Synthesis and spectroscopic analysis of Schiff Bases of Imesatin and Isatin derivatives

A series of new Schiff bases of Imesatin and Isatin derivatives which have been previously prepared from the reaction of Hydrazine monohydrate, p-phenylenediamine and 4,4- diaminodiphenylmethane with Isatin were reported. The compounds were characterized by elemental analyses, UV-visible, Infrared and Nuclear Magnetic Resonance (1H NMR and 13C NMR) spectroscopic analyses. The synthesized Schiff bases were obtained in moderate to excellent yields between 55.3 – 89.3%. Infrared spectra of all synthesized compounds contain the characteristic azomethine linkage (-CH=N) between 1580 – 1630 cm-1 and the N–H of the Isatin ring signals between δ 8.32 – 10.68 ppm in their 1H NMR spectra. The present work affords reaction pathway that is efficient and operational simplicity for the synthesis of Schiff bases derivatives.Keywords: Schiff bases, isatin, imesatin, spectroscopic analysis, biological activit

GC-MS Analysis, Antimicrobial and Antioxidant Activities of Extracts of the Aerial Parts of Conyza sumatrensis

Phytochemical analyses as well as antimicrobial and antioxidant activities of the extracts of C. sumatrensis aerial parts were investigated in this study. METHODS: The aerial parts of C. sumatrensis were air dried, weighed and exhaustively extracted with hexane, ethyl acetate and methanol successively. The crude extracts were screened for metabolites.  These extracts of the plant were evaluated for antimicrobial and antioxidant activities using agar  diffusion and DPPH method respectively. The extracts were also analysed using Gas chromatography – Mass spectrometry, and the chromatogram coupled with mass spectra of the compounds were matched with a standard library. RESULTS: Preliminary phytochemical investigation of  rude n-hexane, ethyl acetate and methanol extracts of the aerial parts of Conyza sumatrensis revealed the presence of anthraquinones, flavonoids, terpenoids, phenolics, tannin, glycosides and carbohydrate. All the crude  extracts gave a clear zone of inhibition against the growth of the test bacteria (Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomona aeruginosa, Salmonella typhi, Klebsiellae pneumonae) at moderate to high  concentrations, as well as test fungi (Candida albicans, Aspergillus niger, penicillium notatum and  Rhizopus stolonifer) at high concentration. Methanolic extract exhibited significant radical scavenging  property with IC50 of 17.08 μg/mL while n-hexane and ethyl acetate extracts showed no significant antioxidant activity. GC-MS of N-hexane extract showed a total number of eleven chemical constituents with α-Farnesene and spathulenol being the most abundance compounds constituting 20.27 and 22.28% of the extract respectively. Ethyl acetate extract revealed thirteen  compounds with two most abundant compounds, cis-β-farnesene (16.64 %) and cis-pinane (21.09 %). While  methanolic extract affords seventeen compounds with Ephytol being the most abundant compound  (19.36 %). © JASEMKeywords: Antimicrobial activity, Antioxidant, GC-MS analysis, Phytochemicals, Conyza sumatrensi

COVID-19

The anxiety and trauma associated with the tragic coronavirus disease pandemic coded, COVID-19 led many to indulge in various unorthodox preventive measures such as the extensive indiscriminate use of alcohol-based hand sanitizers (ABHS), abuse, misuse, overdose of prescription drugs like chloroquine, hydroxychloroquine and chloroquine phosphate globally. While some preventive measures are recommended and adopted, such as national lockdown, self-isolation, quarantine, stay-at-home model, avoidance of large gathering, social distancing, wearing of face-masks and hand gloves, periodic hand washing particularly with liquid soaps/detergents under running tap water, avoidance of touching the face among others, the use of ABHS has been more prominent. ABHS contains on average 60-70 % by weight of one or more alcohols. During the 2019/2020 COVID-19 pandemic, the use of ABHS was more renowned to the extent that some individuals recommended the application on the hands every 30 minutes for a period of at least 20 seconds while outside the home. Though, the periodic application of the hand sanitizers seems like an effective on-the-go solution to preventing the spread of the virus, many other associated hazards call for caution. Besides transdermal absorption leading to mortality and morbidity of varying degree; alcohol-alcohol adulteration, deliberate and unintentional ingestion of ABHS may result in respiratory depression, irreversible blindness, intoxication, cirrhosis, acidosis, headache, central nervous system depression, seizure, hypoglycemia, coma, or even death in some cases. The non-ABHS are equally not absolutely safe as many of them contain active agents that are allegedly carcinogenic, toxic, inducing microbial resistance and endocrine disruption. Considered together, this implies that while some may not die from contracting the disease, the preventive measures taken could lead to death or other forms of morbidity thereby revealing that there is indeed, death in preventive measures when done without cautionary measures. This study seeks to highlight some associated risks in the use of ABHS and non-ABHS, whilst advocating the use of safer or ‘greener’ alternative procedure for use as preventive measures particularly during the COVID-19 pandemic

The Screening of Phytoconstituents, Antibacterial and Antifungal Activities of Brysocarpus Coccineus Schum and Thonn. Stem (Connaraceae)

ABSTRACT The uses of Brysocarpus coccineus stem in traditional African medicine have led to the antibacterial and antifungal activities of the hexane, ethylacetate and methanol stem extracts of the plant evaluation using six pathogenic bacteria and six fungi. The extracts inhibited the 12 test organisms to different degrees. Hexane, ethylacetate and methanol successive extracts of Brysocarpus coccineus stem effectively inhibited the growth of Escherichia coli, Bacillus subtilis and Pseudomonas aeruginosa at concentrations between 12.5 and 200mg/ml, while the extracts showed lower inhibition on Staphylococcus aureus, Salmonellae typhii and Klebsiellae pneumonae. The sensitivity of test bacteria was concentration dependent, activity being higher at higher concentrations of the three extracts. Ethylacetate and methanol exhibited higher antifungal properties on Rhizopus stolon and Epidermophyton floccosum, while hexane also inhibited the growth of Rhizopus stolon, Epidermophyton floccosum, Tricophyton rubrum and Aspergillus niger with activity comparable to that of the reference drug tioconazole. Preliminary phytochemical screening of the three extracts revealed the presence of saponins, reducing sugar, steroids, glycosides, flavonoids and anthraquinones

Isolation and antiproliferative activity of triterpenoids and fatty acids from the leaves and stem of <i>Turraea vogelii</i> Hook. f. ex benth

<p>Chloroform extract from the leaves of <i>Turraea vogelii</i> Hook f. ex Benth demonstrated cytotoxic activity against a chronic myelogenous leukemia cell, K-562 with IC₅₀ of 14.27 μg/mL, while chloroform, ethyl acetate and methanol extracts from the stem of the plant inhibited K-562 cells growth with IC₅₀ of 19.50, 24.10 and 85.40 μg/mL respectively. Bioactive chloroform extract of <i>Turraea vogelii</i> leaves affords two triterpenoids: oleana-12,15,20-trien-3β-ol <b>(1)</b>, and oleana-11,13-dien-3β,16α,28-triol <b>(2)</b>, with six fatty esters, ethyl hexaeicos-5-enoate <b>(3)</b>, 3-hydroxy-1,2,3-propanetriyltris(tetadecanoate) <b>(4)</b>, 1,2,3-propanetriyl(7Z,7′Z,7′′Z)tris(-7-hexadecenoate) <b>(5)</b>, 1,2,3-propanetriyl(5Z,5′Z,5′′Z)tris(-5-hexadecenoate) <b>(6)</b>, 1,2,3-propanetriyltris(octadecanoate) <b>(7)</b>, and 2β-hydroxymethyl tetraeicosanoate <b>(8).</b> Tetradecane (<b>9)</b>, four fatty acids: hexadecanoic acid (<b>10)</b>, tetradecanoic acid (<b>11)</b>, <b><i>(</i></b><i>Z)</i>-9-eicosenoic acid <b>(12)</b>, and ethyl tetradec-7-enoate <b>(13)</b> were isolated from chloroform extract of <i>Turraea vogelii</i> stem. 1,2,3-propanetriyltris(heptadecanoate) <b>(14)</b>, <i>(Z)</i>-9-octadecenoic acid <b>(15)</b> and <i>(Z)</i>-7-tetradecenoic acid <b>(16)</b> were isolated from ethyl acetate extract while <i>(Z)</i>-5-pentadecenoic acid <b>(17)</b> was obtained from methanol extract of the plant stem. Compounds <b>1</b>, <b>2</b>, <b>5</b>, <b>6</b>, <b>11</b>, <b>12</b>, <b>15</b>, <b>16</b> and <b>17</b> exhibited pronounced antiproliferative activity against K-562 cell lines.</p

Thigh-length compression stockings and DVT after stroke

Controversy exists as to whether neoadjuvant chemotherapy improves survival in patients with invasive bladder cancer, despite randomised controlled trials of more than 3000 patients. We undertook a systematic review and meta-analysis to assess the effect of such treatment on survival in patients with this disease

Azithromycin in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Background Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatory actions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19. Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospital with COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients were randomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once per day by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatment groups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment and were twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants and local study staff were not masked to the allocated treatment, but all others involved in the trial were masked to the outcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) were eligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was 65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomly allocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall, 561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days (rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median 10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days (rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, no significant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24). Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or other prespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restricted to patients in whom there is a clear antimicrobial indication. Funding UK Research and Innovation (Medical Research Council) and National Institute of Health Research