Synthesis and Biological Evaluation of novel Quinoxaline containing N-substituted thiazolidine-2,4-dione derivatives as Anti-cancer Agents

Introduction: Quinoxalines belong to the N-containing heterocyclic compounds that stand out as having promising biological activity due to their privileged scaffold. Quinoxaline derivatives constitute the basis of many insecticides, fungicides, herbicides, as well as being important in human health and as receptor antagonists. On the other, the compounds containing thiazolidine-2,4-dione have demonstrated wide range of pharmacological activities, which include antimicrobial, antiviral, antidiabetic and anticancer activity. In this research, we have synthesised a new quinoxaline derivatives containing N-substituted thiazolidine-2,4-dione derivatives and evaluated for antitumor activity against a 3-cell line panel, consisting of MCF7 (breast), NCI-H460 (lung), and SF-268 (CNS). Methods and Results: In a 250 ml three necked flask equipped with teflon coated mechanical stir bar, chloroacetic acid and thiourea have been dissolved in distilled water and the contents of the flask were heated in the presence of hydrochloric acid. The precipitate was filtered and washed with water and dried before recrystalization. Consequently, the new synthesized thiazolidinedione derivatives were condensed in situ by quinoxaline aldehydes and substituted benzyl halides in N,N-Dimethylformamide. The resulted products were washed with water and then recrystallized in appropriate solvent. Structures of all the synthesized compounds were confirmed by IR, 1H NMR, 13CNMR, and Mass spectral data. The MTT assay of synthesized hybrids showed promising and effective anti-cancer activity against 3-cell cell lines. The current results indicate that these quinoxaline derivatives are novel and promising agents for further development towards a treatment for cancer. conclusion: In the present study, series of new N-thiazolidine-2,4-dione incorporated quinoxaline ring were synthesized. All compounds were screened against two different cancer cell lines using MTT assay method

Synthesis of New Derivative of pyrazolo[4,5-b]quinoxaline Bearing imidazolidine-2,4-dione as a Potential Anticancer Agent

Introduction: Among heterocyclic anticancer compounds, quinoxalines and imidazolidine-2,4-dione are the most prominent since they constitute important classes of natural products and synthetic pharmaceuticals. In general, they are used as valuable intermediates and building blocks in pharmaceutical synthesis. Therefore, much attention has been paid to the synthesis of quinoxaline derivatives bearing imidazolidine-2,4-dione either by classic methods or by multicomponent reactions.  Methods and Results: The title compound was prepared through a three- step procedure. In the first step, equimolar amounts of D-glucose and o-phenylenediamine were reacted with phenyl hydrazine in the presence of acetic acid, to form the pyrazolo[4,5-b]quinoxaline  derivative. The second step involved oxidation of the resulted compound by use of sodium metaperioddate. Finally, the related aldehyde was condensed by imidazolidine-2,4-dione to yield the corresponding 3-alkylidene pyrazolo[4,5-b]quinoxaline . Conclusions: The procedure applied in this study established a convenient method for the preparation of the title compounds. The process was straight forward and it used abundant and readily available staring materials. Due to its chemical structure, and in particular the presence of the quinioxaline ring, which is a commonly encountered motif in compounds of medicinal interest, the prepared product is expected to show anticancer activity

Bioremediation of methyl tertiary-butyl ether (MTBE) by three pure bacterial cultures

Background: Bioremediation of groundwater and soil contamination is more economical than physicochemical remediation. The present study focused on the bioremediation capability of two bacterial species (Klebsiella planticola and Enterobacter cloacae) from the family Enterobacteriaceae. These bacteria have been identified as new species with capability of degrading methyl tertiary-butyl ether (MTBE). In order to enhance their degradation capability, selected concentrations and retention time were investigated. Methods: The bacteria were cultured on the nutrient agar (NA) medium at room temperature. pH of the medium was adjusted to 7. The medium was autoclaved at 121°C for 15 minutes and incubated for 24 hours at 35°C. After 24 hours, the mixture was inoculated into 50 mL of Luria Bertani (LB) liquid medium containing 50 and 150 ppm MTBE. The cultures were incubated for 2 and 5 days at 35°C and shacked on a shaker at 150 rpm. Cell concentrations of the bacteria in pure culture were determined from the optical density at 600 nm using a UV–VIS spectrophotometer. Then, the culture was centrifuged at 3800 rpm for 20 minutes. In the next step, the MTBE concentration in the supernatant was measured by gas chromatography/mass spectrometry (GC/MS, Agilent Technologies, 5975, US10304411, 5.02.07). Results: The results showed that both strains are able to grow in the presence of 50 and 150 ppm MTBE. In the best conditions, when cell density was 3×108 CFU/mL during 5 days, the highest rate of MTBE degradation for K. planticola and E. cloacae, was 43% and 40%, respectively. It was also revealed that Escherichia coli can degrade 50 and 150 ppm MTBE about 19.8% and 13.65%, respectively. Conclusion: It seems that E. coli can be a good candidate for MTBE degradation at high concentrations for a time longer than that in the present study. It was also found that the species have high performance at 50 ppm than 150 ppm. So, these bacteria can remove MTBE from the environment. Keywords: Biodegradation, Klebsiella planticola, Enterobacter cloacae, Escherichia coli, methyl tertiarybutyl ethe

Troubling the notion of satisfied students

This paper investigates whether students’ personal happiness is different from student satisfaction and considers if this may have consequences for university policy and management. It does this by comparing happiness and satisfaction in two cohorts of students from two United Kingdom universities. One is a distinctive research university and the other a university whose heritage has been in the polytechnic sector prior to its charter, referred to as a post-1992 university. The results, although preliminary, do appear to show that satisfied students are also happy students. However, what contributes to these states of being is different. The implication for institutional policy is discussed and a warning that to assume satisfaction (measured by satisfaction survey results) as happiness might be problematic in addressing improvement in the student experience

Construct-level predictive validity of educational attainment and intellectual aptitude tests in medical student selection: meta-regression of six UK longitudinal studies

Background: Measures used for medical student selection should predict future performance during training. A problem for any selection study is that predictor-outcome correlations are known only in those who have been selected, whereas selectors need to know how measures would predict in the entire pool of applicants. That problem of interpretation can be solved by calculating construct-level predictive validity, an estimate of true predictor-outcome correlation across the range of applicant abilities. Methods: Construct-level predictive validities were calculated in six cohort studies of medical student selection and training (student entry, 1972 to 2009) for a range of predictors, including A-levels, General Certificates of Secondary Education (GCSEs)/O-levels, and aptitude tests (AH5 and UK Clinical Aptitude Test (UKCAT)). Outcomes included undergraduate basic medical science and finals assessments, as well as postgraduate measures of Membership of the Royal Colleges of Physicians of the United Kingdom (MRCP(UK)) performance and entry in the Specialist Register. Construct-level predictive validity was calculated with the method of Hunter, Schmidt and Le (2006), adapted to correct for right-censorship of examination results due to grade inflation. Results: Meta-regression analyzed 57 separate predictor-outcome correlations (POCs) and construct-level predictive validities (CLPVs). Mean CLPVs are substantially higher (.450) than mean POCs (.171). Mean CLPVs for first-year examinations, were high for A-levels (.809; CI: .501 to .935), and lower for GCSEs/O-levels (.332; CI: .024 to .583) and UKCAT (mean = .245; CI: .207 to .276). A-levels had higher CLPVs for all undergraduate and postgraduate assessments than did GCSEs/O-levels and intellectual aptitude tests. CLPVs of educational attainment measures decline somewhat during training, but continue to predict postgraduate performance. Intellectual aptitude tests have lower CLPVs than A-levels or GCSEs/O-levels. Conclusions: Educational attainment has strong CLPVs for undergraduate and postgraduate performance, accounting for perhaps 65% of true variance in first year performance. Such CLPVs justify the use of educational attainment measure in selection, but also raise a key theoretical question concerning the remaining 35% of variance (and measurement error, range restriction and right-censorship have been taken into account). Just as in astrophysics, ‘dark matter’ and ‘dark energy’ are posited to balance various theoretical equations, so medical student selection must also have its ‘dark variance’, whose nature is not yet properly characterized, but explains a third of the variation in performance during training. Some variance probably relates to factors which are unpredictable at selection, such as illness or other life events, but some is probably also associated with factors such as personality, motivation or study skills

The elite brain drain

We collect data on the movement and productivity of elite scientists. Their mobility is remarkable: nearly half of the world’s most-cited physicists work outside their country of birth. We show they migrate systematically towards nations with large R&D spending. Our study cannot adjudicate on whether migration improves scientists’ productivity, but we find that movers and stayers have identical h-index citations scores. Immigrants in the UK and US now win Nobel Prizes proportionately less often than earlier. US residents’ h-indexes are relatively high. We describe a framework where a key role is played by low mobility costs in the modern world

BME academic flight from UK to overseas higher education: aspects of marginalisation and exclusion.

This paper describes the experiences of BME academics who consider moving overseas for career opportunities. It explores the barriers that BME academics report in UK higher education, which affects their decisions for overseas higher education migration. Our findings suggest that BME academics were significantly more likely than White academics to have ever considered moving overseas to work, although reasons such as family commitments led to many remaining in the UK. However, those BME academics who eventually move overseas report positive experiences. In contrast those who stay in the UK report various barriers to career progression. We suggest significant change is needed in the UK higher education sector in order to retain BME academics who consider moving overseas. <br/