Nano-TiO2 as a novel and efficient catalyst for the synthesis of pyridine dicarbonitriles

Pyridine dicarbonitriles have been synthesized in good yields via a one-pot multi–component reaction of aldehyde, malononitrile, and thiol in the presence of nano-TiO2 as a catalyst in ethanol. KEY WORDS: Pyridine dicarbonitriles, Multi–component reaction, One-pot, Nano-TiO2 Bull. Chem. Soc. Ethiop. 2014, 28(1), 149-153.DOI: http://dx.doi.org/10.4314/bcse.v28i1.1

Potassium hydrogen sulfate: An efficient catalyst in organic reactions

Potassium hydrogen sulfate, KHSO4, has been used in many organic preparations as a good solid catalyst. The KHSO4 has received considerable attention since it is an inexpensive, eco-friendly, highly reactive, easy to handle and non-toxic catalyst for various organic transformations, affording the corresponding products in excellent yields with high selectivity. We wish to report some applications of this catalyst in organic reactions

Investigating perceived digital literacy skills of master students: A case study at the University of Social Welfare and Rehabilitation Sciences

Introduction: Researchers and students, who play an essential role in promoting education and research, must inevitably use various information sources to obtain information in order to meet their information needs. However, to use digital resources, they need the ability to use digital technology, referred to as digital literacy . Objectives: This research aimed to examine the digital information behaviour and digital literacy of master\u27s students at the University of Social Welfare and Rehabilitation Sciences. On this basis, it will be possible to determine web users\u27 level of expertise and knowledge in utilizing the information available on the web. By determining the current situation, appropriate solutions and training will be provided to improve the information behaviour of this group. Methods: This study cross-sectional study was carried out using a five-point Likert questionnaire developed by the researchers. The population of this study comprises 36 master\u27s students at the University of Welfare and Rehabilitation Sciences. Results: The results of this study revealed that the digital information-seeking ability and literacy of students at the University of Welfare and Rehabilitation Sciences are generally weak. Conclusion: It is advised that internet search training sessions be offered to the students and that the degree of development in their abilities is closely studied so that their inability to locate information using online resources may be precisely discovered. A timely subscription of databases, as well as an increase in periodical subscriptions based on the user demands, seem to be necessary

Molecular assessment of clarithromycin resistant Helicobacter pylori strains using rapid and accurate PCR-RFLP method in gastric specimens in Iran

Currently, a seven-day, triple-drug regimen has been recommended as one of the first-line therapies for Helicobacter pylori management in which clarithromycin is a key component. Development of clarithromycin resistance leads to the long term assessment of the efficacy of clarithromycin in the triple-drug regimen. The aim of this study was to rapidly and directly assess clarithromycin resistance point mutations on gastric biopsy specimens by using PCR-RFLP method. Biopsy samples were obtained over a 6-months period of 2009, from 200 dyspeptic patients referred to Shahrekord University of Medical Sciences, Iran. Initially, rapid urease test was performed and then DNA was isolated from each tissue and used for molecular analysis such as PCR (for H. pylori diagnostic) and PCR-RFLP (for Cla resistance determination). RUT and PCR results showed that 164 (82%) of the patients were H. pylori-positive. Resistance was evaluated in 164 samples by using enzymes BsaI and MboII. Thirty nine (39) (23/78%) clarithromycin-resistant strains were detected which were identified as 15 (9.15%) A2143G, 15 (9.15%) A2142G and 9 (5.49%) mix strains. The results showed that PCR-RFLP method had a high accuracy to detect A2142G and A2143G mutations associated with resistance to clarithromycin in the minimum possible time.Key words: Helicobacter pylori, clarithromycin resistance, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)

DABCO as a novel and efficient catalyst for the synthesis of 4(3H)-quinazolinone derivatives

4(3H)-Quinazolinones were synthesized in high to excellent yields through the one-pot condensation of anthranilic acid, trimethyl orthoformate and primary amines in the presence of DABCO under solvent free conditions.KEY WORDS: 4(3H)-Quinazolinone, DABCO (1,4-diazabicyclo[2,2,2]octane), Trimethyl orthoformate, Anthranilic acid Bull. Chem. Soc. Ethiop. 2011, 25(2), 305-308

Mesoporous molecular sieve MCM-41 catalyzed one-pot synthesis of 3,4-dihydro-2(1H)-pyrimidinones and –thiones under solvent-free conditions

An efficient synthesis of 3,4-dihydro-2(1H)-pyrimidinones and -thiones using MCM-41 as the catalyst from an aldehyde, β-keto ester, and urea or thiourea under solvent-free conditions is described.KEY WORDS: Biginelli reaction, Dihydropyrimidinones, MCM-41, One-pot, Reusable Bull. Chem. Soc. Ethiop. 2011, 25(2), 309-313