Синтез, протимікробна активність та докінгові дослідження 6-(1H-бензімідазол-2- іл)-5-метилтієно[2,3-d]піримідин-4(3H)-онів з ацетамідними та 1,2,4-оксадіазол-5- ілметильними замісниками

Aim. To synthesize, study the antimicrobial activity and suggest antimicrobial activity mechanism for the novel derivatives of 6-(1H-benzimidazol-2-yl)-5-methylthieno[2,3-d]pyrimidin-4(3H)-one. Results and discussion. As the result of the targeted modification of 6-(1H-benzimidazol-2-yl)-5-methylthieno[2,3-d]-pyrimidin-4(3H)-one in position 3 with acetamide and 1,2,4-oxadiazol-5-ylmethyl substituents, the compounds, which demonstrated better antimicrobial activity in the agar well diffusion assay than the reference drug Streptomycin, were obtained. To elucidate the mechanism of action of the novel compounds, the docking studies were con-ducted to the active site of the 16S subunit of ribosomal RNA, the proven target for aminoglycoside antibiotics, as well as tRNA (Guanine37-N1)-methyltransferase (TrmD), which inhibitors were considered as a new potential class of antibiotics. Experimental part. By the interaction of 6-(1H-benzimidazol-2-yl)-5-methylthieno[2,3-d]pyrimidin-4(3H)-one with a series of N-arylchloroacetamides and 3-aryl-5-(chloromethyl)-1,2,4-oxadiazoles in DMF in the presence of K2CO3 the target compounds were obtained. The antimicrobial activity was assessed by the agar well diffusion method. The concentration of microbial cells was determined by the McFarland standard; the value was 107 cells in 1 mL of the media. The 18 – 24 hour culture of microorganisms was used for tests. For the bacteria cultivation, Müller-Hinton agar was used, Sabouraud agar was applied for C. albicans cultivation. The compounds were tested as the DMSO solution with the concentration of 100 µg/mL; the volume of the solution was 0.3 mL, the same volume was used for Streptomycin (the concentration 30 µg/mL). The docking studies were performed using Autodock Vina. Crystallographic data for the complexes of Streptomycin with the 16S subunit of ribosomal RNA (1NTB) and its active site, as well as for tRNA (Guanine37-N1)-methyltransferase (EC 2.1.1.228; TrmD) (5ZHN) and its active site were obtained from the Protein Data Bank.Conclusions. It has been determined that 2-[6-(1H-benzimidazol-2-yl)-5-methyl-4-oxothieno[2,3-d]pyrimidin-3(4H)-yl]-N-[4-(ethoxy)phenyl]acetamide, which is the most active as an antimicrobial agent among the compounds tested, also shows the best binding activity towards the active site of tRNA (guanine37-N1)-methyltransferase.Мета. Синтезувати й дослідити протимікробну активність нових похідних 6-(1H-бензімідазол-2-іл)-5-метилтієно[2,3-d]піримідин-4(3H)-онів та запропонувати механізм протимікробної активності.Результати та їх обговорення. У результаті цілеспрямованої модифікації положення 3 6-(1H-бензімідазол-2-іл)-5-метилтієно[2,3-d]піримідин-4(3H)-ону ацетамідним та 1,2,4-оксадіазол-5-ілметильним замісниками було одержано сполуки з визначеною методом дифузії в агар протимікробною активністю, що є більшою за активність препарату порівняння Стрептоміцину. З метою з’ясування механізму дії синтезованих сполук було проведено докінгові дослідження щодо активного сайту субодиниці 16S рибосомальної РНК, яка є підтвердженою мішенню для аміноглікозидних антибіотиків, а також тРНК (Гуанін-37-N1)-метилтрансферази (TrmD), інгібітори якої розглядаються як новий потенційний клас антибіотиків. Експериментальна частина. Шляхом взаємодії 6-(1H-бензімідазол-2-іл)-5-метилтієно[2,3-d]піримідин-4(3H)-ону з рядом N-арилхлороацетамідів та 3-арил-5-(хлорометил)-1,2,4-оксадіазолів в умовах ДМФА-K2CO3 було одержано цільові сполуки. Антимікробну активність визначали методом дифузії в агар. Концентрацію мікробних клітин визначали за МакФарландом; мікробне навантаження склало 107 мікробних одиниць в 1 мл середовища. Для тестів використовували 18 – 24 годинну культуру мікроорганізмів. Для культивування бактерій використовували агар Мюллера-Гінтона; для культивування C. albicans використовували агар Сабуро. Сполуки вводили методом дифузії в агар (лунками) у вигляді розчину у ДМСО в концентрації 100 мкг/мл в об’ємі 0,3 мл; аналогічний об’єм використовували для Стрептоміцину (конц. 30 мкг/мл). Докінгові дослідження проводили за допомогою програми Autodock Vina. Кристалографічні дані для комплексів стрептоміцину з 16S субодиницею рибосомальної РНК (1NTB) та її активного сайту і для тРНК (Гуанін-37-N1)-метилтрансферази (EC 2.1.1.228; TrmD) (5ZHN) та її активного сайту було отримано з Protein Data Bank.Висновки. Виявлено, що сполука 2-[6-(1H-бензімідазол-2-іл)-5-метил-4-оксотієно[2,3-d]піримідин-3(4H)-іл]-N-[4-(етокси)феніл]ацетамід, яка характеризується найбільшою протимікробною активністю, у докінгових розрахунках є також найбільш ефективним інгібітором тРНК (Гуанін-37-N1)-метилтрансферази

Effect of 4% Albumin Solution vs Ringer Acetate on Major Adverse Events in Patients Undergoing Cardiac Surgery With Cardiopulmonary Bypass A Randomized Clinical Trial

IMPORTANCE In cardiac surgery, albumin solution may maintain hemodynamics better than crystalloids and reduce the decrease in platelet count and excessive fluid balance, but randomized trials are needed to compare the effectiveness of these approaches in reducing surgical complications. OBJECTIVE To assess whether 4% albumin solution compared with Ringer acetate as cardiopulmonary bypass prime and perioperative intravenous volume replacement solution reduces the incidence of major perioperative and postoperative complications in patients undergoing cardiac surgery. DESIGN, SETTING, AND PARTICIPANTS A randomized, double-blind, single-center clinical trial in a tertiary university hospital during 2017-2020 with 90-day follow-up postoperatively involving patients undergoing on-pump coronary artery bypass grafting; aortic, mitral, or tricuspid valve surgery; ascending aorta surgery without hypothermic circulatory arrest; and/or the maze procedure were randomly assigned to 2 study groups (last follow-up was April 13, 2020). INTERVENTIONS The patients received in a 1:1 ratio either 4% albumin solution (n = 693) or Ringer acetate solution (n = 693) as cardiopulmonary bypass priming and intravenous volume replacement intraoperatively and up to 24 hours postoperatively. MAIN OUTCOMES AND MEASURES The primary outcomewas the number of patients with at least 1 major adverse event: death, myocardial injury, acute heart failure, resternotomy, stroke, arrhythmia, bleeding, infection, or acute kidney injury. RESULTS Among 1407 patients randomized, 1386 (99%; mean age, 65.4 [SD, 9.9] years; 1091 men [79%]; 295 women [21%]) completed the trial. Patients received a median of 2150 mL (IQR, 1598-2700 mL) of study fluid in the albumin group and 3298 mL (IQR, 2669-3500 mL) in the Ringer group. The number of patients with at least 1 major adverse event was 257 of 693 patients (37.1%) in the albumin group and 234 of 693 patients (33.8%) in the Ringer group (relative risk albumin/Ringer, 1.10; 95% CI, 0.95-1.27; P =.20), an absolute difference of 3.3 percentage points (95% CI, -1.7 to 8.4). The most common serious adverse events were pulmonary embolus (11 [1.6%] in the albumin group vs 8 [1.2%] in the Ringer group), postpericardiotomy syndrome (9 [1.3%] in both groups), and pleural effusion with intensive care unit or hospital readmission (7 [1.0%] in the albumin group vs 9 [1.3%] in the Ringer group). CONCLUSIONS AND RELEVANCE Among patients undergoing cardiac surgery with cardiopulmonary bypass, treatment with 4% albumin solution for priming and perioperative intravenous volume replacement solution compared with Ringer acetate did not significantly reduce the risk of major adverse events over the following 90 days. These findings do not support the use of 4% albumin solution in this setting.Peer reviewe

Effect and safety of 4% albumin in the treatment of cardiac surgery patients : study protocol for the randomized, double-blind, clinical ALBICS (ALBumin In Cardiac Surgery) trial

Background In cardiac surgery with cardiopulmonary bypass (CPB), large amounts of fluids are administered. CPB priming with crystalloid solution causes marked hemodilution and fluid extravasation. Colloid solutions may reduce fluid overload because they have a better volume expansion effect than crystalloids. The European Medicines Agency does not recommend the use of hydroxyethyl starch solutions (HES) due to harmful renal effects. Albumin solution does not impair blood coagulation but the findings on kidney function are conflicting. On the other hand, albumin may reduce endothelial glycocalyx destruction and decrease platelet count during CPB. No large randomized, double-blind, clinical trials have compared albumin solution to crystalloid solution in cardiac surgery. Methods/design In this single-center, double-blind, randomized controlled trial comprising 1386 adult cardiac surgery patients, 4% albumin solution will be compared to Ringer's acetate solution in CPB priming and volume replacement up to 3200 mL during surgery and the first 24 h of intensive care unit stay. The primary efficacy outcome is the number of patients with at least one major adverse event (MAE) during 90 postoperative days (all-cause death, acute myocardial injury, acute heart failure or low output syndrome, resternotomy, stroke, major arrhythmia, major bleeding, infection compromising post-procedural rehabilitation, acute kidney injury). Secondary outcomes are total number of MAEs, incidence of major adverse cardiac events (MACE; cardiac death, acute myocardial injury, acute heart failure, arrhythmia), amount of each type of blood product transfused (red blood cells, fresh frozen plasma, platelets), total fluid balance at the end of the intervention period, total measured blood loss, development of acute kidney injury, days alive without mechanical ventilation in 90 days, days alive outside intensive care unit at 90 days, days alive at home at 90 days, and 90-day mortality. Discussion The findings of this study will provide new evidence regarding efficacy and safety of albumin solution in adult patients undergoing cardiac surgery with CPB.Peer reviewe

Measurement of inclusive (D-s(+/-)) photoproduction at HERA

The first measurement of inclusive D-s(+/-) photoproduction at HERA has been performed with the ZEUS detector for photon-proton centre-of-mass energies; 130 DsX) = 3.79 +/- 0.59(stat.)(-0.46)(+0.26)(syst.) +/- 0.94(br.) nb, where the last error arises from the uncertainty in the D-s(+/-) decay branching ratio. The measurements are compared with inclusive D*(+/-) photoproduction cross sections in the same kinematic region and with QCD calculations. The D-s(+/-) cross sections lie above a fixed-order next-to-leading order calculation and agree better with a tree-level O(alpha alpha(s)(3)) calculation that was tuned to describe the ZEUS D* (+/-) cross sections. The ratio of D-s(+/-) to D*(+/-) cross sections is 0.41 +/- 0.07(stat.)(-0.05)(+0.03)(syst.) +/- 0.10 (br.). From this ratio, the strangeness-suppression factor in charm photoproduction, within the LUND string fragmentation model, has been calculated to be gamma(s)= 0.27 +/- 0.05 +/- 0.07(br.). The cross-section ratio and gamma(s) are in good agreement with those obtained in charm production in e(+)e(-) annihilation. (C) 2000 Elsevier Science B.V. All rights reserved

Synthesis, in silico and in vitro antimicrobial activity of N-(benzyl)-5-methyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine-6-carboxamides

According to the recent studies bezylcarboxamide fragment attached to the thiophene ring of thieno[2,3-d]pyrimidine is beneficial for antimicrobial activity of the compounds. Therefore we focused our efforts on constructing of the simple molecules such as N-(benzyl)-5-methyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine-6-carboxamides to get deeper insight into their antimicrobial activity. As the optimal procedure for preparation of target compounds we choose 1,1’-carbonyldiimidazole promoted interaction of 5-methyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine-6-carboxylic acid with the series of substituted benzyl amines. The obtained amides showed good activity against the strains of S. aureus and B. subtilis, which was higher for the derivative without substituents in benzene ring or the compounds with small substituents like methyl or methoxyl groups in the para-position of the benzene ring. Docking studies showed that despite the good values of the scoring functions, the conformational analysis of the ligands’ poses in the active site revealed their ability for only partial inhibition of TrmD of P. aeruginosa

Synthesis, in silico and in vitro antimicrobial activity of N-(benzyl)-5-methyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine-6-carboxamides

According to the recent studies bezylcarboxamide fragment attached to the thiophene ring of thieno[2,3-d]pyrimidine is beneficial for antimicrobial activity of the compounds. Therefore we focused our efforts on constructing of the simple molecules such as N-(benzyl)-5-methyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine-6-carboxamides to get deeper insight into their antimicrobial activity. As the optimal procedure for preparation of target compounds we choose 1,1’-carbonyldiimidazole promoted interaction of 5-methyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine-6-carboxylic acid with the series of substituted benzyl amines. The obtained amides showed good activity against the strains of S. aureus and B. subtilis, which was higher for the derivative without substituents in benzene ring or the compounds with small substituents like methyl or methoxyl groups in the para-position of the benzene ring. Docking studies showed that despite the good values of the scoring functions, the conformational analysis of the ligands’ poses in the active site revealed their ability for only partial inhibition of TrmD of P. aeruginosa

Synthesis and Antimicrobial Evaluation of 2-(6-Imidazo[1,2-a]pyridin-2-yl-5-methyl-2,4-dioxo-3-phenyl-3,4-dihydrothieno[2,3-d]pyrimidin-1(2H)-yl)-N-arylacetamide Derivatives

6-Heteryl-5-methylthieno[2,3-d]pyrimidin-2,4(1H,3H)-diones are of great interest as the promising objects for the search of antibacterials. In this communication, we obtained 6-(imidazo[1,2-a]pyridin-2-yl)-5-methyl-3-phenylthieno[2,3-d]pyrimidine-2,4(1H,3H)-dione by interaction of 6-(bromoacetyl)-5-methyl-3-phenylthieno[2,3-d]pyrimidine-2,4(1H,3H)-dione with 2-aminopyridine. The obtained heterocyclic hybrid was further modified by alkylation with 2-chloroarylacetamides. Antimicrobial activity studies for the synthesized compounds using the agar well diffusion method revealed their moderate activity against S. aureus, E. coli and B. subtilis. According to the double dilution assay MIC value results for 6-(imidazo[1,2-a]pyridin-2-yl)-5-methyl-3-phenylthieno[2,3-d]pyrimidine-2,4(1H,3H)-dioneagainst P. aeruginosa was less than the value determined for the reference drug streptomycin. The docking study of the synthesized compounds to the active site of TrmD isolated from P. aeruginosa did not show their effective inhibitory activity