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1.
Rev Assoc Med Bras (1992) ; 70(1): e20230720, 2024.
Article in English | MEDLINE | ID: mdl-38198394

ABSTRACT

BACKGROUND: Antioxidants have been considered a rational curative strategy to prevent and cure liver diseases involving oxidative stress. An acute obstructive jaundice rat model was established to investigate the in vivo hepatoprotective efficacy of Rosa pimpinellifolia L. METHODS: The experimental jaundice model was performed by binding the main bile duct in 25 male Sprague-Dawley rats. All rats were randomly divided into five groups: first group: laparotomy-sham-only, second group: biliary tract binding (control), and third, fourth, and fifth groups: treatment groups with 250, 500, and 750 mg/kg fruit extracts daily, respectively. RESULTS: Considering dosage, although there was no significant therapeutic effect in the 250 mg/kg of Rosa pimpinellifolia L. group, the best results were found in the 500 mg/kg dose group, while results in the 750 mg/kg dose group showed consistent correlation with proinflammatory response. With regard to biochemical parameters, lipid hydroperoxide level in the rat serum and liver tissue was significantly decreased in all treatment groups. Amadori products, which are one of the early markers of glycol-oxidative stress, showed statistical significance in the treatment. CONCLUSION: It was revealed that the antioxidant effect of Rosa pimpinellifolia L. was more prominent in the early stages of hepatic injury secondary to oxidative stress.


Subject(s)
Antioxidants , Rosa , Male , Animals , Rats , Rats, Sprague-Dawley , Antioxidants/pharmacology , Antioxidants/therapeutic use , Fruit , Liver , Plant Extracts/pharmacology , Plant Extracts/therapeutic use
2.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 70(1): e20230720, 2024. tab
Article in English | LILACS-Express | LILACS | ID: biblio-1529352

ABSTRACT

SUMMARY BACKGROUND: Antioxidants have been considered a rational curative strategy to prevent and cure liver diseases involving oxidative stress. An acute obstructive jaundice rat model was established to investigate the in vivo hepatoprotective efficacy of Rosa pimpinellifolia L. METHODS: The experimental jaundice model was performed by binding the main bile duct in 25 male Sprague-Dawley rats. All rats were randomly divided into five groups: first group: laparotomy-sham-only, second group: biliary tract binding (control), and third, fourth, and fifth groups: treatment groups with 250, 500, and 750 mg/kg fruit extracts daily, respectively. RESULTS: Considering dosage, although there was no significant therapeutic effect in the 250 mg/kg of Rosa pimpinellifolia L. group, the best results were found in the 500 mg/kg dose group, while results in the 750 mg/kg dose group showed consistent correlation with proinflammatory response. With regard to biochemical parameters, lipid hydroperoxide level in the rat serum and liver tissue was significantly decreased in all treatment groups. Amadori products, which are one of the early markers of glycol-oxidative stress, showed statistical significance in the treatment. CONCLUSION: It was revealed that the antioxidant effect of Rosa pimpinellifolia L. was more prominent in the early stages of hepatic injury secondary to oxidative stress.

3.
Sisli Etfal Hastan Tip Bul ; 57(4): 479-484, 2023.
Article in English | MEDLINE | ID: mdl-38268651

ABSTRACT

Objectives: While metastatic breast cancer (MBC), which is the most common cause of death in women, has been seen as an incurable surgical problem in the past decade, as the heterogeneous nature of breast cancer becomes clear with increasing molecular studies and advances in oncological protocols, life expectancy is increasing. In this study, we aimed to examine the clinicopathological features of the patients we followed up with MBC. Methods: Patients who were operated on with the diagnosis of breast cancer in our hospital between 2018 and 2023 and who were later found to have metastases were retrospectively analyzed from the database. The age of the patients, the histological and molecular type, stage and grade of the tumor, the time from diagnosis to metastasis, the location of metastasis, the duration of treatment and follow-up were investigated. Patients who were operated on in other centers and/or were out of follow-up were excluded from the study. For the statistical analysis of the findings, number cruncher statistical system (NCSS) 2020 statistical software (NCSS LLC, Kaysville, Utah, USA) was used at a significance level of 0.05. Results: Metastasis was detected in 77.1% (n=37) of a total of 48 female patients, and recurrence was found in 22.9% (n=11). The mean age of the patients was 57 years. There was no statistically significant difference between the patients in terms of demographics. When evaluated according to the TNM stage, 24.3% (n=9) of the patients were in the early stage and 75.7% (n=28) were in the locally advanced stage; the number of locally advanced patients was found to be higher than the early stage. In histology examination, 27.1% (n=13) of the patients were luminal A, 31.3% (n=15) luminal B, 16.7% (n=8) HER2 positive, and 25% (n=12) triple negative. Ki67 was higher than 14% in 64.6% (n=31) patients. Breast conserving surgery was performed in 41.6% (n=20) of the patients, and mastectomy was performed in 58.3% (n=28) patients. Metastasis in 34.2% (n=13) of the cases within 1-2 years, in 42.1% (n=16) within 2-5 years, and in 23.7% (n=9) after 5 years took place. Sites of metastasis were bone (37.7%, n=28), liver (28.9%, n=11), brain (10.5%, n=4), and lung (7.9%, n=3). More than one metastasis site was observed in 21.05% (n=8) of patients with metastases. There was no statistically significant difference between luminal A, luminal B, HER 2 groups and triple-negative breast cancer in terms of metastasis time and location (p>0.05). Adjuvant hormone therapy was more common in the luminal A group, whereas neoadjuvant therapy was more common in the HER2+ group. A total of 20 deaths were observed in 48 patients (41.7%). The median disease-free survival was 64 months. Conclusion: Despite all the developments in metastatic breast cancer, the 5-year survival rate is 27%. Targeted personalized therapies may be promising when the mechanism of metastasis and specific pathways in breast cancer emerge.

4.
Front Surg ; 10: 1332142, 2023.
Article in English | MEDLINE | ID: mdl-38269392

ABSTRACT

Introduction: Axillary complete response (pCR) was observed in approximately half of breast cancer patients who received neoadjuvant chemotherapy (NAC) due to axillary positivity. Preventing axillary morbidity due to unnecessary axillary lymph node dissection (ALND) is extremely important for patients' quality of life. Targeted axillary dissection (TAD) is a technique developed to improve axillary staging and reduce the false negative rate in sentinel lymph node biopsy. Methods: Patients with cN1-N2 (clinically node) breast cancer whose axillary lymph node metastasis was confirmed by biopsy and who received NAC marked with a clip were included in the study. Patients who achieved clinical response after systemic treatment underwent sentinel lymph node biopsy (SLNB) with additional methods such as methylene blue guided dissection, skin marking for clip on lymph node (CLN) localization, and wire guided with imaging excision of the CLN. TAD and ALND pathology results were evaluated and analyzed with patient and tumor characteristics. Results: 83 patients who met the eligibility criterias for the study were examined retrospectively. 21 of the patients underwent TAD alone, and 62 patients underwent ALND after TAD. CLN rate was 98.8% in patients underwent only TAD and this rate was increased to 100% in patients underwent ALND after TAD. FNR in SLN, CLN, and TAD were 28.6%, 10.7%, and 3.6%, respectively. Conclusion: TAD is a feasible and reliable surgical approach to detect axillary residual disease with a high success rate.

5.
Curr Psychol ; : 1-19, 2022 Dec 16.
Article in English | MEDLINE | ID: mdl-36540693

ABSTRACT

With the acceleration of internet use, problematic social media use (PSMU) is included in our lives. When looking at the antecedents of PSMU, being young has been found to be a risk factor for PSMU. In addition to the benefits of technological advances in education and training, rapid technological developments may also result in problematic behaviors, especially among children and young. Recently, possibilities brought by technology and more widespread use of technology by young people have created a new concept, namely, cyberbullying. The present study aims to examine the effects of attachment anxiety and avoidance on PSMU and cyberbullying as with the partial mediating effects of the Dark Triad personality traits, angry rejection sensitivity, and anxious rejection sensitivity among adolescents. In general, the findings supported the proposed theoretical model. The results are discussed in terms of theoretical and practical implications along with suggestions for future research.

6.
Acta Crystallogr C Struct Chem ; 78(Pt 7): 390-397, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35788503

ABSTRACT

In the present study, N-(thiophen-2-ylmethyl)thiophene-2-carboxamide, C10H9NOS2, (I), was obtained by the reaction of thiophene-2-carbonyl chloride and thiophen-2-ylmethanamine. Characterization of (I) was carried out using X-ray diffraction, spectroscopic techniques and elemental analyses. The DFT/B3LYP/6-311++G(d,p) theoretical level was successfully applied to calculate the optimized geometry and the local and global chemical activity parameters. The results obtained show good agreement between the experimental and theoretical geometrical parameters. The local and global chemical activity parameters were examined to determine the electrophilic and nucleophilic sites in (I). The natural bond orbital (NBO) analysis of (I) gives an efficient methodology for investigating the inter- and intramolecular bonding, as well as giving a convenient basis for investigating charge transfer or conjugative interactions in molecular systems. Also, the antimicrobial activity of (I) was investigated against eight microorganisms using the microdilution method and it is found to have an effective antibacterial activity. In addition, molecular docking studies were calculated in order to understand the nature of the binding of (I) with a lung cancer protein (PDB entry 1x2j).


Subject(s)
Anti-Infective Agents , Thiophenes , Crystallography, X-Ray , Hydrogen Bonding , Models, Molecular , Molecular Conformation , Molecular Docking Simulation , Spectroscopy, Fourier Transform Infrared , Thiophenes/pharmacology , X-Rays
7.
Cureus ; 14(4): e23911, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35530825

ABSTRACT

Gallstone ileus is a rare form of mechanical intestinal obstruction. It is associated with high mortality and morbidity in the elderly population. The treatment of gallstone ileus includes more than one surgical option and it is appropriate to determine the surgical technique according to the general condition of the patient. In our case report, we present an 83-year-old patient who was admitted to the emergency room due to nausea and vomiting, was diagnosed with gallstone ileus, and had a cardiac arrest just before surgery. The patient management and the following surgical approach are also explained in detail.

8.
Sisli Etfal Hastan Tip Bul ; 56(1): 132-136, 2022.
Article in English | MEDLINE | ID: mdl-35515959

ABSTRACT

Objectives: In the present study, we investigated the effects of Vitamin D (vit D) deficiency on aggressiveness of papillary thyroid cancer (PTC). Methods: Patients with PTC confirmed with pathological examination, whom were operated by a single surgeon between 2012 and 2017, were included in the study. The data of the patients were analyzed retrospectively. Cancers other than PTC, patients with hyperthyroidism and/or using antithyroid drugs were excluded from the study. The patients were classified as four quartiles according to serum Vit D levels; category 1 (<7.1 ng/mL), category 2 (7.2-11.8 ng/mL), category 3 (11.9-23.4 ng/mL) and category 4 (>23.5 ng/mL). Results: A total of 133 patients (103 female, 30 male) with mean age of 46.4±13.6 (17-82) years were included in the study. There was no significant difference between the categories in terms of preoperative Vit D values according to the evaluated tumor aggressiveness characteristics. It was determined that the presence of tumor with a size above 1 cm and T3/4 tumor were not affected by Vit D level. There was no significant difference between Vit D categories regarding the characteristics of aggressiveness such as multicentricity, lymphovascular invasion, central, and lateral metastases. Conclusion: According to our results, serum Vit D levels are not associated with the aggressive tumor characteristics of PTC.

9.
Sisli Etfal Hastan Tip Bul ; 56(1): 126-131, 2022.
Article in English | MEDLINE | ID: mdl-35515965

ABSTRACT

Objectives: Thyroid-stimulating hormones (TSHs) are associated with the risk of differentiated thyroid cancer. The relationship between pre-operative TSH levels and aggressive features is unclear. We aimed to evaluate the relationship between pathological features of papillary thyroid carcinoma (PTC) and high TSH levels. Methods: Patients who were operated between 2012 and 2017 and who were found to have PTC in their pathology were included in the study. The relationship between TSH and the features of tumor aggressiveness was evaluated in the patients. Results: Of the 132 patients, TSH level was significantly higher in those with lymphovascular invasion than those without (p=0.048), in those with central metastases than in those without (p=0.014), and in those with extrathyroidal spread than in those without (p=0.003). When patients were categorized into four 25% quartiles according to TSH (mUI/mL) level; the rate of extrathyroidal invasion increased as the TSH level increased, and the level was significantly higher in quartile 1 than the others, with significant difference (p=0.030). Conclusion: Pre-operative increase in TSH level is associated with an increased risk of extrathyroidal spread and central lymph node metastasis. TSH level may be a pre-operative valuable predictive factor for patients' risk of central metastasis.

10.
Sisli Etfal Hastan Tip Bul ; 55(3): 310-317, 2021.
Article in English | MEDLINE | ID: mdl-34712071

ABSTRACT

OBJECTIVE: It is still controversial whether performing central neck dissection (CND) in addition to total thyroidectomy (TT) increases the risk of complications. In the present study, we aimed to evaluate the effect of CND on the development of complications in differentiated thyroid cancer (DTC) compared to TT. MATERIAL AND METHODS: The data of 186 patients (136 females and 50 males) with a mean age of 48.73±14.78 (range, 17-82) whom were operated for DTC were evaluated retrospectively. The patients were divided into two groups; TT (Group 1) and CND±TT/Completion thyroidectomy±lateral neck dissection (Group 2). RESULTS: There were 117 (91 F, 26 M) patients in Group 1 and 69 (45 F, 24 M) patients in Group 2. Parathyroid auto transplantation (PA) was significantly higher in Group 2 compared to Group 1 (42% vs. 6%) (p=0.000). Total (58% vs. 21.4%, respectively; p=0.000) and transient hypoparathyroidism (52.2% vs. 20.5%, respectively; p=0.000) were significantly higher in Group 2 than in Group 1, but permanent hypoparathyroidism rates were statistically not significant (5.8% vs. 0.9%, respectively; p=0.064). In the multinomial logistic regression analysis, CND alone was determined as an independent risk factor for increased both total and transient hypoparathyroidism. The relative risk (RR) of CND for total hypoparathyroidism was 5.2 times increased (odds ratio [OR]: 0.192) (p=0.007), while the RR for transient hypoparathyroidism was 3.5 times increased (OR: 0.285) (p=0.036). According to the number of nerves at risk, CND was performed in 119 neck side and only thyroidectomy was performed in 253 neck side. Total vocal cord paralysis (VCP) rate (9 [7.6%] vs. 6 [2.4%], respectively) (p=0.017) and transient VCP rate (7 [6%] vs. 4 [1.6%], respectively) (p=0.021) in patients who underwent CND were significantly higher compared to those who underwent only thyroidectomy. In multinomial logistic regression analysis performing only CND was an independent risk factor for total VCP, and increased the total VCP RR approximately 5.34 times (OR:0.184; p=0.007). CONCLUSION: Although CND can be applied without increasing the rates of permanent hypoparathyroidism and VCP compared to TT, it increases the risk of total and transient hypoparathyroidism, total, and transient VCP. Patients undergoing CND should be followed carefully in terms of transient hypoparathyroidism.

11.
Sisli Etfal Hastan Tip Bul ; 55(1): 33-41, 2021.
Article in English | MEDLINE | ID: mdl-33935533

ABSTRACT

OBJECTIVES: Hypocalcemia is the most common complication and acute parathyroid gland insufficiency is the main cause of it after thyroidectomy. In this study, we aimed to evaluate the relationship between the recovery time of parathyroid gland function and patient characteristics, preoperative and postoperative electrolyte changes, and intraoperative parathyroid findings in patients with postoperative hypoparathyroidism. METHODS: Patients who underwent total thyroidectomy (TT) with or without central neck dissection ± lateral neck dissection with a parathyroid hormone (PTH) value of <15 pg/mL within the postoperative 4th hour were included in this study. Postoperative calcium level of <8mg/dL was defined as biochemical hypocalcemia and a PTH value of <15 pg/mL was defined as hypoparathyroidism. The patients were divided into three groups according to the time of PTH recovery (>15 pg/mL); within the first 24 hours, between one day and 30 days, after 30 days, respectively. RESULTS: One hundred eleven patients (mean age, 49.3±14.4 years) consisted of Groups 1, 2 and 3, including 19 (16F, 3M), 67 (54F, 13M) and 25 (19F, 6M), respectively. Vitamin D deficiency rates for Groups 1, 2, 3 were 41.7%, 53.1% and 88.2%, respectively (p=0.018). Postoperative day 0 PTH values were 11.69±2.79pg/mL, 6.92±3.45 pg/mL, 4.99±2.36 pg/mL, (p<0.001). Biochemical hypocalcemia rates of Groups 1, 2, 3 on postoperative day 1 were 15.8%, 53.7%, 64%, (p=004) respectively, and calcium values were 8.68±0.67 mg/dL, 8.15±0.66 mg/dL, 7.75±1 mg/dL, (p=0.014), respectively. Magnesium values on postoperative day 1 and 7 for Groups 1, 2, 3 were 1.85±0.1 mg/dL, 1.77±0.17 mg/dL, 1.64±0.17 mg/dL, (p=0.005), and 1.86±0.16mg/dL, 1.82±0.21mg/dL, 1.59±0.15mg/dL (p=0.001), respectively. PTH values on postoperative day 1 and 7 in Groups 1, 2, 3 were 20.5±6.4 pg/mL, 7.06±4.35 pg/mL, 4.66±3.26 pg/mL (p<0.001), and 31.04±10.54pg/mL, 18.72±13.84pg/mL, 4.55±4.9pg/mL (p<0.0001), respectively. Parathyroid function improved in 106 patients, and permanent hypoparathyroidism developed in five patients (4.5%). CONCLUSION: Hypoparathyroidism can recover rapidly in the first 24 hours in patients with a PTH value of around 10 pg/mL at postoperative 4th hour. As the number of preserved parathyroids increased, recovery time decreased. In patients with postoperative hypoparathyroidism, postoperative low magnesium levels may be associated with delayed recovery of parathyroid function.

12.
Sisli Etfal Hastan Tip Bul ; 55(4): 510-515, 2021.
Article in English | MEDLINE | ID: mdl-35317375

ABSTRACT

Objectives: Vitamin D deficiency is a very common global health problem. Evidence from recent studies focuses on the extraskeletal effects of vitamin D (Vit D) deficiency. Chronic lymphocytic thyroiditis (or Hashimoto's thyroiditis) is an autoimmune disease of the thyroid. Although there are many studies reporting that autoimmune thyroid diseases may be associated with Vitamin D deficiency, this is still a controversial issue that has not yet been proven. In this study, we aimed to appraise whether there is a relationship between lymphocytic thyroiditis diagnosed by histopathological evaluation and Vitamin D deficiency. Methods: Data of 256 patients whom were operated by a single surgeon in a single center between 2012 and 2017 and whose preoperative vitamin D tests and thyroid pathologies have been collected, were retrospectively evaluated. Due to the pathological examination, two groups were formed considering the presence of lymphocytic thyroiditis (Group 1), and the absence of lymphocytic thyroiditis (Group 2). Vitamin D deficiency was defined as the level <20 ng/mL (50 nmol/L) and Vitamin D insufficiency was defined as the level 21-29 ng/mL (525-725 nmol/L). Results: There were 108 (92F/16M) patients in Group 1, and 148 (116F/32M) patients in Group 2, and the mean age was lower in Group 1 (p=0.053). The mean vitamin D levels (16.6±15.2 vs. 14±10, p=0.409) and vitamin D deficiency rates (67.6% vs. 72.3%, p=0.416) were found similar between the Groups 1 and 2. No positive significant correlation was found between lymphocytic thyroiditis and vitamin D level or vitamin D deficiency rates. There was a positive correlation between lymphocytic thyroiditis and age, preoperative thyroid-stimulating hormone level, preoperative anti-thyroglobulin ,and anti-thyroid peroxidase levels, but no significant relationship was found with Vitamin D level. Conclusion: According to our results, lymphocytic thyroiditis was not associated with either Vitamin D deficiency or Vitamin D level.

13.
Sisli Etfal Hastan Tip Bul ; 54(4): 451-456, 2020.
Article in English | MEDLINE | ID: mdl-33364886

ABSTRACT

OBJECTIVES: Diverticular disease of the colon is a pathology that arises from outward ballooning of the mucosa due to some weakness in the muscle layer. Diverticular disease may range from symptomatic uncomplicated diverticular disease to symptomatic disease with complications, such as acute diverticulitis or diverticular bleeding. Acute colonic diverticulitis occurs in about 10- 25% of patients. METHODS: In this study, 134 patients who were admitted to our emergency clinic with complaints of abdominal pain between 2016-2019 and hospitalized with the diagnosis of acute diverticulitis were included. Patients' sex, age, presence of additional disease, increase in leukocyte and C-reactive protein (CRP), localization of diverticulitis, Hinchey classification, mean length of hospital stay and treatment were evaluated. The effects of these parameters on complications and recurrence were statistically analyzed. RESULTS: The length of hospital stay was statistically significantly associated positively with the Hinchey classification (p<0.001). While 18 patients who were medically treated developed recurrence later, and this rate was statistically significant (p<0.001). When one of the factors, localization, which may play a role in the severity of the disease and recurrence are examined, was evaluated concerning its results in our study, we found that rectosigmoid location is an important factor for recurrence. We found that the localization in the colon and the severity of the disease were effective in the prognosis of acute diverticulitis. CONCLUSION: We believe that localization and the severity of the disease should be taken into consideration when planning surgery in these patients.

14.
Sisli Etfal Hastan Tip Bul ; 54(4): 469-474, 2020.
Article in English | MEDLINE | ID: mdl-33364889

ABSTRACT

OBJECTIVES: In a thyroidectomy, the external branch of the superior laryngeal nerve (EBSLN) is a potential risk during the superior pole dissection due to its close anatomical relationship with the superior thyroid artery and its highly variable anatomy. In this study, we aimed to evaluate the relationship of EBSLN with the superior pole considering Cernea classification and the factors affecting this relationship. METHODS: The data of thyroidectomized 126 patients (95 female, 31 male) with 200 neck sides (mean age of 45.6±12.1 years) using intraoperative neuromonitoring (IONM) for the EBSLN exploration were evaluated retrospectively. During the superior pole dissection, the EBSLN course was classified according to Cernea classification after being confirmed with IONM. It was defined as a large goiter in the case of the thyroid lobe volume being >50 cc. The factors influencing the presence of type 2b, which has the highest risk of injury, were evaluated using logistic regression analysis. RESULTS: Of the 200 EBSLNs evaluated, 52 (26%) were type 1, 134 (68%) were type 2a, and 14 (7%) were type 2b. The mean volumes of the resected thyroid lobes were 22±25 cc (min-max: 2-136), 23±20 cc (3-163), and 39±24 cc (3-65) in type 1, 2a and 2b, respectively, which was significantly higher in type 2b (p=0.035). Presence of large goiter rates were 5.8% (n=3), 8.2% (n=11), 64.3% (n=9) in type 1, 2a, and 2b, respectively, and was significantly higher in type 2b (p=0.0001). There was no significant difference between EBSLN Cernea types concerning age, sex, nerve side, presence of cancer and hyperthyroidism. In logistic regression analysis, large goiter was the only independent factor associated with Cernea type 2b. In case of a lobe volume greater than 50 cc, the probability of type 2b presence was approximately 25 times higher (p<0.001, odds ratio: 25.262). CONCLUSION: Type 2b course of EBSLN is more common in large goiters, and it is 25 times more likely to be seen in the presence of a lobe volume over 50 cc. Thus, it should be considered that the probability of this high-risk course is significantly higher in large goiters.

15.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 4): 586-589, 2017 Apr 01.
Article in English | MEDLINE | ID: mdl-28435726

ABSTRACT

The asymmetric unit of the title compound, C6H10N22+·2C4HO4-, comprises two hydrogen squarate (Hsq-; systematic name: 2-hy-droxy-3,4-dioxo-cyclo-butano-late) anions and a 2-(aza-niumylmeth-yl)pyridinium dication. The squaric acid mol-ecules each donate an H atom to the N atoms of the pyridine ring and the amino-methyl units of a 2-(amino-meth-yl)pyridine mol-ecule, forming the 1:2 salt. The Hsq- anions are linked by strong O-H⋯O hydrogen bonds and an N-H⋯O hydrogen bond links the 2-(aza-niumylmeth-yl)pyridinium cation to one of the squaric acid anions. The crystal structure features additional N-H⋯O and O-H⋯O hydrogen bonds, π-π stacking and unusual weak C-O⋯π(ring) inter-actions.

16.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 1): 94-6, 2015 Jan 01.
Article in English | MEDLINE | ID: mdl-25705461

ABSTRACT

In the solid state, the title compound, C20H19N3O2, adopts the keto-amine tautomeric form, with the H atom attached to the N atom, which participates in an intra-molecular N-H⋯O hydrogen bond with an S(6) ring motif. The dihedral angles between the pyrazole ring and the phenyl and benzene rings are 3.69 (10) and 46.47 (9)°, respectively. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, generating C(16) chains propagating in [301]. Weak aromatic π-π stacking inter-actions [centroid-centroid distances = 3.6123 (10) and 3.6665 (10) Å] link the chains into a three-dimensional network.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 139: 539-48, 2015 Mar 15.
Article in English | MEDLINE | ID: mdl-25579656

ABSTRACT

A new o-hydroxy Schiff base, (E)-2-[(2-hydroxy-6-methoxybenzylidene)amino]benzonitrile was isolated and investigated by experimental and theoretical methodologies. The solid state molecular structure was determined by X-ray diffraction method. The vibrational spectral analysis was carried out by using FT-IR spectroscopy in the range of 4000-400cm(-)(1). Theoretical calculations were performed by density functional theory (DFT) method using 6-31G(d,p) basis set. The results of the calculations were applied to simulated spectra of the title compound, which show excellent agreement with observed spectra. The UV-vis spectrum of the compound was recorded in the region 200-800 nm in several solvents and electronic properties such as excitation energies, and wavelengths were calculated by TD-DFT/B3LYP method. The most prominent transitions were corresponds to π→π∗. Hybrid density functional theory (DFT) was used to investigate the enol-imine and keto-amine tautomers of titled compound. The titled compound showed the preference of enol form, as supported by X-ray and spectroscopic analysis results. The geometric and molecular properties were compaired for both enol-imine and keto-amine forms. Additionally, geometry optimizations in solvent media were performed with the same level of theory by the integral equation formalism polarizable continuum (IEF-PCM). Stability of the molecule arises from hyperconjugative interactions, charge delocalization and intramolecular hydrogen bond has been analyzed using natural bond orbital (NBO) analysis. Mulliken population method and natural population analysis (NPA) have been studied. Also, condensed Fukui function and relative nucleophilicity indices calculated from charges obtained with orbital charge calculation methods (NPA). Molecular electrostatic potential (MEP) and non linear optical (NLO) properties are also examined.


Subject(s)
Nitriles/chemistry , Nonlinear Dynamics , Optical Phenomena , Schiff Bases/chemistry , Crystallography, X-Ray , Electrons , Hydrogen Bonding , Models, Molecular , Molecular Conformation , Quantum Theory , Solvents/chemistry , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Static Electricity , Stereoisomerism , Vibration
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 128: 748-58, 2014 Jul 15.
Article in English | MEDLINE | ID: mdl-24699294

ABSTRACT

A suitable single crystal of (E)-3-methoxy-2-[(p-tolylimino)methyl]phenol, formulated as C15H15N1O2, reveals that the structure is adopted to its E configuration about the azomethine C=N double bond. The compound adopts a enol-imine tautomeric form with a strong intramolecular O-H⋯N hydrogen bond. The single crystal X-ray diffraction analysis at 296K crystallizes in the monoclinic space group P21/c with a = 13.4791(11) Å, b = 6.8251(3) Å, c = 18.3561(15) Å, α = 90°, ß = 129.296(5)°, γ = 90° and Z = 4. Comprehensive theoretical and experimental structural studies on the molecule have been carried out by FT-IR and UV-vis spectrometry. Optimized molecular structure and harmonic vibrational frequencies have been investigated by DFT/B3LYP method with 6-31G(d,p) basis set. Stability of the molecule, hyperconjugative interactions, charge delocalization and intramolecular hydrogen bond has been analyzed by using natural bond orbital (NBO) analysis. Electronic structures were discussed by TD-DFT method and the relocation of the electron density were determined. The energetic behavior of the title compound has been examined in solvent media using polarizable continuum model (PCM). Molecular electrostatic potential (MEP), Mulliken population method and natural population analysis (NPA) have been studied. Nonlinear optical (NLO) properties were also investigated. In addition, frontier molecular orbitals analysis have been performed from the optimized geometry. An ionization potential (I), electron affinity (A), electrophilicity index (ω), chemical potential (µ), electronegativity (χ), hardness (η), and softness (S), have been investigated.


Subject(s)
Models, Molecular , Phenols/chemistry , Spectrophotometry, Ultraviolet/methods , Spectroscopy, Fourier Transform Infrared/methods , X-Ray Diffraction/methods
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