a dual approach consisting of experimental and computational techniques to synthesise and characterise the Schiff-base including the moieties of nitrophenyl (3), nitrothiazole (5) and nitrobenzothiazole (7). The synthesised Schiff bases are confirmed by FT-IR, 1H-NMR and UV-visible spectroscopic techniques. The experimental UV-visible spectroscopic results are compared to the theoretically calculated TD-DFT results. There is a reasonably good agreement between the experimental and the theoretically calculated spectroscopic results. We also calculate the third-order nonlinear optical (NLO) polarizability (γ) of above entitled derivatives using finite field (FF) approach and DFT methods. The compound 7 shows an amplitude of γ as large as 124.15×104 a. u., which is found to be several times larger than that of para-nitroaniline. Moreover, the partial and total density of states (PDOS and TDOS) along with electrostatic potential maps are calculated to get more physical insights into the structure-property relationship and electronic communications between terminal donor and central core acceptor moieties in the synthesised compounds. The present investigation highlights the significance of indigenously synthesised nitrothiazole and nitrobenzothiazole compounds as efficient NLO materials, which may evoke the interest of scientific community in such efficient NLO materials for their potential utilization in device applications. [ABSTRACT FROM AUTHOR]

Synthetic delivery systems have great potential for overcoming problems associated with systemic toxicity that accompanies chemotherapy with the use of cisplatin and family of platinum anticancer drugs. Mesoporous silicates have been studied in context of drug delivery and drug targeting. In this paper we report the studies of loading and release of a platinum complex, [Pt(DTBTA)(DMSO)Cl]Cl∙CHCl 3 (1) where DTBTA = 2,2′-dithiobis(benzothiazole), that was recently synthesized and structurally characterized. Evaluation in vitro of antitumor activity against a human breast cancer cell line (MCF-7) showed a very potent activity of complex( 1 ). Therefore, we thought to incorporate this compound into MCM41 mesoporous silica and into analogous support functionalized with amino groups (MCM41-NH 2 ). The complex( 1 ) encapsulation efficiency % (EE%) in MCM41 and in MCM41-NH 2 , respectively, was evaluated by using UV–Vis spectroscopy. The porosimetry and IR spectra confirmed that the drug was within the pores in MCM-41 and that the complex( 1 ) binds MCM41-NH 2 with the aminopropyl functional groups of the mesoporous channels, respectively. The study of release was performed by using UV–Vis spectroscopy at 37 ± 1 °C in 0.1 M phosphate buffer solution (PBS) having pH 7.4 to simulate the physiological pH of blood. In order to investigate the efficacy of MCM-41/complex( 1 ) and MCM41-NH 2 /complex( 1 ) conjugates, we have measured their ability to kill cancer cells of MCF-7 (human breast cancer). MTT test and cytofluorimetric assay of exposure of phosphatidylserine to the outer membrane were carried out to measure cytotoxicity and apoptosis induced by MCM41/complex( 1 ) and MCM41-NH 2 /complex( 1 ). The investigated systems were very efficient for pharmaceutical controlled release and a promising agent for combination therapies. [ABSTRACT FROM AUTHOR]

The use of a recyclable heterogeneous nanomagnetic solid acid catalyst, [Fe3O4@SiO2@(CH2)3NPC-SO3H]Cl, in a simple and highly efficient synthesis of benzothiazole derivatives by the reaction of aldehydes and o-aminothiophenol in water is reported. The MNP catalyst was characterized by FT-IR spectra, SEM, and TGA analysis, and vibrating sample magnetometery (VSM). The catalyst can be separated and recycled repeatedly by an external magnet without a significant loss in yield. [ABSTRACT FROM AUTHOR]

In this work, hydrogen-bonded liquid crystal exhibiting phase dependent fluorescence has been reported. The H-bonded materials were prepared using pyridenyl benzothiazole and alkoxy benzoic acid as H-bond acceptor and donor respectively. The formation of the target materials was confirmed via different spectroscopic technique and their mesogenic behaviour has been studied through polarising optical microscope, differential scanning calorimetry and 2D-X-ray diffraction. The H-bonded mesogenic material showed aggregation dependent fluorescence switching when subjected to transformation from isotropic-nematic-crystalline phase sequence. Computational studies were performed to probe into fluorescence switching behaviour of the mesogenic material. [ABSTRACT FROM AUTHOR]

17β-Hydroxysteroid dehydrogenase type 10 (17β-HSD10) is a steroidogenesis enzyme known for its potential role in Alzheimer's disease. For comparison purposes between steroidal and nonsteroidal 17β-HSD10 inhibitors 1 and 2, respectively, we attempted the chemical synthesis of benzothiazole phosphonate derivative 2. Instead of a one-pot synthesis, we report a two-step synthesis with characterization of both imine intermediate 5 and final compound 2. Furthermore, complete assignation of ¹H and 13C nuclear magnetic resonance (NMR) signals of 2 is provided, as we observed a divergence of NMR data with those published previously. Finally, biological assays showed that 1 and 2 inhibited the oxidation of estradiol (E2) into estrone (E1) by the 17β-HSD10 recombinant protein. However, in human embryonic kidney (HEK)-293 intact cells transfected with 17β-HSD10, only the steroidal inhibitor 1 induced a dose-dependent inhibition of E2 to E1 transformation. [ABSTRACT FROM AUTHOR]

Two proton transfer compounds, formed between 2-aminobenzothiazole derivatives (2-aminobenzothiazole (abt) and 2-amino-6-ethoxybenzothiazole (EtOabt)) and 5-sulfosalicylic acid dihydrate (H3ssa) as parent compounds, (Habt)+(H2ssa)− (1) and (HEtOabt)+(H2ssa)− (2) and their Cu(II) complexes (3 and 4, respectively) have been prepared and characterized using spectroscopic techniques. The single crystal X-ray diffraction method has been also applied to 3 and 4. Although 3 has a distorted octahedral form, 4 exhibits a distorted square pyramidal geometry. All compounds, including saline and diclofenac sodium as standards, have been evaluated pharmacologically for their anti-inflammatory and analgesic activities in rats and mice. Parent compounds (abt, EtOabt, and H3ssa) 3 and 4 show significant anti-inflammatory and analgesic activities as compared with control compounds. [ABSTRACT FROM AUTHOR]

A series of new azoalkyl ether imidazo[2,1- b ]benzothiazoles were developed via a convenient synthetic procedure. The antimicrobial assays showed that a good number of the prepared derivatives exhibited significant inhibitory properties against most of the tested strains. Especially 2-methyl-5-nitroimidazole derivative 5a presented superior inhibit activity against MRSA and B. typhi with MIC = 4 μg/mL and MIC = 1 μg/mL, respectively. The highly active compound 5a showed low toxicity against mammalian cells without obvious triggering of the development of bacterial resistance, and it also possessed rapid bactericidal efficacy. Molecular docking study exposed that the active molecule 5a could interact with the active site of S. aureus gyrase through hydrogen bond. Quantum chemical studies were also performed to explain the high antibacterial activity. Further investigation revealed that compound 5a could significantly associate with gyrase–DNA complex by mean of hydrogen bonds and could efficiently intercalate into MRSA DNA to form 5a –DNA supramolecular complex, which impart potent bioactivity. [ABSTRACT FROM AUTHOR]

Malignant melanoma is an important type of cancer worldwide due to its aggressiveness and poor survival rate. Significant efforts to understand the biology of melanoma and approaches to treat the advanced disease are focused on targeted gene inhibitors. Frequently mutated genes, such as NRAS, B-RAF and TP53, significantly exceed the frequency of mutations of other genes, emphasizing their importance for future targeted therapies. Considering the antitumor activity of benzothiazolic derivatives, this study aimed to demonstrate the action of benzothiazolic ( E )-2-((2-(benzo[ d ]thiazol-2-yl)hydrazono)methyl)-4-nitrophenol (AFN01) against three established human melanoma cell lines that recapitulate the molecular landscape of the disease in terms of its genetic alterations and mutations, such as the TP53 , NRAS and B-RAF genes. The results presented here indicate that AFN01, as a significant cytostatic and cytotoxic drug due to its induction of DNA fragmentation, causes single and double DNA strand breaks, consequently inhibiting cell proliferation, migration and invasion by promoting apoptosis. Our data suggest that AFN01 might be considered as a future therapeutic option for managing melanoma. [ABSTRACT FROM AUTHOR]

A simple structured reaction-based probe for peroxynitrite (ONOO − ) was developed by using benzothiazole hydrazone base of the excited-state intramolecular proton transfer (ESIPT) dye. It was constructed from 2-hydrazinylpyridine and 3-(benzo[d]thiazol-2-yl)-2-hydroxy-5-methylbenzaldehyde which possesses itself weak fluorescence and displayed prominent fluorescence response towards ONOO − by oxidizes the C=N bond to an aldehyde in aqueous solution. The probe exhibited excellent selectivity and high sensivity towards ONOO − with a low dectection limit of 5.8 × 10 −8  M in physiological condition. Moreover, the probe could realize fast recognition to ONOO − in as short as 60 s. In addition, the probe was also successfully used for living cell imaging. [ABSTRACT FROM AUTHOR]

In the present work, Schiff base ligands (1-4) were prepared by condensation of 2-amino-6-substituted-benzothiazole and salicyaldehyde in a 1:1 molar ratio and were further treated with diorganotindichloride R’2SnCl2 leading to a series of organotin(IV) complexes (5-20) of type R’2SnL1−4Cl [R’ = Ph, Bu, Et, Me]. The prepared Schiff base ligands and the organotin(IV) complexes were characterized by various spectroscopic techniques (1H, 13C, 119Sn NMR, FT-IR) and physical techniques. All the synthesized compounds were evaluated for in vitro antibacterial and antifungal activity against two Gram positive bacterial strains B. cereus, S. aureus, two Gram negative bacterial strains E. coli, P. aeruginosa and two fungal strains A. niger and A. flavus by serial dilution method. The spectral data revealed that the complexes were pentacoordinated with bidentate ligands coordinated through oxygen and nitrogen. The results of antimicrobial activity revealed that the synthesized complexes were more toxic towards Gram positive bacterial strains as compared to Gram negative bacterial strains. From the results of QSAR analysis, it was indicated that the antimicrobial activity of the synthesized compounds were controlled by topological parameters (molecular connectivity indices). [ABSTRACT FROM AUTHOR]

It was found that film composites of the copolymer of styrene with octyl methacrylate with additions of the monomers of pyrido[2,1-b]benzothiazole derivatives have hole-type photoconductivity while the internal photoelectric effect in this medium is determined by the photogeneration of charge carriers from the monomers and transfer of nonequilibrium charge carriers through these monomers. In transition to a monomer with a more efficient conjugation system the photoconductivity and photovoltaic response are increased. [ABSTRACT FROM AUTHOR]

Abstract: In this work, using density functional theory and time‐dependent density functional theory methods, we theoretically studied the excited‐state behaviors of 3 novel 2‐(2‐hydroxyphenyl)benzothiazole (HBT) derivatives (HBT‐H‐H, HBT‐CN‐H, and HBT‐CN‐CN). Analyses about primary chemical structures such as bond lengths and bond angles, we found that all the intramolecular hydrogen bonds in these 3 structures should be strengthened in the S1 state upon the photoexcitation. Exploring the infrared vibrational spectra at the hydrogen bonds groups, we confirmed that nonsubstitutional HBT‐H‐H structure might play more important roles in the excited‐state intramolecular proton transfer (ESIPT) reaction than HBT‐CN‐H and HBT‐CN‐CN. Further, investigating vertical excitation process, it can be revealed that charge redistribution involved in hydrogen bonding moieties could facilitate the ESIPT reaction. Based on constructing potential energy curves of both S0 and S1 states, we confirmed that the substituents on HBT systems can reasonably regulate and control the ESIPT processes because of the different potential energy barriers. We deem that this present work not only elaborates the different excited‐state behaviors of HBT‐H‐H, HBT‐CN‐H, and HBT‐CN‐CN but also may play important roles in designing and developing new materials and applications involved in HBT systems in future. [ABSTRACT FROM AUTHOR]

Many cancers have the tumor suppressor p53 inactivated by mutation, making reactivation of mutant p53 with small molecules a promising strategy for the development of novel anticancer therapeutics. The oncogenic p53 mutation Y220C, which accounts for approximately 100,000 cancer cases per year, creates an extended surface crevice in the DNA-binding domain, which destabilizes p53 and causes denaturation and aggregation. Here, we describe the structure-guided design of a novel class of small-molecule Y220C stabilizers and the challenging synthetic routes developed in the process. The synthesized chemical probe MB710 , an aminobenzothiazole derivative, binds tightly to the Y220C pocket and stabilizes p53-Y220C in vitro . MB725 , an ethylamide analogue of MB710 , induced selective viability reduction in several p53-Y220C cancer cell lines while being well tolerated in control cell lines. Reduction of viability correlated with increased and selective transcription of p53 target genes such as BTG2 , p21 , PUMA , FAS , TNF , and TNFRSF10B, which promote apoptosis and cell cycle arrest, suggesting compound-mediated transcriptional activation of the Y220C mutant. Our data provide a framework for the development of a class of potent, non-toxic compounds for reactivating the Y220C mutant in anticancer therapy. [ABSTRACT FROM AUTHOR]

Two-photon absorption (TPA) cross sections of conjugated donor-π-acceptor dipolar structures containing benzothiazole or benzobisthiazolium moieties are determined in a broad spectral range from 700 nm to 1000 nm using two-photon induced fluorescence technique. The TPA cross section values range from 150 GM to 4600 GM. The largest values are observed in near-infrared region. The dipolar derivative of benzothiazole has the largest TPA cross section of 4600 GM at wavelength of 890 nm. A combination of the large TPA in the near-infrared region and the high emission quantum yield makes these compounds excellent candidates for two-photon fluorescence microscopy. [ABSTRACT FROM AUTHOR]

Substituted benzothiazoles play an important role in medicinal chemistry due to their pharmacological properties. Their 2-substituted derivatives are often prepared from 2-chlorobenzothiazoles, which in turn can be synthesized from the 2-mercapto precursor using sulfuryl chloride. In practice, this seemingly straightforward and widely used reaction can be impeded by poor reproducibility and low reaction yields. In this communication, we report that the simple addition of water to the reaction leads to remarkable improvements in reaction efficiency. We attribute this effect to the formation of acid through partial hydrolysis of sulfuryl chloride. This hypothesis is supported by the observation that improved yields were also obtained in the presence of some anhydrous acidic additives. The simple combination of sulfuryl chloride and water reproducibly provides excellent yields for a range of chlorinated products. [ABSTRACT FROM AUTHOR]

Mercapto benzothiazole linked 1,2,4-oxadiazole derivatives were designed ( 4a-u ) as new anti-inflammatory agents using bioisosteric approach and docking studies. The docking results clearly indicated that the compounds 4a-u shown good docking interaction towards COX-2 enzyme. In silico drug-like properties were also calculated for compounds ( 4a-u ) and exhibited significant H-bond acceptor ratio. All compounds were synthesized and biologically evaluated using in vitro COX-1, COX-2 and 5-LOX assays. Compound 4k and 4q (IC 50  = 6.8 μM and IC 50  = 5.0 μM) found to be potent, selective COX-2 inhibitors and display better anti-inflammatory activity than standard Ibuprofen. Compound 4l and 4e found to be potent inhibitors against 5-LOX (IC 50  = 5.1 μM and IC 50  = 5.5 μM). The in vivo anti-inflammatory activity studies shown that the compounds 4q and 4k effectively reducing the paw edema volume at 3h and 5h than standard drug Ibuprofen. The DPPH radical scavenging activity provided anti-oxidant activity of compound 4e (IC 50  = 25.6 μM) than reference standard Ascorbic acid. [ABSTRACT FROM AUTHOR]

In this paper novel isoindolines substituted with cyano and amidino benzimidazoles and benzothiazoles were synthesized as new potential anti-cancer agents. The new structures were evaluated for antiproliferative activity, cell cycle changes, cell death, as well as DNA binding and topoisomerase inhibition properties on selected compounds. Results showed that all tested compounds exerted antitumor activity, especially amidinobenzothiazole and amidinobenzimidazole substituted isoindolin-1-ones and benzimidazole substituted 1-iminoisoindoline that showed antiproliferative effect in the submicromolar range. Moreover, the DNA-binding properties of selected compounds were evaluated by biophysical and biochemical approaches including thermal denaturation studies, circular dichroism spectra analyses and topoisomerase I/II inhibition assays and results identified some of them as strong DNA ligands, harboring or not additional topoisomerase II inhibition and able to locate in the nucleus as determined by fluorescence microscopy. In conclusion, we evidenced novel cyano- and amidino-substituted isoindolines coupled with benzimidazoles and benzothiazoles as topoisomerase inhibitors and/or DNA binding compounds with potent antitumor activities. [ABSTRACT FROM AUTHOR]