Template synthesis of N,N′-bis(4-acetyl-5-methylpyrazole-3-yl)formamidine (ampf) was performed starting from 4-acetyl-3-amino-5-methylpyrazole (aamp) and CH(OC2H5)3 in methanol in the presence of CuCl2, Cu(NO3)2, or Ni(NO3)2. The ligand was isolated in coordinated form as [Cu(ampf)Cl2], [Cu(ampf)(MeOH)(NO3)2]MeOH, and [Ni(ampf)(MeOH)2(NO3)]NO3 correspondingly. The compounds were characterized by elemental analysis, Fourier-transform IR and electronic spectroscopy, thermal analysis, single-crystal X-ray diffraction, and quantum chemical (density functional theory) calculations. The density functional theory calculations provided information on the metal–ligand interactions in the complexes and assisted the assignment of the FT-IR spectra. The antiproliferative activity of the complexes and the ligand precursor, aamp, was tested against human myelogenous leukaemia K562, colon adenocarcinoma HT29, and cervix carcinoma HeLa.

Starting from the D-glucose derivative (I), a total synthesis of (+)-crassalactone B (VI) and a new synthesis of (+)-crassalactone C (VII) is presented.

Department of Chemistry, Faculty of Sciences, University of Kragujevac, 34000 Kragujevac, Serbia Institute of Oncology Sremska Kamenica, Institutski put 4, 21204 Sremska Kamenica, Serbia Department of Chemistry, Faculty of Sciences, University of Novi Sad, 21000 Novi Sad, Serbia Faculty of Chemistry, University of Belgrade, 11000 Belgrade, Serbia *E-mail: mjoksovic@kg.ac.rs Received October 19, 2009 DOI 10.1002/jhet.400 Published online 8 June 2010 in Wiley InterScience (www.interscience.wiley.com).

INTRODUCTION In the last 15 years, the introduction of molecular biology methods and techniques for identifying mutations and measuring gene expression levels of mutated genes since recently, have enabled precise molecular diagnostics, classification and assessment of prognosis and therapeutic response of malignant disease to specific therapies. The increased knowledge of the cancer genome and the introduction of multiple new technologies in cancer research have significantly improved the drug discovery process, leading to key success in targeted cancer therapeutics, including tyrosine kinase inhibitors. Tyrosine kinase inhibitors are the molecular targeted neoadjuvant and adjuvant therapy of various malignancies. Many more results which are expected from ongoing trials are necessary to specify the appropriate dosages, stages at which to start the treatment, and which therapeutic combinations to apply.

In this study we investigated antioxidative and antiproliferative activity of different horsetail (Equisetum arvense L.) extracts. The antioxidative activity was measured by the electron spin resonance (ESR) spectroscopy-spin trapping method. The influence of different horsetail extracts during lipid peroxidation of (1) sunflower oil induced by the lipophilic azo-initiator 4,4'-azobis(4-cyanovaleric acid) and (2) soybean phosphatidylcholine liposomes induced by the hydrophilic azo-initiator 2,2'-azobis(2-amidinopropane) dihydrochloride was studied. Antiproliferative activity was measured using the sulforhodamine B colorimetric assay on the human cancer cell lines HeLa, HT-29, and MCF7. The results of ESR analysis confirmed that the extracts investigated suppressed the formation of lipid peroxyl radicals in both systems investigated in a dose-dependent manner. The results indicate that n-butanol, methanol, ethyl acetate, and water extracts had significant peroxyl radical scavenging activity. Extracts inhibited cell growth that was dependent on cell line, type of extract, and extract concentration. Ethyl acetate extract exhibited the most prominent antiproliferative effect, without inducing any cell growth stimulation on human tumor cell lines. The results obtained suggest that the horsetail extracts could be used as an easily accessible source of natural antioxidants and as potential phytochemicals.

Background:In search of a proposed viral aetiology of childhood acute lymphoblastic leukaemia (ALL), the common species C adenoviruses were analysed in Guthrie cards.Methods:Guthrie cards from 243 children who later developed ALL and from 486 matched controls were collected and analysed by nested polymerase chain reaction for the presence of adenovirus DNA.Results:Adenovirus DNA was reliably detected from only two subjects, both of whom developed ALL.Conclusion:Adenovirus DNA is detected in Guthrie card samples at too low a frequency to reveal an association between adenovirus and the development of leukaemia.