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The Suzuki-Miyaura cross-coupling (SMCC) involves the coupling of organohalides and organoboron molecules in the presence of Pd(II)-based catalysts. Often SMCC reactions employ homogenous catalysts. However, such homogenous SMCC reactions are associated with certain limitations which has motivated design of effective and sustainable Pd(II)-based heterogeneous catalytic systems. Herein, we report a systematic development of a Pd(II)-immobilized and triptycene based ionic hyper crosslinked polymer (Pd@TP-iHCP) and explored its application as a heterogeneous catalyst for SMCC reaction. Pd@TP-iHCP has ample N-heterocyclic carbene (NHC) pendants that anchor Pd(II) centres on the polymeric matrix. Pd@TP-iHCP was characterized satisfactorily using FT-IR, 13 C CP-MAS NMR, BET surface area analysis, SEM, EDX and HRTEM. The performance of Pd@TP-iHCP as a heterogeneous catalyst for SMCC reactions was explored using various combinations of aryl boronic acids and aryl halides. Experimental results show that Pd@TP-iHCP is associated with a moderately high surface area. It is an efficient catalyst for SMCC (in aqueous media) with a modest loading of 0.8â mol % Pd(II)-catalyst since high yields of the expected products were obtained in shorter time intervals. Pd@TP-iHCP also features excellent stability and catalyst recyclability since it could be re-used for several cycles without any significant decrease in catalytic efficiency.
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We used the data collection experience of the initial 3 years of Samrakshan to develop a live dashboard for individual practitioners to examine diagnostic and performance metrics in real-time and to assess trends. The dashboard was created in MS Excel (Microsoft 365 MSO version 2209) and the output provides useful information on actionable items like compliance with low-dose aspirin and estimates of preterm and term pre-eclampsia and fetal growth restriction, congenital anomalies, the proportion of preterm births, and perinatal mortality estimates. The output will help individual practitioners to generate practice-related actionable evidence and can further optimize service delivery for local populations. The dashboard can be used on any platform with MS Excel and does not require the installation of any additional software or license. The dashboard is provided as a free, open-access resource by the Samrakshan Program of Indian Radiological and Imaging Association.
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Functionalized aryl(heteroaryl) ketones are present in many natural products as key structural components and serve as basic synthetic building blocks for various organic transformation reactions. Therefore, the development of an effective and sustainable route for making these classes of compounds remains challenging yet highly desirable. Herein, we report a simple and efficient catalytic system for dialkynylation of aromatic/heteroaromatic ketones via a double C-H bond activation in the presence of less expensive ruthenium(II)-salt as a catalyst using the weakly and native carbonyl group as the desired directing group. The developed protocol is highly compatible, tolerant, and sustainable toward various functional groups. The synthetic utility of the developed protocol has been demonstrated through the scale-up synthesis and functional group transformation. Control experiments support the involvement of the base-assisted internal electrophilic substitution (BIES) reaction pathway.
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Cetonas , Rutenio , Cetonas/química , Catálisis , Rutenio/químicaRESUMEN
Aim The aim of this study was to determine the changes in the mean arterial blood pressure (MAP) and mean uterine artery (UtA) pulsatility index (PI) from 11-14 to 19-24 + 6 gestation weeks in Asian Indian pregnant women. Methods Clinical and demographic details, MAP, and mean UtA PI measures were ascertained for pregnant women at 11 to 14 gestation weeks and 19-24 + 6 gestation weeks. Women were categorized as a high-or-low risk for preterm preeclampsia using the Fetal Medicine Foundation algorithm and 1 in 150 cutoff. High-risk pregnant women were recommended low-dose aspirin 150 mg daily at bedtime. Changes in MAP and mean UtA PI were compared for gestational age intervals and high-and-low risk women using nonparametric tests. Results The study analyzed the results of 1,163 pregnant women. Both MAP (mean difference: 5.14, p < 0.001) and mean UtA PI (mean difference: 0.14, p < 0.001) remained significantly higher at the second-trimester assessment in high-risk pregnant women compared to low-risk pregnant women. Seventy-seven (35.16%) of the 219 pregnant women with abnormal mean UtA PI in the first trimester had an abnormal mean UtA PI in the second-trimester assessment. One hundred (10.59%) of the 944 pregnant women with normal mean UtA PI in the first trimester had an abnormal mean UtA PI in the 19-24 + 6 weeks assessment. Seventy-seven pregnant women (6.62% of 1,163 women, 95% confidence interval: 5.33, 8.20) had an abnormal mean UtA PI at both gestation age intervals. High-risk pregnant women taking low-dose aspirin daily showed a larger reduction in mean UtA PI compared to high-risk pregnant women that did not report the use of low-dose aspirin (0.89 vs. 0.62, p <0.001) Conclusion MAP and mean UtA PI decreased significantly from the first to the second trimester of pregnancy. Sequential assessment of the MAP and mean UtA PI in the first and second trimesters of pregnancy will be useful for fetal radiologists in India to identify a subgroup of women with abnormal mean UtA PI at both trimesters that may need more intense surveillance and follow-up till childbirth.
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Aim To determine the diagnostic effectiveness of third-trimester fetal Doppler studies in pregnancy for stillbirths and neonatal mortality in the Samrakshan program of the Indian Radiological and Imaging Association (IRIA). Methods The mean uterine artery (UtA) pulsatility index (PI) > 95th percentile, umbilical artery PI > 95th percentile, middle cerebral artery (MCA) PI < 5th percentile, and/or cerebroplacental ratio (CPR) < 5th percentile in the third trimester fetal Doppler study was considered as abnormal. The results of the fetal Doppler study closest to childbirth were considered for analysis. Late stillbirth (SB) was defined as a fetal loss between 28 and 36 gestation weeks and the term SB was defined as a fetal loss at ≥ 37 gestation weeks. Neonatal death was defined as the demise of a live-born baby within the first 28 days of life. Parameters of diagnostic effectiveness such as sensitivity, specificity, positive and negative predictive values and likelihood ratios, diagnostic odds ratio, and the area under receiver operator characteristic (AUROC) curve were assessed. Results Screening of 1,326 pregnant women in the third trimester of pregnancy between September 2019 and February 2022, identified 308 (23.23%) abnormal Doppler studies, 11 (0.83%) SB, and 11 (0.84%) neonatal deaths. An abnormal Doppler study was significantly associated with late stillbirths (OR 37.2, 95% CI: 2.05, 674) but not with term SB (OR: 3.38, 95% CI: 0.76, 15) or neonatal deaths (OR 1.39, 95% CI: 0.40, 4.87). Mean UtA PI, umbilical artery PI, MCA PI, and CPR were significantly associated with late SB and not term SB. The AUROC of Doppler measures was excellent for late SB but did not show discriminatory ability for term SB or neonatal deaths. Conclusion Integration of fetal Doppler with routine third-trimester antenatal scans can help identify pregnant women at high risk for late SB. The effectiveness of fetal Doppler to identify pregnant women at high risk for term SB and neonatal deaths needs further study on a larger sample size.
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Aim To determine the effectiveness of the first trimester Samrakshan protocol for the identification of pregnant women at high risk for preterm pre-eclampsia (PE). Methods Samrakshan uses a protocol that integrates routine first-trimester ultrasound assessment at 11 to 14 gestation weeks with the measurement of mean arterial blood pressure and mean uterine artery pulsatility index assessment to determine a customized risk for preterm PE and fetal growth restriction. Based on the risk assessment, pregnant women are classified as high or low risk. Results The protocol had a high specificity (90.4%, 95% CI: 89.4%, 91.2%) and negative predictive value (98.1%, 95% CI: 97.6%, 99%) for preterm PE. The odds ratio and positive likelihood ratio for preterm PE were 16.7 (95% CI: 12.3, 22.6) and 6.64 (95% CI: 5.77, 7.63), respectively. Conclusions The positive likelihood ratio and odds ratios indicate that pregnant women identified as high risk for preterm PE using the first-trimester protocol of Samrakshan are significantly more likely to develop preterm PE than low-risk women.
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Aim To compare the magnitude of fetuses with congenital anomalies, pregnant women identified at high risk for preterm pre-eclampsia (PE) or with preterm PE, and with early fetal growth restriction (FGR) or high risk for FGR at the second trimester assessment at 20 to 24 weeks of gestation. Methods A standardized trimester-specific protocol that included clinical and demographic details, fetal biometry, estimated fetal weight (EFW), fetal abdominal circumference (FAC), mean arterial blood pressure and fetal Doppler studies was used to identify high risk for preterm PE and FGR. The Targeted Imaging for Fetal Anomalies (TIFFA) scan was used to identify congenital anomalies. In addition, 95% confidence intervals of the point estimates were derived, and the p -value was estimated to assess the statistical significance of the difference in proportions. Results Analysis of the data of 4,572 pregnant women screened between 20 and 24 gestation weeks showed a significantly lower prevalence ( p < 0.001) of congenital abnormalities (3.81%) compared to women diagnosed with early PE (2.71%) or with a high risk for PE (4.00%) and women (6.80%) with early FGR or at higher risk for fetal growth restriction with both EFW and FAC < 10th percentile. Conclusion The data on prevalence from Samrakshan show that the second-trimester assessment of pregnant women in India must expand its scope from the TIFFA scan to also focus on screening to identify women at high risk for preterm PE and FGR.
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Aim To determine the trends in preterm birth (PTB) rates in Samrakshan after initiating a third-trimester screening protocol. Methods The Samrakshan program of IRIA focused on clinical stage-based management of fetal growth restriction (FGR) in the third trimester integrating fetal Doppler studies with routine trimester-specific antenatal scans. Mean uterine artery pulsatility index (PI), umbilical artery PI, middle cerebral artery PI, and cerebroplacental ratio were assessed for all third-trimester pregnant women in the program. Results From 2019 to 2022, 249 (18.33%, 95% CI: 16.34, 20.54) women had PTB with 221 (16.67%, 95% CI: 14.73, 18.75) PTBs between 34 and 37 gestation weeks and 22 (1.66%, 95% CI: 1.10, 2.50) PTBs at gestation < 34 weeks. The overall preterm birth rates showed a significant (chi-square p < 0.001) declining trend each year from 23.18% ( n = 121) in 2019-2020 to 16.81% ( n = 99) in 2020-2021 and 10.75% ( n = 23) in 2021-2022. Conclusion The declining trend of PTB rates in the Samrakshan program shows that the reduction of PTB is an added benefit of the integration of fetal Doppler studies in the third trimester of pregnancy.
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Herein, we report ruthenium(II)-catalyzed weakly coordinating primary amide-assisted ortho-di-alkynylation of (hetero)arylamides via double C-H bond activation in the presence of bromo-alkynes as coupling partners. The attractive features of the developed strategy lie in the usage of an inexpensive ruthenium(II)-salt, external auxiliary-free directing group and simple reaction conditions, along with a broad substrate scope, high reaction yields and scale-up synthesis.
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Rutenio , Alquinos/química , Amidas/química , Catálisis , Rutenio/químicaRESUMEN
Aim The aim of the study is to determine improvements in perinatal mortality at the end of the first 2 years from the initiation of the Samrakshan program of the Indian Radiological and Imaging Association. Methods Samrakshan is a screening program of pregnant women that uses trimester-specific risk assessment protocols including maternal demographics, mean arterial pressure, and fetal Doppler studies to classify women as high risk or low risk for preterm preeclampsia (PE) and fetal growth restriction (FGR). Low dose aspirin 150 mg daily once at bedtime was started for pregnant women identified as high risk in the 11-13 6/7 weeks screening. The third-trimester screening focused on the staging of FGR and protocol-based management for childbirth and risk assessment for PE. Outcomes of childbirth including gestational age at delivery, development of PE, and perinatal mortality outcomes were collected. Results Radiologists from 38 districts of 16 states of India participated in the Samrakshan program that screened 2,816 first trimester, 3,267 second trimester, and 3,272 third trimester pregnant women, respectively. At 2 years, preterm PE was identified in 2.76%, preterm births in 19.28%, abnormal Doppler study in 25.76% of third trimester pregnancies, and 75.32% of stage 1 FGR delivered at term. The neonatal mortality rate was 9.86/1,000 live births, perinatal mortality rate was 18.97/1,000 childbirths, and maternal mortality was 58/100,000 live births compared with 29.5, 36, and 113, respectively in 2016. Conclusion Fetal Doppler integrated antenatal ultrasound studies in Samrakshan led to a significant reduction in preterm PE rates, preterm birth rates, and a significant improvement in mean birth weights. Perinatal, neonatal, and maternal mortality rates are significantly better than the targets for 2030 set by the Sustainable Development Goals-3.
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Ru(II)-catalyzed regioselective ortho-alkenylation of primary benzamides with activated olefins has been realized over the competitive cyclized products. This reaction overall proceeds via a cross-dehydrogenative coupling (CDC) reaction using a simple and weakly coordinating primary amide group in the presence of an inexpensive Ru(II) salt and allows the controlled introduction of olefin motifs at the ortho-position of benzamides. The key to the success of this strategy depends on fine-tuning the reaction conditions. The developed protocol has demonstrated excellent regio/diastereoselectivity and a good functional group tolerance with wide substrate scope and obviates the requirement of external auxiliaries as well as the costly metal catalyst. Detailed mechanistic studies indicate the involvement of the base-assisted internal electrophilic-type substitution (BIES) step in the reaction mechanism.
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An expeditious approach has been developed for the synthesis of succinimide-fused unsymmetrical 9,10-dihydrophenanthrenes from simple aryl iodides and maleimides. The developed transformation, overall proceeding with high regioselectivity via a cascade approach through palladium(II)-catalyzed Micheal-type addition/C-H activation/intramolecular cross-dehydrogenative coupling (ICDC)/C-H activation, allows formation of four fundamental carbon-carbon bonds in one-pot fashion. The reactions tolerate broad functional groups and satisfy the parameters of atom and step economy. Detailed mechanistic studies were carried out to support the proposed synthetic pathway.