Synthesis of N-substituted acetamide derivatives of azinane-bearing 1,3,4-oxadiazole nucleus and screening for antibacterial activity

Purpose: To synthesize some acetamide derivatives bearing azinane and 1,3,4-oxadiazole heterocyclic cores and to evaluate their antibacterial potentials.Methods: Ethyl piperidin-4-carboxylate (2) was converted to ethyl 1-[(4-chlorophenyl)sulfonyl]piperidin- 4-carboxylate (3), 1-[(4-chlorophenyl)sulfonyl]piperidin-4-carbohydrazide (4) and 5-[1-(4-chlorophenylsulfonyl)-4-piperidinyl]-1,3,4-oxadiazol-2-thiol (5) using three consecutive steps. The target molecules, 5-{1-[(4-chlorophenyl)sulfonyl]piperidin-4-yl}-2-{[N-(substituted)-2-acetamoyl]thio]}-1,3,4- oxadiazole (8a-n) were synthesized by stirring 5 and N-aryl-2-bromoacetamides (7a-n) in an aprotic polar solvent. The structures were corroborated by infrared (IR), electron impact mass spectrometry (EIMS) and proton/carbon nuclear magnetic resonance (1H/13C-NMR) spectroscopic techniques. The evaluation of antibacterial activity was based on the effect on the increase in absorbance of the broth medium due to log phase microbial growth.Results: Compound 8g bearing a 2-methylphenyl group was the most the active growth inhibitor of Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis bacterial strains with minimum  inhibitory concentrations (MIC) of 10.63±0.97, 10.31±1.00, 10.45 ± 0.94 and 11.77±5.00 μM, respectively. Ciprofloxacin was used as reference standard.Conclusion: All the synthesized compounds are moderate inhibitors but relatively more active against Gram-negative bacterial strains. 5-{1-[(4- Chlorophenyl)sulfonyl]piperidin-4-yl}-2-{[N-(2-methylphenyl)-2- acetamoyl]thio]}-1,3,4-oxadiazole (8g) is the most active growth inhibitor of all the strains except Staphylococcus aureus.Keywords: 1,3,4-Oxadiazole, Acetamides, Antibacterial activity, Piperidin

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population.The aim of this study was to inform vaccination prioritization by modelling the impact of vaccination on elective inpatient surgery. The study found that patients aged at least 70 years needing elective surgery should be prioritized alongside other high-risk groups during early vaccination programmes. Once vaccines are rolled out to younger populations, prioritizing surgical patients is advantageous