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p. 827-836
Received: 5 October 2006; in revised form: 22 October 2006 / Accepted: 23 October 2006 / Published: 1 November 2006
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| Download PDF Full-text (104 KB) Abstract: The new compound 7-methylpyrazolo[4,5-e][1,2,4]thiadiazin-3(2H,4H)-one1,1-dioxide (5) was synthesized and its novel mono N2 - or N4 -substituted derivatives 6and 7 were prepared by regioselective N-alkylation of 5 with different molar ratios ofNaH and alkyl halides. Based on the regioselective alkylation conditions found a facileone-pot synthesis of N2 ,N4 -disubstituted pyrazolo[4,5-e][1,2,4] thiadiazines 8 wasdeveloped. The structures of the newly synthesized compounds were confirmed by IR,1 H-NMR, 13 C-NMR and MS spectral analysis.
p. 837-848
Received: 6 October 2006; in revised form: 25 October 2006 / Accepted: 25 October 2006 / Published: 1 November 2006
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| Download PDF Full-text (103 KB) Abstract: 3,5-Disubstituted hydantoin (1,3-imidazolidinedione) derivatives 5a-h wereprepared by base induced cyclization of the corresponding N-(1-benzotriazolecarbonyl)-L-and D-amino acid amides 4a-h. Compounds 5a-h were evaluated for their cytostatic andantiviral activities. Among all the compounds evaluated, 3-benzhydryl-5-isopropylhydantoin (5a) showed a weak but selective inhibitory effect against vaccinia virus (EC50 =16 μg/mL; selectivity index: 25). 3-Cyclohexyl-5-phenyl hydantoin (5g) showed inhibitoryactivity against cervical carcinoma (HeLa, IC50 = 5.4 μM) and breast carcinoma (MCF-7,IC50 = 2 μM), but also cytotoxic effects towards human normal fibroblasts (WI 38). On thecontrary, the 3-benzhydryl-5-phenyl substituted hydantoin derivative 5h showed moderateinhibitory activity towards HeLa, MCF-7, pancreatic carcinoma (MiaPaCa-2), lungcarcinoma (H 460) and colon carcinoma (SW 620) (IC50 = 20−23 μM), but no effect on WI38.
p. 849-857
Received: 27 September 2006; in revised form: 26 October 2006 / Accepted: 27 October 2006 / Published: 2 November 2006
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| Download PDF Full-text (99 KB) Abstract: A series of new 4β-5-Fu-substituted 4'-demethylepipodophyllotoxin derivatives were synthesized and evaluated, together with some previously prepared ones, for their cytotoxic activities against four tumor cell lines (HL60, P388, A549 and BEL7402). Three of these compounds exhibited superior in vitro anticancer activity against P388 and A549 than the reference compound etoposide. In addition, the partition coefficients (P) of all the new and previously synthesized derivatives were determined.
p. 858-866
Received: 13 September 2006; in revised form: 9 October 2006 / Accepted: 10 October 2006 / Published: 11 November 2006
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| Download PDF Full-text (65 KB) Abstract: The reaction between diaminomaleonitrile (DAMN) and aldehydes and the resulting monoimines are well known. Since the standard reaction conditions involve the use of toxic solvents (typically methanol), we have sought to apply green chemistry principles to this reaction by either using water as the solvent without any catalysts or employing “solvent-free” conditions. The monoimines derived from DAMN are of interest as precursors for obtaining different heterocyclic systems and linear polymers. The methodologies used have significant advantages with regards to cost and environmental considerations.
p. 867-889
Received: 4 October 2006; in revised form: 30 October 2006 / Accepted: 13 November 2006 / Published: 14 November 2006
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| Download PDF Full-text (171 KB) Abstract: A series of indazoles substituted at the N-1 and N-2 positions with ester-containing side chains -(CH2 )n CO2 R of different lengths (n = 0-6, 9, 10) are described.Nucleophilic substitution reactions on halo esters (X(CH2 )n CO2 R) by 1H-indazole inalkaline solution lead to mixtures of N-1 and N-2 isomers, in which the N-1 isomerpredominates. Basic hydrolysis of the ester derivatives allowed the synthesis of thecorresponding indazole carboxylic acids. All compounds were fully characterised bymultinuclear NMR and IR spectroscopies, MS spectrometry and elemental analysis; theNMR spectroscopic data were used for structural assignment of the N-1 and N-2 isomers.The molecular structure of indazol-2-yl-acetic acid (5b) was determined by X-raydiffraction, which shows a supramolecular architecture involving O2-H...N1intermolecular hydrogen bonds.
p. 890-903
Received: 18 October 2006; in revised form: 7 November 2006 / Accepted: 7 November 2006 / Published: 17 November 2006
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| Download PDF Full-text (145 KB) Abstract: 2–Amino–4-phenyl–5,6,7,8–tetrahydroquinoline–3–carbonitrile (3) was synthesized by treating cyclohexanone (1) with 2–benzylidenemalononitrile (2) in the presence of ammonium acetate. The reactivity of compound 3 towards dimethylformamide dimethyl acetal (DMF-DMA), carbon disulfide, urea, thiourea, formamide, formic acid, acetyl chloride and isothiocyanate were studied. In addition, the antimicrobial activity of some selected derivatives is reported.
p. 904-914
Received: 9 August 2006; in revised form: 22 September 2006 / Accepted: 5 November 2006 / Published: 17 November 2006
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| Download PDF Full-text (163 KB) Abstract: The synthesis of Cu(II) complexes derived from Schiff base ligands obtainedby the condensation of 2-hydroxybenzaldehyde or terephtalic aldehyde with 4-amino-antipyrine (4-amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one) is presented. The newlyprepared compounds were characterized by 1 H-NMR, UV-VIS, IR and ESRspectroscopy. The determination of the antimicrobial activity of the ligands and of thecomplexes was carried out on samples of Escherichia coli, Klebsiella pneumoniae,Acinetobacter boumanii, Pseudomonas aeruginosa, Staphylococcus aureus and Candidasp. The qualitative and quantitative antimicrobial activity test results proved that all theprepared complexes are very active, especially against samples of Ps. aeruginosa, A.Boumanii, E. coli and S. aureus.
p. 915-928
Received: 8 November 2006; in revised form: 28 November 2006 / Accepted: 28 November 2006 / Published: 29 November 2006
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| Download PDF Full-text (100 KB) Abstract: This work deals with the use of organic systematic nomenclature in scientific literature, its quality, and computerized methods for its improvement. Criteria for classification of systematic names in terms of quality/correctness are discussed and applied to a sample set of several hundred names extracted from the literature. The same structures are named with three popular state-of-the-art nomenclature programs – AutoNom 2000, ChemDraw 10.0, and ACD/Name 9.0. When comparing the results, all nomenclature tools show a significantly better performance than 'average chemists'. One program allows the generation not only of IUPAC names but also of CAS-like index names that are compared with the officially registered names. The scope and limitations of nomenclature software are discussed and a comparison of the programs' actual capabilities is given.
p. 929-939
Received: 2 November 2006; in revised form: 29 November 2006 / Accepted: 29 November 2006 / Published: 30 November 2006
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| Download PDF Full-text (91 KB) Abstract: The reactivity of 6-(nitrophenyl or trimethoxyphenyl)-4-tert-butyldimethyl- siloxy-1,2,3,6-tetrahydropyridine derivatives with hydrazines under acid conditions is described. The structure of the products isolated − hydrazones, pyrazolines or pyridazinones − depended on the conditions used. In addition, a systematic study of the reaction outcomes was carried out by introducing variations on the substituents of the tetrahydropyridine ring.
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