Synthesis and Fluorescence Properties of Imidazopyridine-Linked Coumarins via Tandem C(sp2)-H Functionalization/Decarboxylation Reaction.

A catalyst-, oxidant-free and green synthetic route for direct access to a series of novel imidazopyridine-linked coumarins has been devised through tandem C(sp2)-H functionalization/decarboxylation reaction in ethyl acetate as a sustainable medium. Moreover, the utilities of ensured products in further organic synthesis were conducted by Suzuki-Miyaura and Sonogashira cross-coupling reactions. The fluorescence characteristics of the produced molecules are appropriate, and the synthesized scaffolds could promisingly garner future attention in clinical diagnostics and bioimaging research.

Epidemiological features of COVID-19 in Iran.

Background: The first confirmed case of COVID-19 in Iran was reported in February 2019. The current study aimed to investigate the epidemiological aspects of COVID-19 disease in Isfahan province and evaluate the chances of infection and death in the population. Materials and Methods: In this cross-sectional study, 21,203 confirmed cases of COVID-19, based on the polymerase chain reaction test, referred to outpatient facilities from February 2019 to July 2020 in Isfahan province are studied. Disease incidence, mortality, and case fatality rate, as well as odds ratio (OR) of infection and death, were calculated and analyzed using SPSS version 20. Results: The highest incidence of the disease was within the age group of 30-39 years 4911 (23.9%) and males 11,561 (54.5%). Mortality in people over 80 years (207 [32.9%]), men (370 cases [58.7%]), diabetics (182 cases [28.9%]), and people with cardiovascular disease (165 people [26.2%]) was more. In multivariate analysis, patients with a cancer diagnosis had the highest OR of death (OR = 4.03 confidence interval [CI]: 2.56-6.35) (P < 0.001), followed by those with immune deficiency disease (OR = 2.46 CI: 1.07-5.63) (P = 0.03). As the number of comorbidities increased, the risk of death increased in the total population, so that in patients with more than 4 underlying diseases, compared to the group without disease, the chance of death increased 6.33 times. Conclusion: This study showed that people with cancer and chronic respiratory disease had a higher chance of COVID-19 infection. People over the age of 60, people with cancer, and immunodeficiency also had a higher chance of COVID-19 mortalityW.

Epidemiological Status and Health System Screening of COVID 19 Hospitalized Patients in Isfahan, Iran.

Background: The first case of Covid-19 disease was identified in Iran on February 19, 2020, and spread rapidly throughout the country. The aim of this study was to investigate the characteristics of COVID-19 hospitalized patients in Isfahan province of Iran from February 29, 2020, to July 21, 2020, and evaluate the effect of health system screening on the final outcome patients. Methods: In this cross-sectional study, all patients with positive COVID-19 PCR test and patients with negative PCR test but suspected clinical symptoms of COVID 19, admitted to Isfahan hospitals from February 29 to July 21were included in the study and the epidemiological characteristics of patients such as demographic characteristics, underlying disease, early signs and symptoms and the final outcomes of patients were analyzed using SPSS software version 20. Results: Of 11817 inpatients with COVID-19, 6590 (55.9%) were male, 1222 (10.4%) died, 9759 (82.8%) were discharged, and 4324 (36.7%) of hospitalized patients were asymptomatic. Among the hospitalized patients, 4642 (35.8%) had received primary screening services, and the mean age of the screened patients was statistically significantly higher than the group without primary screening (58.9±20.61, 55.08±21.57, P=0.068). 6914 (64.6%) of hospitalized patients had a positive initial PCR test, which was statistically significantly higher in patients with diabetes and an early symptom of sore throat. The Odds Ratio (OR) of readmission was most significantly associated with underlying cancer (OR=3.05, CI 95% 1.31-7.1) (P=0.011). The rate of readmission was statistically significantly higher in elderly, rural residents, and patients with underlying disease, diabetic, and hypertensive patients (P<0.05). Conclusion: This study showed that about half of the people who tested positive for COVID- 19 needed to be hospitalized, and about 9 percent mostly diabetic and hypertensive patients, needed readmission. More than half of the hospitalized people were not screened by the health system. However, screening by the health system had no effect on the length of hospital stay and disease outcome.

Isfahan and Covid-19: Deep spatiotemporal representation.

The coronavirus COVID-19 is affecting 213 countries and territories around the world. Iran was one of the first affected countries by this virus. Isfahan, as the third most populated province of Iran, experienced a noticeable epidemic. The prediction of epidemic size, peak value, and peak time can help policymakers in correct decisions. In this study, deep learning is selected as a powerful tool for forecasting this epidemic in Isfahan. A combination of effective Social Determinant of Health (SDH) and the occurrences of COVID-19 data are used as spatiotemporal input by using time-series information from different locations. Different models are utilized, and the best performance is found to be for a tailored type of long short-term memory (LSTM). This new method incorporates the mutual effect of all classes (confirmed/ death / recovered) in the prediction process. The future trajectory of the outbreak in Isfahan is forecasted with the proposed model. The paper demonstrates the positive effect of adding SDHs in pandemic prediction. Furthermore, the effectiveness of different SDHs is discussed, and the most effective terms are introduced. The method expresses high ability in both short- and long- term forecasting of the outbreak. The model proves that in predicting one class (like the number of confirmed cases), the effect of other accompanying numbers (like death and recovered cases) cannot be ignored. In conclusion, the superiorities of this model (particularity the long term predication ability) turn it into a reliable tool for helping the health decision-makers.

Association of IL-10, IL-18, and IL-33 genetic polymorphisms with recurrent pregnancy loss risk in Iranian women.

Recurrent pregnancy loss (RPL) is a heterogeneous disease with three or more consecutive abortions before 20 weeks of pregnancy. Recently, inflammatory factors such as interleukins (IL) have been found to be a significant factor in the RPL. The objective of this study was to investigate the association between RPL and IL-10 (rs1800896), IL-18 (rs1946518) and IL-33 (rs1929992) genes polymorphisms in Iranian women. The study participants consisted of 300 women with RPL and the control group comprised of 300 healthy women with successful delivery. Genomic DNA was extracted from peripheral blood, and genotyping was performed by polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP). There were no significant differences in the frequencies of genotype and allele in IL-10 gene polymorphism (rs1800896) between patients and control group (p > .005). In contrast, there were significant differences in the frequencies of CC genotype in IL-18 gene polymorphism (rs1946518) between patients and the control groups (p = .004; OR =0.990; 95% CI: 0.320-8.855). Also, there were significant differences in the frequencies of GA genotype in IL-33 gene polymorphism (rs1929992) between patients and the control groups (p = .001; OR =0.955; 95% CI: 0.239-9.807). Present study showed that the rs1800896 polymorphism (IL-10) might not play role in RPL in the Iranian population; whereas rs1946518 (IL-18) and rs1929992 (IL-33) polymorphisms may be associated with the risk of RPL in the Iranian women.

Synthesis of N-doped TiO2/SiO2/Fe3O4 magnetic nanocomposites as a novel purple LED illumination-driven photocatalyst for photocatalytic and photoelectrocatalytic degradation of naproxen: optimization and different scavenger agents study.

N-doped TiO2/SiO2/Fe3O4 as a new magnetic photocatalyst that is active in visible light has been prepared by simple sol-gel method. The prepared samples were characterized by XRD, FESEM, EDX, TEM, BET, BJH, VSM, XPS, FT-IR, and DRS-UV/Vis analysis. The photocatalytic effect of synthesized samples on naproxen degradation was studied. The operational parameters were optimized through central composite design to achieve maximum efficiency. The optimum values for maximum efficiency were obtained at pH of 4.29, catalyst mass of 0.06 g, naproxen concentration of 9.33 mg L-1, and irradiation time of 217.06 min. At these optimum conditions, the maximum photocatalytic degradation percentages of naproxen were found to be 96.32% at desirability function value of 1.0. Coupling the electrical current with the photocatalytic process proved that the electrical current was considerably efficient in decreasing the degradation time of removing the naproxen from aqueous solutions. The photocatalytic activity of the nanoparticles was also studied under sunlight. Considering the results provided by UV-Vis spectrophotometry and total organic carbon, it was found that the prepared samples are extraordinarily efficient to degrade naproxen under both purple LED and solar lights. Furthermore, the effect of different scavenger agents on naproxen degradation has been studied.

In vivo and in vitro impact of miR-31 and miR-143 on the suppression of metastasis and invasion in breast cancer.

PURPOSE: The microRNA (miR)-31 and miR-143 are pleiotropic anti-metastatic miRs, with an expression that decreases significantly in metastatic breast cancer cells. The aim of this study was to investigate the effect of miR-31 and miR-143 inhibition on metastasis and invasion in both MDA-MB231, MDA-MB468 as well as the MCF-7 breast cancer cell lines and 5-week old female mice. METHODS: Following the cloning of miR-31 and miR-143 into vectors, their expressions were determined before treatment with constructs of miR-31 and miR-143 in cancer cell lines and normal breast cells. Then miR-31 and miR-143 were transfected to the cell lines and the expression was assessed after 48 hrs. Moreover, the levels of migration and invasion were determined in cell lines. These experiments were performed in 5-week old female mice. RESULTS: The results showed that miR-31 expression before the transfection of miR-31 construct was decreased 4, 70 and 100 times in MCF-7, MDA-MB468 and MDA-MB231 cell lines, respectively, in comparison to normal breast cells; but after the transfection of miR-31 construct, the expression of miR-31 increased 80 times. Additionally, invasion and migration decreased by 15 and 10 times in MDAMB-468. All of the modifications in miR-143 were low in comparison to miR-31. The results of the in vivo experiments were approximately the same as in the in vitro experiments. CONCLUSIONS: It appears that the use of miR-31 is highly efficient than miR-143 in the inhibition of invasion and metastasis in breast cancer. Our study improved our conception about miR-31 and miR-143 and their roles in the identification and therapy of breast cancer.

Super-resolution of Retinal Optical Coherence Tomography Images Using Statistical Modeling.

Background: Optical coherence tomography (OCT) imaging has emerged as a promising diagnostic tool, especially in ophthalmology. However, speckle noise and downsampling significantly degrade the quality of OCT images and hinder the development of OCT-assisted diagnostics. In this article, we address the super-resolution (SR) problem of retinal OCT images using a statistical modeling point of view. Methods: In the first step, we utilized Weibull mixture model (WMM) as a comprehensive model to establish the specific features of the intensity distribution of retinal OCT data, such as asymmetry and heavy tailed. To fit the WMM to the low-resolution OCT images, expectation-maximization algorithm is used to estimate the parameters of the model. Then, to reduce the existing noise in the data, a combination of Gaussian transform and spatially constraint Gaussian mixture model is applied. Now, to super-resolve OCT images, the expected patch log-likelihood is used which is a patch-based algorithm with multivariate GMM prior assumption. It restores the high-resolution (HR) images with maximum a posteriori (MAP) estimator. Results: The proposed method is compared with some well-known super-resolution algorithms visually and numerically. In terms of the mean-to-standard deviation ratio (MSR) and the equivalent number of looks, our method makes a great superiority compared to the other competitors. Conclusion: The proposed method is simple and does not require any special preprocessing or measurements. The results illustrate that our method not only significantly suppresses the noise but also successfully reconstructs the image, leading to improved visual quality.

Deep learning for discrimination of active and inactive lesions in multiple sclerosis using non-contrast FLAIR MRI: A multicenter study.

BACKGROUND: Within the domain of multiple sclerosis (MS), the precise discrimination between active and inactive lesions bears immense significance. Active lesions are enhanced on T1-weighted MRI images after administration of gadolinium-based contrast agents, which brings about associated complexities. This study investigates the potential of deep learning to differentiate between active and inactive lesions in MS using non-contrast FLAIR-type MRI data, presenting a non-invasive alternative to conventional gadolinium-based MRI methods. METHODS: The dataset encompasses 9097 lesion images collected from 130 MS patients across four distinct imaging centers, with post-contrast T1-weighted images as the benchmark reference. We initially identified and labeled the lesions and carefully selected corresponding regions of interest (ROIs). These ROIs were employed as inputs for a convolutional neural network (CNN) to predict lesion status. Also, transfer learning was utilized, incorporating 12 pre-trained CNN models. Subsequently, an ensemble technique was applied to 3 of best models, followed by a systematic comparison of the results. RESULTS: Through a 5-fold cross-validation, our custom designed network exhibited an average accuracy of 85 %, a sensitivity of 95 %, a specificity of 75 %, and an AUC value of 0.90. Among the pre-trained models, ResNet50 emerged as the most effective, achieving a specificity of 58 %, an accuracy of 75 %, a sensitivity of 91 %, and an AUC value of 0.81. Our comprehensive evaluations encompassed the receiver operating characteristic curve, precision-recall curve, and confusion matrix analyses. CONCLUSION: The findings underscore the efficacy of the proposed CNN, trained on FLAIR MRI data ROIs, in accurately discerning active and inactive lesions without reliance on contrast agents. Our multicenter study of 130 patients with diverse imaging devices outperforms the other single-center studies, achieving superior sensitivity and specificity. Unlike studies using multiple modalities, our exclusive use of FLAIR images streamlines the process, and our streamlined approach, excluding conventional pre-processing, demonstrates efficiency. The external validation conducted on diverse datasets, coupled with the analysis of dilated masks, underscores the adaptability and efficacy of our custom CNN model in discerning between active and inactive lesions.

An efficient and practical approach for the synthesis of indoloquinolines and indolo/pyrroloquinoxalines via a Cu-catalyzed Ugi-C/Ugi-N-arylation sequence.

A Cu-catalyzed tandem transformation of Ugi adducts through CH/NH bond functionalization reactions was reported for synthesizing a broad spectrum of indolo/pyrrolo-[1,2-a]quinoxaline-6/4-carboxamide, 7H-indolo[2,3-c]quinoline-6-carboxamide, and 1-(cyclohexylamino)-14H-indolo[2,3-c][1,4]oxazino[4,3-a]quinolin-4(3H)-one derivatives in moderate to excellent yields. In this protocol the Ugi condensation of aromatic aldehydes, anilines, acids, and isocyanides leads to the formation of bis-amides in methanol at room temperature. This approach employed simple reaction conditions, including Ugi product as starting material, CuI, l-proline as a ligand, and cesium carbonate, in DMSO for 8 h. This method demonstrated efficiency in synthesizing fused-nitrogen-containing heterocycles through a convenient pathway.

Investigating the risk factors for isthmocele development after cesarean delivery.

BACKGROUND: Cesarean delivery rates are increasing globally, raising concerns about associated complications such as isthmocele. Isthmoceles are pouch-like defects in the anterior uterine wall at the site of a prior cesarean delivery scar. OBJECTIVE: This study aimed to determine isthmocele prevalence, associated symptoms, and risk factors among women with a history of cesarean delivery. STUDY DESIGN: This cross-sectional study evaluated 297 women with prior cesarean delivery using transvaginal ultrasound to screen for isthmocele. Data on demographics, pregnancy details, comorbidities, and indications for cesarean delivery were collected. Isthmocele was defined sonographically as any niche or defect at the hysterotomy site. Descriptive and comparative analyses identified factors associated with isthmocele. RESULTS: Isthmocele prevalence was 65.3% (n=194). Abnormal vaginal bleeding was reported in 21.1% of participants, pelvic pain by 4.1% of participants, and both by 4.1% of participants. Compared to women without isthmocele, those with isthmocele were older (35.9 vs 31.6 years), had higher body mass index (26.8 vs 25.5 kg/m2), gravidity (1.8 vs 1.3), and parity (1.7 vs 1.2). Repeat cesarean delivery was more common (30.4% vs 12.6%) and elective cesarean delivery less common (33.5% vs 67.9%) among those with isthmocele. CONCLUSION: Over half of the women with history of cesarean delivery had an isthmocele. Abnormal bleeding was common. Advanced maternal age, obesity, repeat procedures, and certain comorbidities appear to increase risk. Further research on prevention and treatment is warranted given the high prevalence.

The effect of sustainable low-dose sildenafil and cognitive-behavioral training on sexual function in methadone-treated men-a randomized controlled trial.

BACKGROUND: Sexual dysfunction caused by opioids is one of the serious problems of drug misusers. OBJECTIVE: This study aimed to evaluate and compare the effect of continuous low-dose sildenafil treatment alongside psychological training on the sexual function of methadone-treated patients. METHOD: This randomized clinical trial was conducted on methadone-treated men with sexual dysfunction. Patients were randomly divided into two treatment groups: sildenafil 25 mg and psychological training. Sexual Quality of Life-Men, Sexual Self-Efficacy Scale-Erectile, and the International Index of Erectile Function were used before and 4 weeks after the end of the intervention. RESULTS: A total of 67 couples were included in the study (34 psychological interventions vs. 33 sildenafil group). After 4 weeks of treatment, the mean of male erectile function (33.73 ± 8.114 and 27.62 ± 6.238, p = 0.003) and sexual self-efficacy score (78.36 ± 12.713 and 69.62 ± 14.940, p < 0.0001) in the sildenafil group were statistically significant compared to the psychological group, however, the sexual quality score of the two groups was not statistically significant (31.48 ± 9.216 and 31.71 ± 11.333, p = 0.342). CONCLUSIONS: The sexual function of methadone-treated men in both groups was significantly improved, yet this difference was significantly greater in the pharmaceutical treatment group than the trainings. As a result, due to the high need for treatment, any type of intervention (medication or psychotherapy) will be effective in these patients.

Investigating the effect of zinc supplementation on probability of relapse and mental health in patients with opioid use disorder undergoing methadone maintenance treatment.

BACKGROUND: Considering different factors, such as high withdrawal rates in methadone maintenance treatment (MMT) programs alongside mental health (MH) problems appearing in patients with opioid use disorder and the lack of prior research on the effect of zinc supplementation in this respect, the present study aimed to investigate the effect of zinc supplementation on the probability of relapse (PoR) and MH problems in patients with opioid use disorder undergoing MMT. METHODS: For this purpose, a randomized controlled trial with a clinical basis was fulfilled on a total of 68 patients with opioid use disorder receiving MMT, allocated to two groups, viz. intervention, and control (each one consisting of 34 individuals). Then, the participants in the intervention group were given zinc supplements combined with methadone for three months, and the controls only took methadone, according to the treatment plan. The data were collected using the Relapse Prediction Scale (RPS) and the Depression, Anxiety, and Stress Scale 21 (DASS-21) before, one month after, and at the end of the intervention program. FINDINGS: Compared to the control group, the likelihood of drug use (p = 0.01), drug craving (p = 0.002), and the RPS total score (p = 0.002) in the intervention group was significantly lower. Moreover, the results revealed a significant decreasing trend in depression (p = 0.01), anxiety (p < 0.001), stress (p = 0.001), and the DASS-21 total score (p = 0.001) in the intervention. Compared to the control group, the DASS-21 total score (p < 0.001) in the intervention group was significantly lower. CONCLUSION: Accordingly, it was concluded that zinc supplementation could reduce the PoR and improve MH problems in patients with opioid use disorder experiencing MMT. However, further research is recommended to fill the gaps. TRIAL REGISTRATION: The research protocol has also been listed on the Iranian Registry of Clinical Trials (IRCT) with code no. IRCT2020050904736N1.

Relation of Social Support Status and Social Health in People with Drug Abuse.

Background: The aim of this study was to investigate the status of social support in people with drug abuse and its relationship with social health in patients referring to addiction treatment centers in Isfahan. Materials and Methods: This cross-sectional study was performed in Isfahan addiction treatment centers in 2019-2020. The study population was the total number of people with drug abuse in Isfahan addiction treatment centers that 300 people with substance abuse and 300 people as control group were included. Social support and social health questionnaires were distributed among the participants. The Keez Social Health Questionnaire, designed in the United States in 2004, is about daily life and the social environment and measures social health. Another questionnaire was the social support of Sherbon and Stewart (MOS). This scale was a self-report tool that measured the amount of social support received by the subject. Results: The results showed a positive, direct, and significant relationship between the dimensions of social support and social health in the group of patients with drug abuse (P < 0.05). Comparison of social support and its dimensions in the two control and affected groups showed that the scores in the healthy group were significantly higher than the affected group (P < 0.05). Conclusion: According to the results of this study, the level of social support and social health in people with substance abuse is less than other people in society, and to improve the social health of people with substance abuse, more social support should be provided.

The Effect of Healthy Mental Lifestyle Package On Sleep Quality, Mental Health, and Lifestyle of Substance Users.

Background: The aim of this study was to assess the effect of a training package based on the lived experience of substance abusers on sleep problems and mental health. Materials and Methods: The current study was performed on 70 subjects equally distributed into two groups of control and intervention, Data collection tools included the Pittsburgh Sleep Quality Index (PSQI), the General Health Questionnaire (GHQ), and the Basic Adlerian Scales for Interpersonal Success-Adult Form (BASIS-A) Inventory. Data analysis was administered using the independent t-test, paired t-test, and MANCOVA. Statistical significance was considered when the P value < 0.05. Results: A total of 70 subjects participated in this study; 7 (10.6%) were females and 59 (89.4%) were males, with a mean age of 36.29 ± 8.588 years. The total score of PSQI was 12.48 (±4.206) and 13.16 (±3.397) for control and intervention groups, respectively, and declined to 12.33 (±4.442) and 9.56 (±4.45) after the intervention. The intervention resulted in an improved score for scales of belonging, going along, taking charge, harshness, being liked by all, and striving for perfection. Whereas the total score of the GHQ is reduced for both groups, that in the intervention group showed a higher decrease, which was also statistically significant. Conclusion: The developed training package successfully improved participants' sleep quality, mental health, and lifestyle.

The effect of Coronavirus disease pandemic on maternal and neonatal health: A cohort study from Isfahan, Iran.

Background: The Coronavirus disease-2019 (COVID-19) pandemic may profoundly impact on maternal and neonatal health worldwide. However, a few studies have investigated this topic. Objective: This study aimed to investigate the impact of the COVID-19 pandemic on maternal and neonatal health. Materials and Methods: This retrospective cohort study analyzed collected data from March to May 2020, and the same period in 2019, involving 5711 pregnant women referring to comprehensive healthcare centers in Isfahan province health facilities, Iran. Pregnant women and neonates were followed-up until 40 days after the delivery. Demographic characteristics, pre-pregnancy, antenatal care, and post-pregnancy variables were collected. Results: A total of 5711 pregnant women were studied, of whom 3477 (61%) were referred in 2019 (before the COVID-19 pandemic as nonexposed) and 2234 (39%) during the COVID-19 pandemic (as exposed group) in 2020. For those living in cities with a population of > 20,000, the number of antenatal care were lower about 2% compared to nonexposed group (p = 0.01). The number of mothers with a history of the underlying disease who referred to a comprehensive healthcare center during the COVID-19 pandemic (47%) was lower about 6% compared to nonexposed group (41%) (p < 0.001). During the COVID-19 pandemic, the prevalence of hypertension and gestational diabetes mellitus was 5% (n = 109) and 20% (n = 445), which were higher about 2% and 4%, respectively, compared to nonexposed group. The COVID-19 pandemic had no other significant effect on mothers' and neonates' other characteristics than nonexposed group. Conclusion: The COVID-19 pandemic imposes no significant effect on mothers' and neonates' health compared to nonexposed group.

Highly regioselective and diastereoselective synthesis of novel pyrazinoindolones via a base-mediated Ugi-N-alkylation sequence.

An efficient base-mediated/metal-free approach has been developed for the synthesis of 1-oxo-1,2,3,4-tetrahydropyrazino[1,2-a]indole-3-carboxamide derivatives via intramolecular indole N-H alkylation of novel bis-amide Ugi-adducts. In this protocol the Ugi reaction of (E)-cinnamaldehyde derivatives, 2-chloroaniline, indole-2-carboxylic acid and different isocyanides was designed for the preparation of bis-amides. The main highlight of this study is the practical and highly regioselective preparation of new polycyclic functionalized pyrazino derivatives. This system is facilitated by Na2CO3 mediation in DMSO and 100 °C conditions.

Cadmium(II) complex formation with selenourea and thiourea in solution: an XAS and 113Cd NMR study.

The complexes formed in methanol solutions of Cd(CF(3)SO(3))(2) with selenourea (SeU) or thiourea (TU), for thiourea also in aqueous solution, were studied by combining (113)Cd NMR and X-ray absorption spectroscopy. At low temperature (~200 K), distinct (113)Cd NMR signals were observed, corresponding to CdL(n)(2+) species (n = 0-4, L = TU or SeU) in slow ligand exchange. Peak integrals were used to obtain the speciation in the methanol solutions, allowing stability constants to be estimated. For cadmium(II) complexes with thione (C═S) or selone (C═Se) groups coordinated in Cd(S/Se)O(5) or Cd(S/Se)(2)O(4) (O from MeOH or CF(3)SO(3)(-)) environments, the (113)Cd chemical shifts were quite similar, within 93-97 ppm and 189-193 ppm, respectively. However, the difference in the chemical shift for the Cd(SeU)(4)(2+) (578 pm) and Cd(TU)(4)(2+) (526 ppm) species, with CdSe(4) and CdS(4) coordination, respectively, shows less chemical shielding for the coordinated Se atoms than for S, in contrast to the common trend with increasing shielding in the following order: O > N > Se > S. In solutions dominated by mono- and tetra-thiourea/selenourea complexes, their coordination and bond distances could be evaluated by Cd K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy. At ~200 K and high excess of thiourea, a minor amount (up to ~30%) of [Cd(TU)(5-6)](2+) species was detected by an upfield shift of the (113)Cd NMR signal (up to 423 ppm) and an amplitude reduction of the EXAFS oscillation. The amount was estimated by fitting linear combinations of simulated EXAFS spectra for [Cd(TU)(4)](2+) and [Cd(TU)(6)](2+) complexes. At room temperature, [Cd(TU)(4)](2+) was the highest complex formed, also in aqueous solution. Cd L(3)-edge X-ray absorption near edge structure (XANES) spectra of cadmium(II) thiourea solutions in methanol were used to follow changes in the CdS(x)O(y) coordination. The correlations found from the current and previous studies between (113)Cd NMR chemical shifts and different Cd(II) coordination environments are generally useful for evaluating cadmium coordination to thione-containing or Se-donor ligands in biochemical systems or for monitoring speciation in solution.

Tetra-aqua-bis-(thio-urea-κS)cadmium(II) triaqua-tris(thio-urea-κS)cadmium(II) disulfate.

The title compound, [Cd(CH(4)N(2)S)(2)(H(2)O)(4)][Cd(CH(4)N(2)S)(3)(H(2)O)(3)](SO(4))(2), contains two mol-ecules of each of the Cd complexes and four sulfate ions in the asymmetric unit: all the Cd atoms exhibit distorted octa-hedral geometries. The Cd-S and Cd-O bond lengths around the Cd atoms in the bis-(thio-urea) cations are in the ranges 2.580 (4)-2.599 (4) and 2.323 (8)-2.421 (9) Å, respectively, and the S atoms are in a cis orientation. In the tris-(thio-urea) cations, the corresponding bond lengths around the Cd atoms are slightly longer and are in the ranges 2.559 (4)-2.706 (3) and 2.303 (7)-2.480 (10) Å, respectively, and the S atoms are in a fac disposition. The crystal structure features numerous N-H⋯O, N-H⋯N, O-H⋯O and O-H⋯N hydrogen bonds. Two O atoms of a sulfate anion were found to be disordered over two orientations in a 0.620 (9):0.380 (9) ratio. The crystal studied was a racemic twin with BASF = 0.17 (5).