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The nucleophilic substitution reactions of mono- and bis-spiro-2,2'-dioxybiphenyl cyclotriphosphazenes (1a and 1b) with 2-hydroxybenzothiazole (2) were performed in the presence of metallic sodium in THF. Two novel 2-oxybenzothiazole-substituted spiro-2,2′-dioxybiphenyl cyclotriphosphazene derivatives (3a and 3b) were obtained from these reactions. Both compounds (3a, 3b) have been characterized by elemental analysis as well as by 1H, 13C and 31P NMR spectroscopy. Compounds 3a and 3b are reported for the first time in this study. [ABSTRACT FROM AUTHOR]

An efficient, highly convergent route for the synthesis of novel fourteen single isomer derivatives of ethyl-2-methyl-4-(pyridin-2-yl)-4H-benzo[4,5]thiazolo[3,2-a]pyrimidine-3-carboxylate have been developed by one-pot, three-component reaction between pyridine 2-aldehyde, β-ketoester and various derivatives of 2-amino benzothiazole in the presence of D-(+)-10-camphorsulphonic acid (D-(+)-10-CSA) as an effective chiral acid catalyst. Under the optimized conditions with 20 mol% catalyst loading, a wide range of optically active 4H-pyrimido[2,1-b]benzothiazole derivatives were obtained in good yields (up to 82%) with good to excellent enantioselectivities (84-99%ee). Their structures were elucidated by various spectroscopic methods such as 1H-NMR, 13C-NMR, Chiral HPLC, mass and elemental analysis. The attractive feature of this approach is one-pot synthesis, good yield, environment benign, mild reaction condition, simple, efficient, excellent stereoselectivity, water soluble catalyst and easy workup. All the final scaffolds have been screened for antibacterial activity. Among them, 4a', 4c', 4d', 4e', 4f', 4g', 4j',4m' and 4n' were proven to possess enhanced antibacterial properties as compared to the standard drug. [ABSTRACT FROM AUTHOR]

A series of novel pyridylpyrazole amide compounds which contain benzothiazole, thiourea, and urea moieties, respectively, were successfully synthesized. Their structures were confirmed by IR, 1H NMR, 13C NMR, and HRMS. Some of the compounds were found to have favorable insecticidal potentials; particularly, the insecticidal activities of 3-chloro-1-(3-chloropyridin-2-yl)-N-(6-(trifluoromethyl)benzo[d]thiazol-2-yl)-1H-pyrazole-5-carboxamide (3b), 1-(3-chloropyridin-2-yl)-N-(4,6-dichlorobenzo[d]thiazol-2-yl)-3-(trifluoromethyl)-1H-pyrazole-5-carboxamide (3g), 3-bromo-N-(4-chloro-2-(3-ethylthioureido)phenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide (6e), 3-bromo-N-(4-chloro-2-(3-isopropylthioureido)-6-methylphenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide (6g), 3-bromo-1-(3-chloropyridin-2-yl)-N-(2-(3-isopropylureido)-6-methylphenyl)-1H-pyrazole-5-carboxamide (7c), 3-bromo-N-(4-chloro-2-(3-isopropylureido)phenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide (7d), 3-bromo-N-(4-chloro-2-(3-isopropylureido)-6-methylphenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide (7f), and 3-bromo-N-(2-(3-(tert-butyl)ureido)-4-chloro-6-methylphenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide (7g) were close to and even superior to those of the insecticide triflumuron toward diamondback moth, and can be used as novel insecticidal leading structures for further investigations. Some of the compounds showed good fungicidal potentials against a broad spectrum of tested fungi including Sclerotinia sclerotiorum, Cercospora arachidicola, Physalospora piricala and Rhizoctonia cerealis, and were comparable with the commercial fungicide controls, among others, 3b, 3-bromo-1-(3-chloropyridin-2-yl)-N-(6-(trifluoromethyl)benzo[d]thiazol-2-yl)-1H-pyrazole-5-carboxamide (3d), and N-(4-chloro-2-methyl-6-(3-methylthioureido)phenyl)-1-(3-chloropyridin-2-yl)-3-(trifluoromethyl)-1H-pyrazole-5-carboxamide (6i) could serve as novel fungicidal leading compounds for further research. The structure-activity relationships were analyzed and discussed in detail. This research provides useful information for the design and discovery of novel insecticidal/fungicidal agents. [ABSTRACT FROM AUTHOR]

A simple and green method was developed for the reaction of 2-aminothiophenol and benzaldehyde in the self-neutralizing acidic CO2-alcohol system to produce benzothiazoles. A series of benzothiazole derivatives were successfully prepared from the condensation and cyclization reaction of 2-aminothiophenol or substituted 2-aminothiophenol with aliphatic, heteroaryl and aryl aldehydes promoted by alkyl carbonic acid under mild conditions. Moreover, the method is also suitable for the synthesis of 2-phenylbenzimidazole and 2-phenylbenzoxazole. Additionally, this reaction system greatly simplified post-processing, which did not need to be neutralized with base and without salt disposal. These advantages make the process more practical, economical, and environmentally friendly. Mechanism investigation indicated that formation of alkyl carbonic acid from CO2 and methanol is the key intermediate, which provides hydrogen ions to catalyze the reaction of 2-aminothiophenol and benzaldehyde. [ABSTRACT FROM AUTHOR]

A simple route for the synthesis of 2-aminophenyl benzothiazole through domino intra and inter molecular C-N cross-coupling reaction using a cobalt catalyst under mild reaction conditions has been accomplished. The procedure is experimentally simple, general, and efficient. All the substrates readily carried out under optimized reaction conditions to provide target products in moderate to good yield. [ABSTRACT FROM AUTHOR]

In this study, a novel series of benzothiazole-thiazolylhydrazine (3a–3i) was synthesized and their structures were characterized by 1H-NMR, 13C-NMR spectrometry, and mass spectroscopy. These compounds were evaluated as inhibitors of type A and type B monoamine oxidase (MAO) enzymes. The most active compound 3b (2-((2-(2-(4-(4-Nitrophenyl)thiazol-2-yl)hydrazineylidene)-2-phenylethyl)thio)benzothiazole) showed strong inhibitory activity at hMAO-A (IC50 of 0.095 ± 0.004 µM). Furthermore, compound 3i (2-((2-(2-(4-(2,4-dichlorophenyl)thiazol-2-yl)hydrazineylidene)-2-phenylethyl)thio)benzothiazole) showed significant inhibition profile on hMAO-A with the IC50 values 0.141 ± 0.006 µM. [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]

Sixteen new 2-(benzothiazol-2-ylthio)-N′-(3-substituted-4-(3,4-substitutedphenyl)thiazol-2(3H)-ylidene)acetohydrazide derivatives (4a-4p) were synthesized. The structures of the synthesized compounds were elucidated using FT-IR, 1H-NMR, 13C-NMR, and HRMS spectral data. Anticancer activity of the compounds 4a-4p against C6 (rat brain glioma) and A549 (human lung adenocarcinoma) cell lines was evaluated by using MTT, inhibition of DNA synthesis, and flow cytometric analysis assays. According to MTT assay, 4a and 4d were found to be the most active compounds against C6 cell line with an IC50 value of 0.03 mM. Moreover, IC50 values of 4a (0.2 mM) and 4d (0.1 mM) against NIH3T3 (mouse embryo fibroblast cell line) were higher than their IC50 values (0.03 mM) against C6 cell line. Accordingly, selectivity of compound 4a against C6 cell line was two-fold higher than that of compound 4d. Flow cytometry analysis showed that these compounds display anticancer activity by inducing apoptosis. As a result, compound 4a has a remarkable anticancer activity and a good selectivity towards C6 cell lines. [ABSTRACT FROM AUTHOR]

A novel benzothiazole derivativeJas a fluorescent chemosensor for Zn2+has been designed and synthesized. The chemosensorJexhibits high selectivity and sensitivity to Zn2+as fluorescence “turn-on” behavior, which the other cations do not make sense. The detection limit calculated by fluorescence titration method was 1.64 × 10−8M. Furthermore, the generatedJ-Zn2+ensemble could recover the enhanced fluorescence upon the addition of EDTA generating an “on-off-on” recycle. In addition, the test strip based onJwas fabricated, which could act as a convenient and efficient Zn2+test kit. [ABSTRACT FROM PUBLISHER]

2-Substituted benzothiazoles were synthesized through condensation of bis(2-aminophenyl) disulfides with arylaldehydes catalyzed by inexpensive NaSH in PEG-300 and assisted by low energy microwave irradiation(25 W). Various 2-substitutedbenzothiazoles were obtained in moderate to high yields after simple post-reaction processing including adding distilled water, filtrating, and drying. Moreover, it was found that the S-S bond of the disulfide was reduced by NaSH and also by the intermediate benzothiazoline. [ABSTRACT FROM PUBLISHER]

A series of novelN-pyridylpyrazolecarboxamides containing benzothiazole were designed and synthesized. The target compounds were identified by1H NMR,13C-NMR, IR, high-resolution mass spectrum (HRMS) and elemental analysis. The bioactivities of the new compounds against oriental army worm (Mythimnaseparata) and diamond back moth(Plutellaxylostella) were evaluated. The results of bioassays indicated that some of the compounds showed good activitiesat the tested concentrations. CompoundIjshowed 100% larvicidal activities againstPlutellaxylostellaat 2.5 mg/L, while the activity ofIjagainstMythimnaseparatawas 100% at 10 mg/L. [ABSTRACT FROM AUTHOR]

A series of diethyl/ethylphenyl {2-(benzo[d]thiazol-2-yl)phenylamino}phosphonates and phosphinates were synthesized under microwave irradiation and neat conditions via Kabachnik-Fields reaction in high yields (80%–93%). The compounds were screened for antimicrobial and antioxidant properties. A few compounds showed effective antibacterial and antifungal activities at MIC value 12.5 μg/mL as compared with the standard at MIC value 6.25 μg/mL. [ABSTRACT FROM AUTHOR]

The synthesis of 2-(substituted phenyl)-2-oxoethyl 4-(pyrimidin-2-yl)piperazin-1-carbodithiodate (A1-A24) derivatives and 2-(4-substituted thiazol-2-ylamino)-2-oxoethyl 4-(pyrimidin-2-yl)piperazin-1-carbodithiodate (B1-B14) derivatives was undertaken starting from the potassium salt of 4-(2-pyrimidinyl)piperazine dithiocarbamate. The structures of the obtained compounds were elucidated by1H NMR,13C NMR, MS spectral data, and elemental analysis. The antimicrobial activity of the thirty eight newly synthesized compounds were tested against 12 microorganism strains using the microdilution technique. Compounds 2-(4-ethoxycarbonylthiazol-2-ylamino)-2-oxoethyl 4-(pyrimidin-2-yl)piperazin-1-carbodithiodate (B12), 2-(3-fluorophenyl)-2-oxoethyl 4-(pyrimidin-2-yl)piperazin-1-carbodithiodate (A18) and 2-(3,4-difluorophenyl)-2-oxoethyl 4-(pyrimidin-2-yl)piperazin-1-carbodithiodate (A21) were determined to possess high antimicrobial activity. [ABSTRACT FROM AUTHOR]

Nano-titania-supported sulfonic acid (n-TSA) has been used as an efficient, inexpensive and reusable heterogeneous nano catalyst for synthesis of 2-arylbenzothiazole derivatives under solvent free condition. The reaction works very well, with good to excellent yields, for different aromatic aldehydes with both electron-withdrawing and electron-donating groups. Easy preparation and separation of catalyst, simply workup procedure, clean reaction, and reusability of the catalyst up to seven times without appreciable loss of its catalytic activity are undoubtful advantages of this work. [ABSTRACT FROM PUBLISHER]

The versatile multifunctional unreported 2-(phenylthiocarbamoyl)-N-(benzothiazol-2-yl)-3-phenyl-3-oxopropanamide was prepared from N-(benzothiazol-2-yl)-3-phenyl-3-oxopropanamide. Several new series of poly-substituted thiophenes and 1,3,4-thiadiazoles incorporating the N-(benzothiazol-2-yl)-3-oxo-3-phenylpropanamide moiety were efficiently synthesized. [ABSTRACT FROM AUTHOR]

A series of four different armed heterocyclic candidates; 1-(2-methyl-2,3-dihydro-1,3-benzothiazol-2-yl)acetone (2), 1-(3-methyl-4H-1,4-benzothiazin-2-yl)ethanone (3), 2-[(2-aminophenyl)dithio]aniline (4), and 3-hydroxy-3-methyl-4-(3-methyl-2-quinoxalinyl)-2-butanone (5) have been prepared and their microbial activities were evaluated. A correlation of the structure and activities relationships of these compounds with respect to molecular modeling, Lipinski Rule of Five, drug likeness, toxicity profiles, and other physico-chemical properties of drugs are described and verified experimentally. [ABSTRACT FROM AUTHOR]

A new series of 2-substituted-3-((3-(6-nitrobenzo[d]thiazol-2-yl)-4-oxo-3,4-dihydroquinazolin-2-yl)methyl)-1,3,4-thiadiazol-3-ium-5-thiolate6(a–j)was synthesized starting from anthranilic acid1. The structures of the newly synthesized compounds were characterized by IR,1H NMR,13C NMR, mass spectra, and elemental analysis. The final compounds were tested for their antimicrobial activity against several microbes. [Supplementary materials are available for this article. Go to the publisher's online edition ofPhosphorus, Sulfur, and Silicon and the Related Elementsfor the following free supplemental files: Additional text and tables.] [ABSTRACT FROM AUTHOR]

A series of 2-(arylthio)arylcyanamide derivatives were obtained in excellent yields via a copper-catalyzed domino C–S cross-coupling of 2-aminobenzothiazoles with aryl iodides. This reaction occurred via an intermolecular C–S bond formation, associated with C–S bond cleavage, followed by an intermolecular S-arylation under ligand-free conditions. Their structures were unambiguously determined by the analytic tools, such as HRMS,1H, and13C NMR analysis. [ABSTRACT FROM PUBLISHER]

A one-pot, efficient three-component condensation of aldehydes, 2-naphthol, and 2-aminobenzothiazole in the presence of sodium hydrogen sulfate as an effective catalyst for the synthesis of 1-(benzothiazolylamino)methyl-2-naphthol derivatives under thermal and solvent-free conditions is described. These products involve two biologically active parts, Betti's base and benzothiazole. The present methodology offers several advantages, such as good yields, short reaction times, and easy work-up. [ABSTRACT FROM AUTHOR]

3H-Benzothiazole-2-thione and 3H-benzoxazole-2-thione were selectively S-alkylated by use of O-alkylisoureas as the alkylating reagents. The reactions could be performed under mild reaction conditions in short reaction times, and high yields were obtained using O-primary-alkylisoureas, whereas low yields were obtained with sec- and tert-alkylisoureas. [ABSTRACT FROM PUBLISHER]

The Schiff bases derived from the condensation of 2-aminobenzothiazole derivatives and 2-hydroxy-3-methoxybenzaldehyde and their silicon(IV) complexes with the general formula R2Si(L)Cl (R = Et, Bu, Ph, L = 2-(2-hydroxy-3-methoxy) benzylideneaminobenzo-thiazole) have been synthesized. These complexes have been characterized by elemental analysis, molar conductance, and spectroscopic studies including IR and NMR (1H, 13C, and 29Si) spectroscopy. The analytical data suggest trigonal bipyramidal geometry around the silicon atom in the resulting complexes. The ligands and their organosilicon complexes have also been evaluated for in vitro antimicrobial activity against bacteria (Staphylococcus aureus, Bacillus subtilis, and Escherichia coli) and fungi (Aspergillus niger and Candida albicans). The complexes were found to be more potent as compared to the ligands. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM PUBLISHER]

A simple and efficient procedure has been developed for the synthesis of benzothiazole derivatives in water by the condensation of 2-aminothiophenol with aldehydes in the presence of Sulfonated porous carbon (SPC). This method provides a simple and efficient protocol in terms of mild reaction conditions, clean reaction profiles, small quantity of catalyst, and simple workup procedure. GRAPHICAL ABSTRACT [ABSTRACT FROM AUTHOR]

The synthesis of a series of novel α-aminophosphonate derivatives containing benzothiazole and thiourea moieties from substituted 2-aminobenzothiazoles and synthetic intermediates O,O′-dialkylisothiocyanat-(phenyl)methylphosphonates under microwave irradiation has been demonstrated. Several salient features, such as good to excellent yields, shorter reaction times, milder reaction conditions, and simple purification procedures, make the present synthetic protocol highly attractive to access the title compounds. Bioassays indicated that most of the compounds possessed broad-spectrum insecticidal and antiviral activities against Tobacco Mosaic Virus (TMV) in vivo. Interestingly, in comparison with control insecticide Avermectin, two compounds displayed remarkably high in vitro insecticidal activities against Plutella xylostella. Furthermore, according to the results from preliminary bioassay, all were associated with moderate to good anti-TMV activities. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Tables S1–S4. Figures S1–S52.] GRAPHICAL ABSTRACT [ABSTRACT FROM PUBLISHER]

2,4,6-Substituted 1,3,5-tris(benzothiazolyl)hexahydro-1,3,5-triazine derivatives were synthesized by the condensation of substituted benzothiazoles with aldehydes by conventional as well as by microwave irradiation (solvent free and solid supported) methods. All compounds were tested for antibacterial and antifungal activities, and the results have been compared with standard drugs. Acaricidal and anti-feedant activities were also tested. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM AUTHOR]

2-Furoyl isothiocyanate (1) is used as a building block in synthesizing different heterocyclic systems of anticipated biological activities. Thus, isothiocyanate 1 was reacted with different nucleophilic reagents to produce five- and six-membered heterocyclic systems such as 1,2,4-triazoline, thiadiazolidine, quinazoline, benzothiazole, benzoxazole, benzimidazole, thiazolidine, and imidazolidine. The structures of all the synthesized compounds were confirmed by microanalytical and spectral data. The antimicrobial activity of some of the synthesized compounds was tested. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM AUTHOR]

Cyanobenzothiazole (1) was utilized for the synthesis of several new fused and 2-heterylbenzothiazole derivatives such as pyrimido, pyridino, quinolino, pyrazolopyranyl, pyrimidinopyranyl, and cyclohexanopyranyl benzothiazole derivatives. [ABSTRACT FROM AUTHOR]

1,3,5-Tri(6-substituted benzothiazolyl)-2,4,6-substitutedhexahydro-1,3,5-s-triazine derivatives were synthesized by condensation of substituted benzothiazoles with aldehydes by conventional as well as microwave irradiation (solvent free and solid support) methods. All compounds were tested for antibacterial and antifungal activities, and results have been compared with standard drugs. Acaricidal and antifeedant activities were also tested. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM AUTHOR]

A mild and efficient methodology to produce 2-mercaptobenzothiazoles in DMF via ortho-haloaniline coupling with potassium O-ethyl dithiocarbonate catalyzed by copper without a ligand has been developed. [ABSTRACT FROM PUBLISHER]

2-Substituted benzothiazoles have been efficiently synthesized in good yields by the condensation reaction of o-aminothiophenol with aldehydes in the presence of a catalytic amount of perchloric acid-doped polyaniline (HClO4/PANI). The low cost, simple recovery, and efficient reusability are remarkable characteristics of this catalyst. [ABSTRACT FROM AUTHOR]

New Schiff base ligands (6-9) derived from 5-amino-4-phenyl-4H-1,2,4-triazole-3-thiol 1 and substituted benzaldehydes (2-5) as well as their metal complexes with Cu(II), Fe(II), Au(III), and Mn(II) (12-17) have been synthesized. A new benzothiazole derivative (11) was prepared from coupling of 7 with N-(benzothiazol-2-yl)-2-chloroacetamide 10. Their spectral properties were investigated. The newly designed and synthesized Schiff base ligands and the metal complexes were assayed for anti-HIV-1 and HIV-2 activity by examination of their inhibition of HIV-induced cytopathogenicity in MT-4 cells. Compounds 11 and 16 were found to be the most active inhibitors in cell culture (EC50 = 12.2 μg/mL (SI = 4) and > 2.11 μg/mL (SI = > 1), respectively) against HIV-1, whereas 11 showed inhibition against HIV-2 of EC50 > 10.2 μg/mL with SI = 9, which provided a good lead for further optimization. [ABSTRACT FROM AUTHOR]

A new series of 12-(2-chloro-6-quinoline-3-yl)-3,3,8-substituted-2,3,4,12-tetrahydro-benzo[4,5]thiazolo[2,3-b]quinazolin-1-ones 4 was synthesized in one pot by condensing various 2-chloro-3-formylquinolines 1, 2-amino-6-substituted-benzothiazoles 2, and 1,3-cyclohexanedione 3 in ethanol. All the compounds were characterized by IR, 1H NMR, 13C NMR spectra and elemental analysis. All the synthesized compounds were screened for their antibacterial activity against Grampositive bacterial species Bacillus cereus and Bacillus substilus, Gram-negative bacterial species Escherichia coli, and their fungicidal activity against Aspergillus niger, Fuserium oxisporum, and Rhizopus species. [ABSTRACT FROM AUTHOR]

The synthesis, biocidal activity, and spectroscopic data of a new series of S-phosphorylated/thiophosphorylated derivatives of 2-(2'-mercaptophenyl) benzothiazole are reported in this study. Derivatives were prepared by reacting 2-(2'-mercaptophenyl) benzothiazole with phosphorus oxychloride/phosphorus thiochloride in different molar ratios [1:1, 2:1, 3:1]. All of the derivatives were found to be antifungal agents with less toxicity than the standard Dithane M-45. [ABSTRACT FROM AUTHOR]

This review article includes the methods for the preparation of 2-cyanomethylbenzothiazole, its chemical reactivity towards different electrophiles and nucleophiles, and its use for the synthesis of heterocyclic compounds. Its biological activity and applications are also reported. This review includes 159 references. [ABSTRACT FROM AUTHOR]

Novel 1,2,4-triazine, pyridine, and benzopyran derivatives have been synthesized from N-(2-benzothiazolyl)cyanoacetamide via its reaction with some electrophiles. The structure of the synthesized compounds was established by analytical and spectral data. [ABSTRACT FROM AUTHOR]

2-Aminobenzothiazoles were efficiently synthesized using stable, crystalline tetrabutylammonium tribromide instead of toxic, corrosive liquid bromine under solvent-free and microwave irradiation condition. Furthermore, benzothiazol-2-ylureas were synthesized in good to high yield by reactions of 2-aminobenzothiazoles with N-trichloroacetanilides, which were used as a substitute for toxic, unstable isocyanates, under microwave irradiation condition. This protocol has advantages of no utilization of hazardous chemicals, rapid reaction rate, high yield, and easy work-up procedure. [ABSTRACT FROM AUTHOR]

The phosphorylated and thiophosphorylated benzothiazole derivatives have been synthesized by the reaction of phosphorus oxychloride/phosphorus thiochloride with 2-(2'-aminophenyl)benzothiazole in 1:1, 2:1, 3:1, and 1:2 molar ratios in presence of triethylamine. Plausible structures have been proposed on the basis of elemental analysis IR, 1H NMR, 31P NMR, and mass spectral studies. The fungicidal activity of these derivatives have been evaluated against pathogenic fungi Aspergillus niger and Fusarium oxysporium. The fungicidal data reveals that these compounds are more fungitoxic than the parent 2-(2'-aminophenyl)benzothiazole compound. [ABSTRACT FROM AUTHOR]

2-Cyanomethylbenzothiazole (1) was utilized for the synthesis of several new 2- heteryl benzothiazole derivatives as pyrazolyl, thienyl, pyridyl, benzoimidazolyl, and benzothiazolyl derivatives. [ABSTRACT FROM AUTHOR]

A series of 2,4,10a-triaryl-1,10a-dihydro-2H-pyrazino[2,1-b][1,3]benzothiazoles were prepared in good yields by the reaction of 2-[(2-oxo-2-arylethyl) anilino]-1-aryl-1-ethanones with 2-aminothiophenol in the presence of p-toluenesulfonic acid under solventless conditions. The products were characterized by 1H NMR and 13C NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Phosphorylated and thiophosphorylated benzothiazole derivatives have been synthesized by a reaction of phosphorus oxychloride/phosphorus thiochloride with 1,2-bis(2-benzothiazolyl)ethanol in 1:1, 1:2, and 1:3 molar ratios in the presence of triethylamine. Plausible structures have been proposed on the basis of elemental analysis IR, 1H NMR, and 31P NMR spectral studies. The fungicidal activity of these derivatives has been evaluated against pathogenic fungi Aspergillus niger and Fusarium oxysporium. The fungicidal data reveals that these compounds are more fungitoxic than the parent 1,2-bis(2-benzothiazolyl)ethanol compound. [ABSTRACT FROM AUTHOR]

Various 4-aryloxymethylcoumarins have been obtained by the r.t. allylic substitution with formylphenols. These have been further reacted with o-aminothiophenol resulting in the formation of a benzothiazole skeleton. These compounds have been synthesised with a view to study their potential as microbial growth inhibitors. Comparative studies on the spectral and antimicrobial activities have also been carried out. [ABSTRACT FROM AUTHOR]

Some complexes of 3-methyl-2-benzothiazolylidenamido thiophosphoryl dichloride (L 1 ), (3-methyl-2-benzothiazolylidenamido)–bis-(diethylamido) thiophosphate (L 2 ), 3-benzyl-2-benzothiazolylidenamido thiophosphoryl dichloride (L 3 ), and (3-benzyl-2-benzothiazolylidenamido)–bis-(diethylamido) thiophosphate (L 4 ) have been synthesized by a reaction with mercuric chloride in a 1:1 ratio. The complexes have been characterized by elemental analysis, electrical conductivity, and mass and IR spectral studies. The stability constants of these complexes have also been determined by a spectrophotometric technique and compared with zinc complexes of the previously discussed ligands. [ABSTRACT FROM AUTHOR]

2-(Benzo[d]thiazol-2-yl)-4-chloro-3-oxobutanenitrile (2) was utilized for the synthesis of several new benzothiazole derivatives. Compound 2 reacted with aniline, hydrazine hydrate, ethanolamine, and ethyl glycinate hydrochloride to yield benzothiazole derivatives 3–6, respectively. [ABSTRACT FROM AUTHOR]

New tetracoordinated complexes of Zn (II) have been synthesized by the reaction between zinc chloride and 3-methyl-2-benzothiazolylidenamido-thiophosphoryl dichloride (L 1 ), (3-methyl-2-benzothiazolylidenamido)-bis-(diethylamido)thiophosphate (L 2 ), 3-benzyl-2-benzothiazolylidenamido thiophosphoryl dichloride (L 3 ), and (3-benzyl-2-benzothiazolylidenamido)-bis-(diethyl-amido) thiophosphate (L 4 ) in a 1:1 ratio. The complexes have been isolated and characterized by elemental analysis, electrical conductivity, and mass and IR spectral studies. The stability constants of these complexes also have been determined in aqueous solution by spectrophotometric methods. [ABSTRACT FROM AUTHOR]

2-Substituted benzothiazoles (3a–h) were prepared from the condensation reaction of 2-aminothiophenol 1 with aldehydes 2 in the presence of P-Ts-OH and graphite on the surface of solid mineral supports without using any oxidizing agent under microwave irradiation. [ABSTRACT FROM AUTHOR]

Some 2-[(benzazole-2-yl)thio]diphenylmethylacetamide[3pc] derivatives were synthesized by reacting 2-chloroacethylaminodiphenylmethane with benzazole-2-thions. The structure elucidation of the compounds was performed by IR,1H NMR, and MS-FAB spectral data.Antimicrobial activity of the compounds was examined. Some of the compounds have shown similar antifungal activities against C. albicans when compared with ketoconazole. It was also observed that some of these compounds have moderate antimicrobial activity when compared with chloramphenicole. [ABSTRACT FROM AUTHOR]

Fostedil (diethyl 4-(benzothiazol-2-yl) benzylphosphonate)7has been synthesized efficiently by treatment of 2-(4-bromomethylphenyl) benzothiazole6with triethylphosphite. The latter (6) has been prepared by bromation of benzothiazole3c. N-acylimidates1(a–d)react with 2-aminobenzenethiol2to lead to the corresponding benzothiazoles3(a–d)after elimination of primary amide5. The structure of these products have been unequivocally confirmed by means of IR,1H,13C, and31P NMR spectroscopy and mass spectra. [ABSTRACT FROM AUTHOR]

Interaction of 1,4-phenylenediisothiocyanate 1 with aromatic amines and o-phenylenediamine furnished the novel bisthiourea derivatives 2a-c and 7 . Hydrazines or o-aminothiophenol reacted with 1 to produce bis-(thiosemicarbazide 4a,b or benzothiazole 9 ) derivatives. Bisquinazolines 12a,b and bisthienopyrimidines 13a,b were synthesized through interaction of 1 with anthranilic acids 10a,b and aminothiophenes 11a,b . Interaction of 1 with two moles of either salicylic acid or N-(4-substituted-phenyl)cyanothioformamide yielded the corresponding bis(1,3-benzoxazine 14 or imidazolidineiminothiones 16 ) derivatives. [ABSTRACT FROM AUTHOR]

New azo sulfadrugs of 2-mercapto-S-azo ( p ′-heterocyclo-substituted benzene-sulfonyl) benzothiazole derivatives (L 1 and L 2 ) were synthesized by coupling of p ′-heterocyclo-substituted-benzene-sulphonyl diazonium salts with 2-mercapto-benzothiazole in acid medium. The corresponding iron(III), cobalt(II), nickel(II), copper(II), and mercury(II) chelates were prepared in a 1:1 metal to ligand molar ratio. The ligands and their chelates were characterized on the basis of microanalysis, UV, IR, and H 1 -NMR spectrometry. Thermal decomposition of the complexes was studied in static air. On the basis of the thermogravimetric curves some decomposition steps could be correlated with the proper decomposition products. The photochemical behavior of the ligands and their complexes were investigated. The photosensitivity shown by the complexes was attributed to the photoreactivity of their free ligands. The ligands and their chelates were screened in vitro for their antimicrobial activities (antibacterial and antifungal). The complexes induce a remarkable increase in the antimicrobial activity compared to the corresponding ligands. [ABSTRACT FROM AUTHOR]

2-Cyano-2-nitrosomethylbenzthiazole reacts with some active methylene and nucleophile derivatives to yield new fused and isolated polyfunctional pyrazine, -[1,2,4]triazine, -[1,4,5]benzoxadiazepin, -[1,4,5]benzothiadiazepine, [1,4,5]benzotriazepine, -triazole and -triazolo[3,2-c]triazine derivatives in one-pot reaction. The structures were based on IR, MS, and 1 H NMR spectra and elemental data. [ABSTRACT FROM AUTHOR]