Substantial Intensification of the Quantum Yield of Samarium(III) Complexes by Mixing Ligands: Microwave-Assisted Synthesis and Luminescence Properties.

A luminescence quantum yield of 7.8% was obtained for a quaternary mixed-ligand samarium complex; this value is higher than those previously reported in the literature for such complexes in solution. The complex was prepared by microwave-assisted synthesis in 15 min with a yield of 69%; that is, ∼400 times faster than the usual synthesis that required 4 days and led to a yield of only 30%. Therefore, we propose microwave-assisted synthesis as the method of choice for preparing mixed-ligand lanthanoid complexes.

Effectiveness to identify acute myocardial infarction using the Manchester screening in patients with chest pain at the emergency service.

BACKGROUND: Among cardiovascular diseases (CVD), acute coronary syndrome (ACS) is the main manifestation, corresponding to signs and symptoms that occur with ischemia and outcome of angina or acute myocardial infarction (AMI). The aim of this study was to investigate the performance of biochemical markers eligible in a chest pain protocol, using Point of care Test (POCT), in patients in a reference emergency room. METHODS: In this study, 1380 medical records of patients of both genders were evaluated, ranked by applying chest pain protocol using the Manchester Triage System (MTS). Markers for myocardial injury were measured in serial analysis including myoglobin (Mgb), creatine kinase MB fraction mass (CK-MB), and cardiac troponin I (cTnI). RESULTS: Acute myocardial infarction was predominant in males (P < .001), in patients with hypertension (P < .001), and in those with previous myocardial infarction (P < .026) and significant electrocardiogram (ECG) data for AMI screening (P < .001). A multivariate regression model showed as predictors for AMI the variables ECG data by admittance at the emergency room, previous AMI history, levels of both Mgb at the third hour, and cTnI at the sixth hour after admission. CONCLUSION: This study showed the importance of a rapid and serial test as a cardiac marker for AMI screening, as well as has indicated the importance of time between the onset of chest pain and admission to the emergency room as an efficient aid in diagnosing this life-threatening disease.

Adaptation of gutta percha to oval canals: a cone beam computed tomographic analysis.

This study evaluated the influence of different instrumentation techniques on the adaptation of gutta percha cones in oval-shaped root canals. A total of 90 human single-rooted teeth were divided into groups according to the instrumentation technique that was used: group M, manual; group OM, hybrid: oscillatory plus manual; group PT, rotary (ProTaper Universal); group OPT, hybrid: oscillatory plus rotary (ProTaper Universal); group MT, rotary (Mtwo); and group OMT, hybrid: oscillatory plus rotary (Mtwo). After a single gutta percha cone was adapted to the canal, cone beam computed tomography was utilized to perform assessments at areas of greater contact of gutta percha to root canal walls. The adaptation was rated as ideal, satisfactory, minimally acceptable, or unsatisfactory. The frequency of ideal adaptation of the cone to the 4 canal walls varied from 26.67% (groups OMT and PT) to 73.33% (group MT); the differences between group MT and groups PT and OMT were statistically significant (P < 0.05). The mean area of the canal preparation without adaptation (contact) of the cone varied from 0.06 mm² (group MT) to 0.41 mm² (group OMT). The results showed that an instrumentation technique using the Mtwo system provided the best adaptation of the .04 gutta percha cones to anatomically oval root canals.

Persistent infection by Staphylococcus epidermidis in endodontic flare-up: a case report.

Endodontic flare-ups are challenging situations and may result from selective growth of specific bacterial species; microbial cultures and antibiograms should be used to allow faster, successful management of refractory lesions. A 47-year-old man reported pain on percussion after uncomplicated retreatment of the maxillary left canine for prosthetic purposes. In the following days, pain dramatically increased, leading to removal of the filling and use of intracanal medication. After many unsuccessful attempts to resolve the problem, a microbial culture of the root canal detected the presence of Staphylococcus epidermidis. An antibiogram determined the best drug combination to control this infection: tetracycline (oxytetracycline hydrochloride, 500 mg orally) plus third-generation cephalosporin (ceftriaxone, 1 g intramuscularly). Once the infection was controlled, the root canal was obturated. There was a reduction in the area of radiolucency, and the patient reported no pain at a 2-year follow-up.

Evaluation of Salt Intake, Urinary Sodium Excretion and Their Relationship to Overhydration in Chronic Kidney Disease Patients.

The purpose of this study was to estimate sodium intake in a group of patients with chronic kidney disease (CKD) and to correlate the results with the urinary excretion values of sodium and signs of fluid overload. We included patients with CKD in different stages. Urinary sodium was measured in 24 h urine samples. Body composition monitor (BCM) was used to estimate the hydration status. Sixty patients (38 ± 15 ml/min of GFR) presented 4.14 ± 1.71 g/24 h of urinary sodium excretion. Overhydration was detected in 50% of the patients by the BCM. There was a positive correlation between the measured sodium excretion values and BCM, ICW, ECW and TBW. In conclusion, markers of overhydration evaluated by BCM were positively correlated with urinary sodium excretion.

Exploring regional disparities in lung cancer mortality in a Brazilian state: A cross-sectional ecological study.

BACKGROUND: Lung cancer (LC) is one of the main causes of mortality in Brazil; geographic, cultural, socioeconomic and health access factors can affect the development of the disease. We explored the geospatial distribution of LC mortality, and associated factors, between 2015 and 2019, in Parana state, Brazil. METHODS AND FINDINGS: We obtained mortality (from the Brazilian Health Informatics Department) and population rates (from the Brazilian Institute of Geography and Statistics [IBGE]) in people over 40 years old, accessibility of oncology centers by municipality, disease diagnosis rate (from Brazilian Ministry of Health), the tobacco production rate (IBGE) and Parana Municipal Performance Index (IPDM) (from Parana Institute for Economic and Social Development). Global Moran's Index and Local Indicators of Spatial Association were performed to evaluate the spatial distribution of LC mortality in Parana state. Ordinary Least Squares Regression and Geographically Weighted Regression were used to verify spatial association between LC mortality and socioeconomic indicators and health service coverage. A strong spatial autocorrelation of LC mortality was observed, with the detection of a large cluster of high LC mortality in the South of Parana state. Spatial regression analysis showed that all independent variables analyzed were directly related to LC mortality by municipality in Paraná. CONCLUSIONS: There is a disparity in the LC mortality in Parana state, and inequality of socioeconomic and accessibility to health care services could be associated with it. Our findings may help health managers to intensify actions in regions with vulnerability in the detection and treatment of LC.

Lack of adequate predialyis care and previous hemodialysis, but not hemoglobin variability, are independent predictors of anemia-associated mortality in incident Brazilian peritoneal dialysis patients: results from the BRAZPD study.

BACKGROUND/AIMS: The objective of this study was to analyze the prevalence of anemia and variability of hemoglobin (Hb) values in peritoneal dialysis (PD) patients, to establish its associated factors and their impact on clinical outcomes in a large cohort of patients starting PD treatment. METHODS: Data were collected monthly in incident patients, who were followed until the primary endpoint (death from all causes) or until leaving the study. RESULTS: 2,156 patients starting PD were included. The prevalence of Hb lower than 11 g/dl was 57% at baseline and decreased to 38% at the 4th month. Lack of adequate predialysis care and previous treatment with hemodialysis were the most important factors associated with anemia. Anemia was an independent predictor of mortality. There were no differences in patient survival throughout the different groups of Hb variability. CONCLUSION: Our data point to the need of identifying other risk factors for anemia and aggressively interfere with the modifiable ones in order to correct anemia and decrease mortality in this group of high-risk patients.

A gut feeling on endotoxemia: causes and consequences in chronic kidney disease.

Chronic inflammation is closely linked to several complications of chronic kidney disease (CKD), such as vascular calcification, accelerated atherosclerosis, loss of appetite, insulin resistance, increased muscle catabolism and anemia. As a consequence, inflammation is a predictor of mortality in this group of patients. Specific causes of the activation of the immune system in CKD are largely unknown. Endotoxin (ET) release to the circulation represents a potentially important target for interventions aiming to reduce mortality in CKD patients. In this minireview, we propose that there are several potential sources of endotoxemia in CKD and that gut translocation, leading to the generation of ligands of the innate immune response, represents a potentially reversible cause. Prevention of endotoxemia, through treating foci of ET (periodontal disease, catheters, vascular access) or reducing translocation from the gut, will potentially reduce the inflammatory response.

NMR and luminescence experiments reveal the structure and symmetry adaptation of a europium ionic liquid to solvent polarity.

By combining NMR data (nuclear Overhauser effect and pseudocontact shifts) with luminescence measurements, we uncover how the structure of an anionic europium complex adapts to different solvent polarities as a result of the different relative proximities of the ion pairs. In nonpolar solvents, the detected contact ion pairs, CIPs, indicate that the ions remain in proximity, with the molecular cation, and then perturbing and distorting the coordination polyhedron of the anion complex to a low symmetry configuration, which promotes luminescence. Differently, solvent separated ion pairs occur in polar solvents, indicating that the molecular ions have been disconnected. Thus, in polar solvents, the europium complex anion becomes free from the close influence of the molecular cation, allowing the coordination polyhedron to increase its symmetry, which in turn reduces the luminescence of the anionic europium complex. This reduction of coordination polyhedron symmetry by the close proximity of the molecular cation in nonpolar solvents was confirmed by additional photophysical measurements combined with quantum chemical RM1 calculations, suggesting that, in nonpolar solvents, the symmetry point group of the coordination polyhedron is C1, whereas in polar solvents it is either D2d or S4. The nonpolar solvents used were benzene, chloroform and dichloromethane; and the polar ones were acetone and acetonitrile. The synthesized ionic liquids were tetrakis [C5mim][La(BTFA)4] and [C5mim][Eu(BTFA)4], where BTFA stands for 4,4,4-trifluoro-1-phenyl-1,3-butanedione, lanthanoids (La3+ and Eu3+) and C5mim stands for 1-methyl-3-isopentylimidazolium. They were synthesized by a microwave methodology that is both fast and green (the synthetic reaction takes about 15 min) and also leads to more easily purifiable crystals.

Association between biomarkers of carbonyl stress with increased systemic inflammatory response in different stages of chronic kidney disease and after renal transplantation.

BACKGROUND: Chronic kidney disease (CKD) is characterized by progressive kidney dysfunction accompanied by accumulation of uremic toxins and a potential disequilibrium between the redox status and the generation of prooxidants, resulting in oxidative stress and chronic inflammation which is associated with complications (particularly cardiovascular disease) in this population. We aimed to analyze the concentration of total plasma thiols (indicator of antioxidant capacity) and the protein carbonyl content (a marker of carbonyl stress) in relation to kidney function and inflammation in a group of patients with CKD. PATIENTS AND METHODS: A group of 68 patients with CKD (stages 2-5; mean age 57 ± 12 years, 46% male, 34% diabetics) and another group of 21 patients who underwent living donor kidney transplantation (mean age 36 ± 17 years, 50% male, 10% diabetics, and 9 ± 2 months after renal transplantation) were included in the study. Total plasma thiol and protein carbonyl levels were determined by the DTNB and DNPH methods, respectively, and were adjusted to the plasma albumin concentrations. Plasma levels of fibrinogen and C-reactive protein (CRP) were measured by routine methods and used as markers of inflammation. RESULTS: Mean glomerular filtration rate (GFR) was 48 ml/min, and there was a positive correlation between GFR and thiol (r = 0.25, p < 0.05) and a negative correlation between GFR and carbonyl (r = -0.26, p < 0.05), fibrinogen (r = -0.45, p < 0.0001) and CRP (r = -0.14, p = ns). Carbonyl strongly correlated with CRP (0.49, p < 0.0001) and fibrinogen (0.30, p < 0.01). There was a significant reduction in plasma carbonyl after renal transplantation (1.4 ± 0.4 nmol/mg albumin), compared with the levels before the procedure (2.0 ± 1.4 nmol/mg albumin, p < 0.05), which parallels an improvement in thiol levels (15 ± 4 vs. 21 ± 5 nmol/mg albumin, p < 0.001). In addition, there was a significant correlation between CRP and carbonyl after the transplantation (r = 0.65; p < 0.005). CONCLUSION: We observed that patients with CKD present an altered redox status and increased signs of carbonyl stress and inflammatory activity as kidney function deteriorates, which was partially but significantly improved after renal transplantation. These findings indicate the importance of renal function in the complications of CKD related to oxidative stress and inflammation.

Sevelamer carbonate reduces inflammation and endotoxemia in an animal model of uremia.

BACKGROUND: Renal failure is associated with activation of inflammatory response, but the mechanisms behind this observation and potential anti-inflammatory strategies are yet to be defined. Endotoxin (ET) translocation from the intestinal lumen can potentially trigger systemic inflammatory response, and ET binding represents a potential anti-inflammatory strategy in renal failure. The aim of this study was to evaluate the ET-binding capacity of sevelamer carbonate in an animal model of renal failure. MATERIAL AND METHODS: Rats were 5/6 nephrectomized to induce uremia (U) and sham-operated rats were allocated to receive normal chow (controls) or a diet with 3% sevelamer carbonate added (+SC) for 60 days. Tumor necrosis factor-α (TNF-α) and ET were measured in plasma on days 7, 30 and 60 in all animals. RESULTS: Renal failure induced an inflammatory response, since TNF-α levels were undetectable in all control animals in contrast to the uremic group (3.18 ± 0.62, 2.58 ± 0.54 and 1.86 ± 0.47 pg/ml, respectively, on days 7, 30 and 60; p < 0.05 at all time points). Similarly, uremic rats presented an increase in ET levels (0.038 ± 0.007 EU/ml) when compared to sham-operated animals (0.008 ± 0.006 EU/ml; p < 0.05). During the study, TNF-α levels in U + SC rats were significantly lower compared with U-control animals (p < 0.05). Similarly, ET levels in U + SC rats were lower when compared with U-control rats (p < 0.005). CONCLUSION: In conclusion, induction of renal failure triggered inflammation and induced endotoxemia in this experimental model of chronic kidney disease, which were reduced by sevelamer treatment. This data suggests that sevelamer carbonate induces an anti-inflammatory effect in parallel to a reduction in ET.

Apathy in frontotemporal dementia is related to medial prefrontal atrophy and is independent of executive dysfunction.

INTRODUCTION: Apathy is the most common neuropsychiatric syndrome in behavioral variant frontotemporal dementia (bvFTD), and encompasses cognitive, behavioral and affective symptoms. The neural basis of apathy in bvFTD is not completely understood. Previous neuroimaging studies have poorly considered executive impairment and dementia severity as possible confounding factors. Herein we investigated the neural basis of apathy in bvFTD through structural neuroimaging taking into account these factors. METHODS: We included patients with probable bvFTD (n = 21) and cognitively healthy controls (HC, n = 22). Participants were matched for age, sex and schooling. All subjects underwent a thorough neuropsychological examination, including tests for executive functions and social cognition. Apathy was assessed with the Starkstein Apathy Scale (SAS). All subjects underwent 3T brain MRI. We investigated correlations between SAS scores and gray matter atrophy within the bvFTD group. Executive function (Frontal Assessment Battery) and disease severity were considered as covariates in neuroimaging analyses. RESULTS: Compared to HC, bvFTD patients had lower scores on global cognitive efficiency, executive functions and social cognition. All bvFTD had clinically relevant apathy (scores greater than 14 in the SAS). Performance in executive function tests did not correlate with apathy scores. The severity of apathy was negatively correlated with gray matter volumes in midline prefrontal regions, namely orbitofrontal cortex and both anterior and dorsal regions of cingulate cortex. CONCLUSIONS: Apathy in bvFTD is related to a specific network of prefrontal cortical areas critically involved in effort-based behavior for rewards and appears to be independent of executive dysfunction.

Global DNA methylation of peripheral blood leukocytes from dogs bearing multicentric non-Hodgkin lymphomas and healthy dogs: A comparative study.

Non-Hodgkin lymphomas are among the most common types of tumors in dogs, and they are currently accepted as comparative models of the disease in humans. Aberrant patterns of DNA methylation seem to play a key role in the development of hematopoietic neoplasms in humans, constitute a special mechanism of transcriptional control, and may be influenced by genetic and environmental factors. Blood leukocyte DNA global methylation has been poorly investigated in dogs. The aim of this study is to examine whether peripheral blood global DNA methylation is associated with canine multicentric lymphomas. Peripheral venous blood samples from ten healthy dogs and nine dogs bearing multicentric lymphomas were collected, and the buffy coat was separated. Global DNA methylation was analyzed by High Performance Liquid Chromatography (HPLC) and immunocytochemistry (ICC). In both analyses, leukocytes from dogs with lymphoma presented lower global DNA methylation than in healthy dogs (HPLC: p = 0.027/ 5MeCyt immunoreactivity scores: p = 0.015). Moderate correlation was observed between the results obtained by HPLC and ICC (correlation coefficient = 0.50). For the identification of differently methylated genes between both groups, the Infinium Human Methylation (HM) EPIC BeadChip (850K) was used. Of the 853,307 CpGs investigated in the microarray, there were 34,574 probes hybridized in the canine samples. From this total, significant difference was observed in the methylation level of 8433 regions, and through the homologous and orthologous similarities 525 differently methylated genes were identified between the two groups. This study is pioneer in suggesting that dogs bearing non-Hodgkin lymphoma presented DNA global hypomethylation of circulating leukocytes compared with healthy dogs. Although canine samples were used in an assay developed specifically for human DNA, it was possible to identify differently methylated genes and our results reiterate the importance of the use of peripheral blood leukocytes in cancer research and possible new biomarkers targets.

Association between body mass index and body fat in chronic kidney disease stages 3 to 5, hemodialysis, and peritoneal dialysis patients.

OBJECTIVE: Chronic kidney disease (CKD) patients may present with altered body composition. Body mass index (BMI) is a simple method for evaluating body fat mass (FM) in the general population. In CKD patients, there are few reports demonstrating the association between BMI and body composition. Our objective was to investigate the reliability of BMI as an indicator of FM in patients with CKD stages 3 to 5. METHODS: Seventy-eight nondiabetic CKD patients (aged 48, SD +/- 12 years; 45% male) and 30 healthy control subjects (aged 46, SD +/- 12 years; 40% male), matched for age and sex, were evaluated. Chronic kidney disease patients were divided, according to K/DOQI guidelines, into 27 subjects at stages 3 to 4 (mean glomerular filtration rate of 43 +/- 12 mL/minute; age, 52 +/- 10 years), and 51 at stage 5: 25 in hemodialysis (HD) (aged 45, SD +/- 12 years; 44% male), and 26 in peritoneal dialysis (PD) (aged 49, SD +/- 13 years; 42% male). Body mass index was calculated as weight/height(2), and body composition was evaluated through dual-energy x-ray absorptiometry. RESULTS: There was no difference in median BMI (kg/m(2)) among healthy control subjects (24.8; range, 19.2-34.1), CKD stages 3 to 4 (26.4; range, 20.4-37.6), HD patients (24.5; range, 19.4-35.7), and PD patients (24.5; range, 20.2-37.7; P > .05). Likewise, no significant difference was verified in median body FM (kg) among control subjects (18.8; range, 9.2-36.5), CKD stages 3 to 4 (21.2; range, 11.6-37.9), HD patients (17.1; range, 4.8-38.9), and PD patients (20.1; range, 6.5-41.5; P > .05). Moreover, a positive and significant correlation was found between BMI and FM (kg) in CKD stages 3 to 4 (Rho = 0.67, P = .0002), in HD patients (Rho = 0.67, P = .0002), in PD patients (Rho = 0.79, P < .0001), and in control subjects (Rho = 0.79, P < .0001). Although BMI and lean body mass (in kg) was significantly correlated in CKD stages 3 to 4 (Rho = 0.58, P = .001) and healthy control subjects (Rho = 0.30, P = .007), no significant correlation was found in HD patients (Rho = 0.19, P = .34) and in PD patients (Rho = 0.17, P = .38). CONCLUSIONS: Body composition did not differ in patients with CKD stages 3 to 5, and between dialysis modalities. Although BMI was strongly and significantly correlated with body FM in CKD patients at stages 3 to 5, lean body mass was not. These findings suggest that BMI is a reliable indicator of body FM in this CKD population.

Europium Complexes: Luminescence Boost by a Single Efficient Antenna Ligand.

We advance the concept that a single efficient antenna ligand substituted in or added to an otherwise weakly luminescent europium complex is enough to significantly boost its luminescence. Our results, on the basis of photophysical measurements on 5 novel europium complexes and 15 known ones, point in the direction that ligand dissimilarity and ligand diversity are all concepts that clearly play a fundamental role in the luminescence of europium complexes. We show that it is important that a symmetry breaker ligand exists in the complex to enhance ligand dissimilarity and ligand diversity, all mainly affecting the nonradiative decay rate by reducing it. Because the presence of at least one antenna ligand is also obviously necessary, the optimal and the most cost-effective situation can be achieved by adding a single coordination symmetry breaker that is also an efficient antenna, such as 1-(2-thenoyl)-3,3,3-trifluoroacetone or 4,4,4-trifluoro-1-phenyl-1,3-butanedione. In such cases the quantum efficiency, η, is decidedly boosted, as can be verified by going from complex [EuCl2(TPPO)4]Cl·3H2O with η = 0% to the novel complex [EuCl2(BTFA)(TPPO)3], where TPPO stands for triphenylphosphine oxide, with η = 62%.

Chemical Partition of the Radiative Decay Rate of Luminescence of Europium Complexes.

The spontaneous emission coefficient, Arad, a global molecular property, is one of the most important quantities related to the luminescence of complexes of lanthanide ions. In this work, by suitable algebraic transformations of the matrices involved, we introduce a partition that allows us to compute, for the first time, the individual effects of each ligand on Arad, a property of the molecule as a whole. Such a chemical partition thus opens possibilities for the comprehension of the role of each of the ligands and their interactions on the luminescence of europium coordination compounds. As an example, we applied the chemical partition to the case of repeating non-ionic ligand ternary complexes of europium(III) with DBM, TTA, and BTFA, showing that it allowed us to correctly order, in an a priori manner, the non-obvious pair combinations of non-ionic ligands that led to mixed-ligand compounds with larger values of Arad.

Faster Synthesis of Beta-Diketonate Ternary Europium Complexes: Elapsed Times & Reaction Yields.

ß-diketonates are customary bidentate ligands in highly luminescent ternary europium complexes, such as Eu(ß-diketonate)3(L)2, where L stands for a nonionic ligand. Usually, the syntheses of these complexes start by adding, to an europium salt such as EuCl3(H2O)6, three equivalents of ß-diketonate ligands to form the complexes Eu(ß-diketonate)3(H2O)2. The nonionic ligands are subsequently added to form the target complexes Eu(ß-diketonate)3(L)2. However, the Eu(ß-diketonate)3(H2O)2 intermediates are frequently both difficult and slow to purify by recrystallization, a step which usually takes a long time, varying from days to several weeks, depending on the chosen ß-diketonate. In this article, we advance a novel synthetic technique which does not use Eu(ß-diketonate)3(H2O)2 as an intermediate. Instead, we start by adding 4 equivalents of a monodentate nonionic ligand L straight to EuCl3(H2O)6 to form a new intermediate: EuCl3(L)4(H2O)n, with n being either 3 or 4. The advantage is that these intermediates can now be easily, quickly, and efficiently purified. The ß-diketonates are then carefully added to this intermediate to form the target complexes Eu(ß-diketonate)3(L)2. For the cases studied, the 20-day average elapsed time reduced to 10 days for the faster synthesis, together with an improvement in the overall yield from 42% to 69%.

Job satisfaction of nursing staff in a university hospital.

OBJECTIVE: identify the determinants of job satisfaction of the nursing staff of a public university hospital. METHOD: secondary study with mixed data approach and simple and multiple linear regression. A total of 115 subjects participated in the study, 41 nurses and 74 nursing assistants and technicians. The data collection occurred in 2013 using the QST-Caism questionnaire. RESULTS: education, hierarchical level and workplace constitute job satisfaction determinants. However, age, gender, job and work period did not show this relationship. More educated workers held low job satisfaction if exercised not graduated nursing functions. CONCLUSION: graduated workers who perform high school functions are more unsatisfied than those who have high school function and qualification.

Effect of preload reduction by hemodialysis on left atrial volume and echocardiographic Doppler parameters in patients with end-stage renal disease.

Left atrial (LA) volume has been proposed as a less preload-dependent parameter of diastolic function than Doppler mitral inflow. We hypothesize that in the absence of mitral regurgitation and atrial fibrilation, LA enlargement could be a more practical (and relatively preload-independent) method for the evaluation of left ventricular diastolic function. The aim of the present study was to determine the effects of preload reduction by hemodialysis on LA volume.

Efficient chiral discrimination by 77Se NMR.

[reaction: see text] Several (77)Se NMR experiments were performed by titrating a sample of selenides with the chiral shift reagent methylbenzylamine (MBA), followed by acquisition of (77)Se NMR spectra. Eventually, we observed the appearance of two anisochronous resonances, with a relatively large separation, from 37 to 56 Hz, corresponding to the formation of the diastereomeric complexes. This methodology avoids derivatization processes, and the studied compound can be easily recovered from the NMR tube.