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1.
J Craniofac Surg ; 34(6): 1650-1654, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36928006

RESUMO

In this study, the authors aimed to share their experience with 46 patients who were wounded due to terrorism and war in Somalia. The authors also evaluated the etiological diversity of terror-related and war-related injuries. The study included 46 patients treated at the 150-bed Turkey-Somalia Tertiary Hospital between 2019 and 2021. The authors reviewed medical records including data regarding age, sex, trauma etiology, and type of fracture and trauma. For all patients, surgical technique and plate and screw applications were recorded. The authors also assessed complications and outcomes for the patients. The study included 5 women (10.9%) and 41 men (89.1%). The mean age was 30.36 years. It was found that 2 patients (4.35%) presented to the emergency department with stab injuries, 33 patients with blast injuries from improvised explosive devices (71.73%), and 11 patients with firearm injuries. There were 31 patients with maxillary and mandibular fractures, 17 of which had both maxillary and mandibular fractures. There were 14 patients with maxillary fracture alone, including 3 patients with tripod fracture and 7 patients with inferior and lateral rim fracture. There was a mandibular fracture in 17 patients, including 5 patients with parasymphysis fracture, 7 patients with ramus fracture, and 5 patients with multifocal comminuted fracture. It is a challenging process to treat terror-related injuries in our tertiary hospital in Somalia, where all resources are imported from foreign countries. In such settings, authorities should make protective equipment obligatory to prevent civil and military casualties. Trauma hospitals and experienced trauma surgeons should be available.


Assuntos
Traumatismos por Explosões , Armas de Fogo , Fraturas Mandibulares , Ferimentos por Arma de Fogo , Masculino , Humanos , Feminino , Adulto , Centros de Atenção Terciária , Fraturas Mandibulares/etiologia , Somália , Ferimentos por Arma de Fogo/cirurgia , Traumatismos por Explosões/diagnóstico , Traumatismos por Explosões/cirurgia , Estudos Retrospectivos
3.
Vascular ; : 17085381221141476, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36441077

RESUMO

OBJECTIVE: To investigate the predictive role of systemic immune-inflammation index (SII) on postoperative poor outcome in patients undergoing carotid endarterectomy (CEA). METHODS: A total of 347 patients undergoing elective isolated CEA between March 2010 and April 2022 were included in this multicenter retrospective observational cohort and risk-prediction study and were divided into two groups as poor outcome group (n = 23) and favorable outcome group (n = 324). Poor outcome was defined as the presence of at least one of the complications within 30 days of surgery including stroke, myocardial infarction, and death. The patients' baseline clinical characteristics, comorbidities, and hematological indices were derived from the complete blood count (CBC) analysis, and perioperative data, outcomes, and complications were screened, recorded, and then compared between the groups. Multivariate logistic regression and receiver-operating characteristic (ROC) curve analyses were conducted following univariate analyses to detect the independent predictors of poor outcome as well as the cutoff values with sensitivity and specificity rates. RESULTS: A total of 23 patients out of 347 (6.6%) manifested poor outcome; and stroke, myocardial infarction, and death occurred in 13, 3, and 7 cases, respectively. There were no significant differences between the groups in terms of basic clinical characteristics, comorbidities, and perioperative data, except for lengths of intensive care unit and hospital stays. Although the median values of PLT, PLR, NLR, and SII of the poor outcome group were found to be significantly higher than the favorable outcome group in univariate analysis, only SII was detected to be a significant and independent predictor of poor outcome in multivariate logistic regression analysis (OR = 1.0008; 95% CI: 1.0004-1.0012; p = 0.002). ROC curve analysis revealed that SII of 1356 × 103/mm3 constituted the cutoff value for predicting poor outcome with 78.3% sensitivity and 64.5% specificity (AUC = 0.746; 95% CI: 0.64-0.851). CONCLUSIONS: Our study revealed for the first time in the literature that SII significantly predicted poor outcome after CEA.

4.
Rev Assoc Med Bras (1992) ; 68(12): 1747-1752, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36449805

RESUMO

OBJECTIVE: This study aimed to investigate the effect of preoperative pulmonary hypertension (PHT) on postoperative early mortality and morbidity in patients undergoing off-pump coronary artery bypass grafting (CABG). METHODS: A total of 1107 patients undergoing elective first-time off-pump CABG between January 2011 and April 2022 were included in this retrospective observational cohort study. The patients were categorized into two groups according to their preoperative systolic pulmonary artery pressure (SPAP) values. The PHT group (n=104) consisted of patients with a SPAP value >30 mmHg, while the non-PHT group (n=1003) consisted of patients with a SPAP value ≤30 mmHg. Patients' preoperative demographics and clinical features, operative data, and postoperative outcomes were recorded and then compared between the groups. RESULTS: In the PHT group, the median age was significantly higher (66 vs. 63 years, p=0.001) and the median left ventricular ejection fraction level was significantly lower (45 vs. 50%, p=0.045) as compared to the non-PHT group. Additionally, the PHT group included a significantly greater percentage of patients with chronic obstructive pulmonary disease (22.1 vs. 7.4%, p=0.019). As perioperative early-term outcomes, complications, and mortality were considered, the groups were statistically similar, and there were no significant differences between the groups, except for the development of atrial fibrillation. CONCLUSION: For the first time in the literature, this study revealed that mild PHT (mean SPAP=38.9±8.7 mmHg) did not significantly affect early-term outcomes of off-pump CABG.


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Doença da Artéria Coronariana , Hipertensão Pulmonar , Humanos , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Ponte de Artéria Coronária , Hipertensão Pulmonar/complicações , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda , Complicações Pós-Operatórias , Resultado do Tratamento , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/cirurgia
5.
Rev Assoc Med Bras (1992) ; 68(9): 1240-1246, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36228255

RESUMO

OBJECTIVE: This study aims to examine the predictive role of systemic immune-inflammation index on postoperative new-onset atrial fibrillation in patients undergoing off-pump coronary artery bypass grafting. METHODS: A total of 722 patients undergoing elective off-pump coronary artery bypass grafting between January 2017 and September 2021 were included in this study and divided into two groups as the atrial fibrillation group (n=172) and the non-atrial fibrillation group (n=550). Both groups were compared in terms of patients' baseline clinical features, operative and postoperative variables, and preoperative hematological indices derived from the complete blood count analysis. Multivariate logistic regression and receiver-operating characteristic curve analyses were performed to detect the independent predictors of postoperative new-onset atrial fibrillation. RESULTS: The median age and length of hospital stay in the atrial fibrillation group were significantly higher than those in the non-atrial fibrillation group. The median values of white blood cell, platelet, neutrophil, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, and systemic immune-inflammation in the atrial fibrillation group were significantly greater than in those in the non- atrial fibrillation group. Logistic regression analysis demonstrated that age, platelet, platelet/lymphocyte ratio, and systemic immune-inflammation were independent predictors of postoperative new-onset atrial fibrillation. receiver-operating characteristic curve analysis revealed that systemic immune-inflammation of 706.7×103/mm3 constituted cut-off value to predict the occurrence of new-onset atrial fibrillation with 86.6% sensitivity and 29.3% specificity. CONCLUSION: Our study revealed for the first time that systemic immune-inflammation predicted new-onset atrial fibrillation after off-pump coronary artery bypass grafting.


Assuntos
Fibrilação Atrial , Ponte de Artéria Coronária sem Circulação Extracorpórea , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/etiologia , Ponte de Artéria Coronária , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Humanos , Inflamação/etiologia , Tempo de Internação , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fatores de Risco
6.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 68(9): 1240-1246, Sept. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1406659

RESUMO

SUMMARY OBJECTIVE: This study aims to examine the predictive role of systemic immune-inflammation index on postoperative new-onset atrial fibrillation in patients undergoing off-pump coronary artery bypass grafting. METHODS: A total of 722 patients undergoing elective off-pump coronary artery bypass grafting between January 2017 and September 2021 were included in this study and divided into two groups as the atrial fibrillation group (n=172) and the non-atrial fibrillation group (n=550). Both groups were compared in terms of patients' baseline clinical features, operative and postoperative variables, and preoperative hematological indices derived from the complete blood count analysis. Multivariate logistic regression and receiver-operating characteristic curve analyses were performed to detect the independent predictors of postoperative new-onset atrial fibrillation. RESULTS: The median age and length of hospital stay in the atrial fibrillation group were significantly higher than those in the non-atrial fibrillation group. The median values of white blood cell, platelet, neutrophil, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, and systemic immune-inflammation in the atrial fibrillation group were significantly greater than in those in the non- atrial fibrillation group. Logistic regression analysis demonstrated that age, platelet, platelet/lymphocyte ratio, and systemic immune-inflammation were independent predictors of postoperative new-onset atrial fibrillation. receiver-operating characteristic curve analysis revealed that systemic immune-inflammation of 706.7×103/mm3 constituted cut-off value to predict the occurrence of new-onset atrial fibrillation with 86.6% sensitivity and 29.3% specificity. CONCLUSION: Our study revealed for the first time that systemic immune-inflammation predicted new-onset atrial fibrillation after off-pump coronary artery bypass grafting.

7.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 68(12): 1747-1752, 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1422549

RESUMO

SUMMARY OBJECTIVE: This study aimed to investigate the effect of preoperative pulmonary hypertension (PHT) on postoperative early mortality and morbidity in patients undergoing off-pump coronary artery bypass grafting (CABG). METHODS: A total of 1107 patients undergoing elective first-time off-pump CABG between January 2011 and April 2022 were included in this retrospective observational cohort study. The patients were categorized into two groups according to their preoperative systolic pulmonary artery pressure (SPAP) values. The PHT group (n=104) consisted of patients with a SPAP value >30 mmHg, while the non-PHT group (n=1003) consisted of patients with a SPAP value ≤30 mmHg. Patients' preoperative demographics and clinical features, operative data, and postoperative outcomes were recorded and then compared between the groups. RESULTS: In the PHT group, the median age was significantly higher (66 vs. 63 years, p=0.001) and the median left ventricular ejection fraction level was significantly lower (45 vs. 50%, p=0.045) as compared to the non-PHT group. Additionally, the PHT group included a significantly greater percentage of patients with chronic obstructive pulmonary disease (22.1 vs. 7.4%, p=0.019). As perioperative early-term outcomes, complications, and mortality were considered, the groups were statistically similar, and there were no significant differences between the groups, except for the development of atrial fibrillation. CONCLUSION: For the first time in the literature, this study revealed that mild PHT (mean SPAP=38.9±8.7 mmHg) did not significantly affect early-term outcomes of off-pump CABG.

8.
Sao Paulo Med J ; 139(3): 279-284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076230

RESUMO

BACKGROUND: Vitamin D has relationships with pathogenesis and inflammation pathways in many diseases. Its deficiency may make clinicians think not only of supplementation but also of presence of other diseases. OBJECTIVE: To investigate the relationship between vitamin D levels and deep vein thrombosis (DVT), given that reduced levels are related to increased risk of cardiovascular diseases. DESIGN AND SETTING: Case-control study conducted in the cardiovascular surgery and family medicine departments of a hospital in Turkey. METHODS: A total of 280 participants were included: 140 each in the DVT and control groups. Basic clinical characteristics, comorbidities and serum 25-hydroxyvitamin D (25(OH)D) levels were recorded and then compared between the groups. Serum 25(OH)D levels were also evaluated separately in three subgroups (sufficient, insufficient and deficient). RESULTS: Serum 25(OH)D levels were significantly lower in the DVT group than in the controls (P < 0.001). Females in the DVT group had lower 25(OH)D levels than those in the control group (P = 0.002). Nonetheless, the median 25(OH)D level (16.41 ng/ml) of the control group was still below the reference value. Logistic regression analysis showed that 25(OH)D was a significant predictor of DVT. Weight, height and body mass index, which all presented interaction, were significant in the logistic regression analysis but not in individual analyses. CONCLUSION: The serum vitamin D levels of DVT patients were lower than those of controls. If the results obtained from our study are supported by further large-scale randomized controlled trials, vitamin D replacement may be brought into the agenda for protection against DVT.


Assuntos
Trombose Venosa , Deficiência de Vitamina D , Vitamina D/sangue , Estudos de Casos e Controles , Extremidades , Feminino , Humanos , Masculino , Turquia , Trombose Venosa/etiologia , Deficiência de Vitamina D/complicações
9.
São Paulo med. j ; 139(3): 279-284, May-June 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1252247

RESUMO

ABSTRACT BACKGROUND: Vitamin D has relationships with pathogenesis and inflammation pathways in many diseases. Its deficiency may make clinicians think not only of supplementation but also of presence of other diseases. OBJECTIVE: To investigate the relationship between vitamin D levels and deep vein thrombosis (DVT), given that reduced levels are related to increased risk of cardiovascular diseases. DESIGN AND SETTING: Case-control study conducted in the cardiovascular surgery and family medicine departments of a hospital in Turkey. METHODS: A total of 280 participants were included: 140 each in the DVT and control groups. Basic clinical characteristics, comorbidities and serum 25-hydroxyvitamin D (25(OH)D) levels were recorded and then compared between the groups. Serum 25(OH)D levels were also evaluated separately in three subgroups (sufficient, insufficient and deficient). RESULTS: Serum 25(OH)D levels were significantly lower in the DVT group than in the controls (P < 0.001). Females in the DVT group had lower 25(OH)D levels than those in the control group (P = 0.002). Nonetheless, the median 25(OH)D level (16.41 ng/ml) of the control group was still below the reference value. Logistic regression analysis showed that 25(OH)D was a significant predictor of DVT. Weight, height and body mass index, which all presented interaction, were significant in the logistic regression analysis but not in individual analyses. CONCLUSION: The serum vitamin D levels of DVT patients were lower than those of controls. If the results obtained from our study are supported by further large-scale randomized controlled trials, vitamin D replacement may be brought into the agenda for protection against DVT.


Assuntos
Humanos , Masculino , Feminino , Vitamina D/sangue , Deficiência de Vitamina D/complicações , Trombose Venosa/etiologia , Turquia , Estudos de Casos e Controles , Extremidades
10.
Vascular ; 29(2): 248-255, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32772842

RESUMO

OBJECTIVE: To examine dynamic thiol/disulphide homeostasis metrics as a novel risk factor of oxidative stress in patients with peripheral arterial disease. METHODS: One hundred patients with lower extremity peripheral arterial disease (a study group) and 100 control subjects were included in this prospective case-control study. Participants' baseline clinical characteristics and laboratory data including some oxidant/antioxidant status parameters such as albumin, ferroxidase and myeloperoxidase, and thiol/disulphide homeostasis parameters such as native thiol, total thiol and disulphide, as well as native thiol/total thiol, disulphide/native thiol and disulphide/total thiol ratios were all recorded and then compared between the groups. RESULTS: Mean albumin and ferroxidase, and median myeloperoxidase levels were found to be significantly higher in patients with the peripheral arterial disease than in control group (p = 0.045, p = 0.000 and p = 0.000, respectively). Mean native thiol and total thiol, and median disulphide levels were found to be significantly lower in the study group as compared with the control group (p = 0.000, p = 0.000 and p = 0.037, respectively). According to the results of logistic regression analysis, systolic blood pressure, ferroxidase and myeloperoxidase levels were detected to be the independent predictors of peripheral arterial disease. CONCLUSION: Our report is the first one in the literature investigating dynamic thiol/disulphide homeostasis metrics as a novel risk factor of oxidative stress in peripheral arterial disease. Dynamic thiol/disulphide homeostasis metrics may be used as a valuable risk factor of oxidative stress in patients with the peripheral arterial disease since it is readily available, easily calculated and relatively cheap.


Assuntos
Dissulfetos/sangue , Estresse Oxidativo , Doença Arterial Periférica/sangue , Compostos de Sulfidrila/sangue , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Homeostase , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Fatores de Risco
11.
Heart Surg Forum ; 22(5): E416-E422, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31596723

RESUMO

BACKGROUND: Olfactory and taste sensations have a high impact on the quality of life. Impaired olfactory and taste functions may have a negative effect on physical and mental well-being, personal hygiene, and nutritional satisfaction, leading to the occurrence of depressive symptoms and impaired quality of life. Therefore, the recovery period of patients with disturbed olfactory and taste functions may be prolonged, and return to active life may be delayed. We designed this study to determine whether on-pump and off-pump coronary artery bypass grafting (CABG) surgeries have any effects on olfactory and taste functions and compare these functions between the surgical groups. METHODS: A total of 60 patients, who underwent elective isolated first-time CABG, were included in this study. Patients were divided into two groups as Off-Pump and On-Pump CABG groups with 30 patients in each group. In addition to patients' primary clinical and laboratory data, olfactory and taste functions were evaluated pre- and postoperatively in both groups separately, and then these functions were compared between the groups. Olfactory functions were evaluated by the Brief Smell Identification Test, while taste functions by the Burghart Taste test. RESULTS: Olfactory functions significantly were disrupted in the postoperative period in patients undergoing on-pump CABG (P value < .05), while these functions significantly were not affected in patients undergoing off-pump CABG (P value > .05). During the preoperative period, advanced age and smoking were detected to be independent predictors of impaired olfactory function for the study population. During the postoperative period, smoking, amount of postoperative bleeding and serum low-density lipoprotein (LDL) level were found to be independent predictors of impaired olfactory function for just the On-Pump CABG Group. In both groups, no significant deterioration in taste functions occurred during the postoperative period (P value > .05). CONCLUSION: Our study demonstrated that olfactory function was impaired in patients, who underwent on-pump CABG in the postoperative period, and significant impairment in taste function was present in neither off-pump nor on-pump CABG patients. However, the results of our study should be supported by more comprehensive, prospective, randomized controlled trials with more extensive patient series and by further tests.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Transtornos do Olfato/etiologia , Complicações Pós-Operatórias/etiologia , Distúrbios do Paladar/etiologia , Fatores Etários , Idoso , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Complicações do Diabetes , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Feminino , Humanos , Lipoproteínas LDL/sangue , Masculino , Hemorragia Pós-Operatória/complicações , Olfato , Fumar/efeitos adversos , Paladar
12.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 4): 586-589, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28435726

RESUMO

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.

13.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 7): 998-1001, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27555949

RESUMO

In the title inner salt molecule, C10H10N2O3, the four-membered cyclobutene ring is twisted by 7.1 (2)° with respect to the five-membered imidazole ring. The crystal packing exhibits an R 2 (2)(9) hydrogen-bonding ring motif through N-H⋯O and C-H⋯O inter-actions. The potential non-linear optical properties were studied by a computational ab initio calculations performed at the DFT/B3LYP/6-31++G(d,p) level of theory.

14.
Artigo em Inglês | MEDLINE | ID: mdl-25590828

RESUMO

The detailed investigation of an organic nonlinear optical (NLO) squarate salt of 3-phenylpyridinium hydrogen squarate (1), C11H10N+·C4HO4(-), was reported in this study. The XRD data indicates that the crystal structure of the title compound is in the triclinic P-1 space group. In the asymmetric unit, the 3-phenylpyridine molecule is protonated by one hydrogen atom donation of squaric acid molecule, forming the salt (1). The X-ray analysis shows that the crystal packing has hydrogen bonding ring pattern of D2(2)(10) (α-dimer) through NH···O interactions. The structural and vibrational properties of the compound were also studied by computational methods of ab initio at DFT/B3LYP/6-31++G(d,p) (2) and HF/6-31++G(d,p) (3) levels of theory. The calculation results on the basis of two models for both the optimized molecular structure and vibrational properties for the 1 are presented and compared with the experimental results. Non-linear optical properties (NLO) of the title compound together with the molecular electrostatic potential (MEP), electronic absorption spectrum, frontier molecular orbitals (FMOs) and conformational flexibility were also studied at the 2 level and the results were reported. In order to evaluate the suitability for NLO applications thermal analysis (TG, DTA and DTG) data of 1 were also obtained.


Assuntos
Ciclobutanos/química , Piridinas/química , Cristalografia por Raios X , Dimerização , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt B: 1058-68, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25459503

RESUMO

The experimental and theoretical investigation of a novel organic nonlinear optical (NLO) squarate salt of 2-pyridinium propanol hydrogen squarate (1), C8H12ON(+)·C4HO4(-), were reported in this study. The crystal structure of the title compound was found to crystallize in the triclinic P-1 space group. In the asymmetric unit each squaric acid molecules have donated one H atom to the pyridines N1 and N2 atoms of a 2-pyridine propanol molecule, forming the salt (1). The X-ray analysis clearly indicated that the crystal packing has shown the hydrogen bonding ring pattern of D2(2)(10) (α-dimer) through N-H⋯O interactions. The structural and vibrational properties of the compound were also studied by computational methods of ab initio performed on the compound at DFT/B3LYP/6-31++G(d,p) (2) and HF/6-31++G(d,p) (3) level of theory. The calculation results on the basis of two models for both the optimized molecular structure and vibrational properties for the 1 are presented and compared with the X-ray analysis result. The molecular electrostatic potential (MEP), electronic absorption spectra, frontier molecular orbitals (FMOs), conformational flexibility and non-linear optical properties (NLO) of the title compound were also studied at the 2 level and the results are reported. In order to evaluate the suitability for NLO applications thermal analysis (TG, DTA and DTG) data of 1 were also obtained.


Assuntos
Ciclobutanos/química , Modelos Moleculares , Dinâmica não Linear , Fenômenos Ópticos , Propanóis/química , Compostos de Piridínio/química , Cristalografia por Raios X , Análise Diferencial Térmica , Elétrons , Ligação de Hidrogênio , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria , Vibração
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 134: 233-43, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25022494

RESUMO

The experimental and theoretical investigation results of a novel organic squarate salt of 4-Morpholinium bis(hydrogen squarate) (1), C6H14ON(+)·C8H3O8(-), were reported in this study. The crystal structure of the title compound was found to crystallize in the triclinic P-1 space group. In the crystals of 1 the morpholine ring adopts the chair conformation with the ethyl group in the equatorial and hydrogen atoms in axial positions. The hydrogen squarate anions are linked into a homoconjugated anion, [(HSQ)2H], by a short symmetric, nonlinear O8⋯H2⋯O2 hydrogen bond of 2.444 (2)Å. The structural and vibrational properties of the compound were also studied by computational methods of ab-initio performed on the compound at DFT/B3LYP/6-31++G(d,p) (2) and HF/6-31++G(d,p) (3) level of theory. The obtained calculation results on the basis of two models for both the optimized molecular structure and vibrational properties for the 1 obtained are presented and compared with the X-ray analysis result. On the other hand the molecular electrostatic potential (MEP), electronic absorption spectra, frontier molecular orbitals (FMOs), conformational flexibility and non-linear optical properties (NLO) of the title compound were also studied at the 2 level and the results are reported. In order to evaluate the suitability for NLO applications thermal analysis (TG, DTA and DTG) data of 1 were also obtained.


Assuntos
Ciclobutanos/química , Morfolinas/química , Teoria Quântica , Técnicas de Química Sintética , Cristalografia por Raios X , Ciclobutanos/síntese química , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Morfolinas/síntese química , Prótons , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 130: 376-85, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24813271

RESUMO

The experimental and theoretical investigation results of a novel organic non-linear optical (NLO) organic squarate salt of 2-Picolinium hydrogensquarate (1), C6H8N+·C4HO4-, were reported in this study. The space group of the title compound was found in the monoclinic C2/c space group. It was found that the asymmetric unit consists of one monohydrogen squarate anion together with mono protonated 2-Picolinium, forming the (1) salt. The X-ray analysis clearly indicated that the crystal packing has shown the hydrogen bonding ring pattern of D2(2)(10) (α-dimer) through NH⋯O interactions. The hydrogensquarate anions form α-dimer, while 2-Picolinium molecule interacts through NH⋯O and CH⋯O with the hydrogensquarate anion. The structural and vibrational properties of the compound were also studied by computational methods of ab initio performed on the compound at DFT/B3LYP/6-31++G(d,p) (2) and HF/6-31++G(d,p) (3) level of theory. The calculation results on the basis of two models for both the optimized molecular structure and vibrational properties for the 1 obtained are presented and compared with the X-ray analysis result. On the other the molecular electrostatic potential (MEP), electronic absorption spectra, frontier molecular orbitals (FMOs), conformational flexibility and non-linear optical properties (NLO) of the title compound were also studied at the 2 level and the results are reported. In order to evaluate the suitability for NLO applications thermal analysis (TG, DTA and DTG) data of 1 were also obtained.


Assuntos
Ciclobutanos/química , Hidrogênio/química , Picolinas/química , Ânions , Cristalização , Ciclobutanos/síntese química , Dimerização , Ligação de Hidrogênio , Conformação Molecular , Nitrogênio/química , Óptica e Fotônica , Picolinas/síntese química , Teoria Quântica , Software , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Temperatura , Difração de Raios X
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