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OBJECTIVE: Primary hypophysitis might be challenging to diagnose, and there is a lack of evidence regarding optimal treatment strategies due to rarity of the disease. We aim to investigate the clinical features and compare the outcomes of different management strategies of primary hypophysitis in a large group of patients recruited on a nationwide basis. DESIGN: A retrospective observational study. METHODS: The demographic, clinical, radiologic features, and follow-up data were collected in study protocol templates and analyzed. RESULTS: 113 patients (78.8% female, median age: 36 years) were included. Lymphocytic (46.7%) and granulomatous hypophysitis (35.6%) were the prevailing subtypes out of 45 patients diagnosed after pathologic investigations. Headache (75.8%) was the most common symptom, and central hypogonadism (49.5%) the most common hormone insufficiency. 52.2% of the patients were clinically observed without interventions, 18.6% were started on glucocorticoid therapy, and 29.2% underwent surgery at presentation. Headache, suprasellar extension, and chiasma compression were more common among glucocorticoid-treated patients than observed. Cox regression analysis revealed higher hormonal and radiologic improvement rates in the glucocorticoid-treated group than observation group (HR, 4.60; 95% CI, 1.62-12.84 and HR, 3.1; 95% CI, 1.40-6.68, respectively). The main indication for surgery was the inability to exclude a pituitary adenoma in the presence of compression symptoms, with a recurrence rate of 9%. CONCLUSION: The rate of spontaneous improvement might justify observation in mild cases. Glucocorticoids proved superior to observation in terms of hormonal and radiologic improvements. Surgery may not be curative, and might be considered in indeterminate, treatment-resistant or severe cases.
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PURPOSE: The quality of radiotherapy auto-segmentation training data, primarily derived from clinician observers, is of utmost importance. However, the factors influencing the quality of clinician-derived segmentations are poorly understood; our study aims to quantify these factors. METHODS: Organ at risk (OAR) and tumor-related segmentations provided by radiation oncologists from the Contouring Collaborative for Consensus in Radiation Oncology data set were used. Segmentations were derived from five disease sites: breast, sarcoma, head and neck (H&N), gynecologic (GYN), and GI. Segmentation quality was determined on a structure-by-structure basis by comparing the observer segmentations with an expert-derived consensus, which served as a reference standard benchmark. The Dice similarity coefficient (DSC) was primarily used as a metric for the comparisons. DSC was stratified into binary groups on the basis of structure-specific expert-derived interobserver variability (IOV) cutoffs. Generalized linear mixed-effects models using Bayesian estimation were used to investigate the association between demographic variables and the binarized DSC for each disease site. Variables with a highest density interval excluding zero were considered to substantially affect the outcome measure. RESULTS: Five hundred seventy-four, 110, 452, 112, and 48 segmentations were used for the breast, sarcoma, H&N, GYN, and GI cases, respectively. The median percentage of segmentations that crossed the expert DSC IOV cutoff when stratified by structure type was 55% and 31% for OARs and tumors, respectively. Regression analysis revealed that the structure being tumor-related had a substantial negative impact on binarized DSC for the breast, sarcoma, H&N, and GI cases. There were no recurring relationships between segmentation quality and demographic variables across the cases, with most variables demonstrating large standard deviations. CONCLUSION: Our study highlights substantial uncertainty surrounding conventionally presumed factors influencing segmentation quality relative to benchmarks.
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Teorema de Bayes , Benchmarking , Radio-Oncologistas , Humanos , Benchmarking/métodos , Feminino , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias/epidemiologia , Neoplasias/radioterapia , Órgãos em Risco , Masculino , Radioterapia (Especialidade)/normas , Radioterapia (Especialidade)/métodos , Demografia , Variações Dependentes do ObservadorRESUMO
Copper metal is third most abundant trace element in human body. Determination of Cu (II) ions is a burning topic in field of environment protection and food safety because of its significant impact on ecosystem. In this study, 2,6-pyridine dicarboxylic acid (PDA) has been explored as "turn-off" florescent probe for florescent detection of Cu (II) ions. This sensor showed highly selective complexing ability towards Cu (II) ions. Addition of aqueous solution of Cu (II) ions remarkably quenched the fluorescence intensity of PDA while, on contrary, there was no any prominent fluorescence quenching interference on addition of various metal ions. The binding mode of PDA and Cu (II) ions was determined as stoichiometry of 1:1 and it was further confirmed by single crystal XRD analysis. Mechanisms of static and dynamic quenching were confirmed by stern-volmer plot. Limit of detection (LOD) and limit of quantification (LOQ) for Cu (II) ions was calculated as 3.6 µM and 1.23 µM respectively, which is far below the acceptable value (31.5µM) according to the World Health Organization. The use of the sensor for detection of Cu (II) ions in real samples in aqueous media was also performed.
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One of the most important steps in zygomatic implant surgery is to determine the implant length. This cadaver study aims to identify an alternative technique for determining the length of the implant in zygoma surgery without excessive elevation of the flap. A total of 30 cadavers were included in this study. Measurements were made with a probe by seeing the exit point of the drills from the lateral aspect of the zygomatic bone. Secondly, without excessive flap release, the distance that the depth probe first raises the skin over the lateral border of the zygoma is measured. The average difference between the measurements made without excessive elevation of the flap and with a retractor placed on the zygomaticofrontal notch was found to be 5.41 ± 0.94 mm (range: 5-7.5 mm). According to the results of this study, the zygomatic implant should be placed at least 5 mm shorter than the length at which the depth probe first raises the skin over the lateral border of the zygomatic bone.
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In this work, we report on the synthesis of a novel zinc(II) coordination compound [ZnL2] (1), which was readily obtained from the reaction of Zn(OAc)·2H2O and N'-(pyridin-2-ylmethylene)nicotinohydrazide (HL) in methanol. Recrystallization of 1 from dimethylformamide under ambient conditions allowed to produce yellow block-like crystals of 1·H2O. Complex 1·H2O was characterized by FT-IR and 1H NMR spectroscopy, while its optical properties were studied by UV-vis and spectrofluorimetry in methanol. The crystal structure of the title complex was revealed by single crystal X-ray diffraction and further explored in detail by the Hirshfeld surface analysis. Theoretical investigations based on the DFT calculations have also been applied to show the electronic properties of complex 1. The antitumor activities of the parent ligand HL and complex 1 were studied using Dalton's lymphoma malignant cancer model. Both compounds were found to induce concentration-dependent cytotoxicity and apoptotic cell death, leading to a decrease in cell viability, body weight, and tumor volume in mice with the superior activity of complex 1 over HL. Mice treated with complex 1 demonstrated an increase in life span with a survival period of 23 days. Finally, using a molecular docking approach, we have probed complex 1 to inhibit the recombinant mouse tumor-necrosis factor alpha (mTNF).
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Antineoplásicos , Complexos de Coordenação , Zinco , Zinco/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Animais , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Humanos , Cristalografia por Raios X , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacosRESUMO
The number of implants and their respective configurations for implant-supported treatment modalities have been studied for 4 implant-supported prostheses; however, it is not yet clear whether the use of tilting or short implants in rehabilitation would result in substantially improved bone/implant/prosthesis biomechanics in all-on-six concepts. This study compared the biomechanical behavior of tilted long implants and axially short implants to support fixed prostheses in an atrophic maxilla with all-on-six treatment concepts. Three different implant configurations were planned, and six models were obtained with posterior maxilla D3 and D4 bone densities in this study. Implants proper for the all-on-four concept were placed in all models. In models 1 and 2, the short implant was placed; in models 3 and 4, 30°, the mesial-angled implant was placed; and in models 5 and 6, 45°, the mesial-angled implant was placed to the molar region. In the models created, 200 N vertical and 150 N oblique (45° angled buccopalatal direction) forces were implemented to the bilateral tooth regions 4-5-6 on the rigid titanium-supported fixed hybrid prosthesis made on these models. When the stress values in the models were investigated, the oblique forces had higher stress values than the vertical forces did. When the stresses created by oblique forces were assessed, the highest values were observed in the models created with short implants, and the lowest stress values were observed in the models made with 30° angle to mesial. When bone densities were assessed, more stress values were noted in models with D4 bone density. It has been shown that mesial tilted long implants placed in the posterior molar region, in addition to all four implant treatment concepts, create less stress against undesirable oblique forces compared with short implants.
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Implantes Dentários , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Análise do Estresse Dentário , Análise de Elementos Finitos , Humanos , Fenômenos Biomecânicos , Maxila/cirurgia , Estresse Mecânico , Densidade Óssea , Implantação Dentária Endóssea/métodosRESUMO
Depression is a common psychiatric disorder among individuals with Huntington's disease (HD). Depression in HD and major depressive disorder appear to have different pathophysiological mechanisms. Despite the unique pathophysiology, the treatment of depression in HD is based on data from the treatment of major depressive disorder in the general population. The objective of this systematic review was to conduct a comprehensive evaluation of the available evidence. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Studies on the treatment of depression in HD were identified by searching MEDLINE, Embase, and PsycInfo. The initial search yielded 2,771 records, 41 of which were ultimately included. There were 19 case reports, seven case series, three cross-sectional studies, one qualitative study, nine nonrandomized studies, and two randomized trials among the included studies. The most common assessment tools were the Hospital Anxiety and Depression Scale (N=8), the Beck Depression Inventory (N=6), and the Hamilton Depression Rating Scale (N=6). Only 59% of the included studies assessed depressive symptoms with a scoring system. The pharmacological options for the treatment of depression included antidepressants and antipsychotics. Nonpharmacological approaches were multidisciplinary rehabilitation, psychotherapy, and neurostimulation. Limited evidence on the treatment of depression in HD was available, and this literature consisted mainly of case reports and case series. This systematic review highlights the knowledge gap and the pressing need for HD-specific research to determine the efficacy of treatment approaches for depression in HD.
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INTRODUCTION: Well-differentiated neuroendocrine tumors of the appendix (A-WDNET) are the most common neoplasms of the appendix but are rare and incidental. INSM1 is a novel transcription factor marker with high sensitivity and specificity for neuroendocrine differentiation. It may display architecturally diverse tumor growth patterns including solid, nest, insular trabecular, and acinar. AIMS: The aim of this study was to determine the staining expression of INSM1 in A-WDNETs and detail the morphological tumor growth patterns. MATERIALS AND METHODS: INSM1 immunohistochemistry was performed on 35 A-WDNET patients. Tumors were histologically classified according to their growth patterns. RESULTS: Thirty-five patients, 60% of whom were male, had a mean age of 30 years at diagnosis and a mean tumor size of 0.9 cm. Eight percent of the tumors invaded the mucosa/submucosa, 34.3% showed invasion into the muscularis propria, 57.1% showed invasion into the subserosa or mesoappendix, LN metastasis was observed in two patients, lymph-vascular invasion in two patients, and perineural invasion in five patients. Ninety-four percent of the tumors were grade 1, the mitotic rate was >2% in two cases, and Ki-67 PI was >3% in two cases. INSM1 was positive in all cases (100%), 1+ 8.6%, 2+ 5.7%, 3+ 17.1%, 4+ 68.6%, weak staining in 11.4%, moderate staining in 22.9%, and strong staining in 67.7%. Type A histological growth pattern was observed in 54.3%, type B in 31.4%, and type C in 14.3% architecturally. CONCLUSIONS: INSM1 was positive in all A-WDNET morphological patterns and was 100% sensitive. INSM1 IHC can be used as an alternative to traditional neuroendocrine markers or in combination with the diagnosis of neuroendocrine tumors.
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Neoplasias do Apêndice , Biomarcadores Tumorais , Imuno-Histoquímica , Tumores Neuroendócrinos , Proteínas Repressoras , Humanos , Masculino , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/diagnóstico , Feminino , Adulto , Proteínas Repressoras/genética , Pessoa de Meia-Idade , Neoplasias do Apêndice/patologia , Adulto Jovem , Adolescente , Centros de Atenção Terciária , Apêndice/patologia , IdosoRESUMO
A Rhodamine B-Zn-MOF composite (RhB-Zn-MOF) with dual emission intensity was synthesized through one pot synthesis by in-situ encapsulation of Rhodamine-B dye on a new Zn-MOF metal-organic framework [(Zn(OAc)2(4-BrIPh) (1,10-phenonthroline)(H2O)].H2O, (4-BrIPh = 4-Bromoisophthalic acid). The synthesized encapsulated material was characterized by elemental analysis, FTIR, UV-Visible spectroscopy, TGA, single crystal and powder X-ray diffraction and photoluminescence spectroscopy. The results showed that the synthesized composite, RhB-Zn-MOF could be used as an efficient probe for the selective sensing of Cr(VI) in the presence of Cr(III) as well as other metal ions.
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We have developed a new scaffold that exhibits an efficient intramolecular through-space charge transfer (CT). In this design, electron-rich benzofuran and electron-deficient ynone groups are placed strategically in proximity via a naphthalene spacer. Charge transfer is supported by distinct CT bands in the visible region (>500 nm) in their UV-vis absorption and emission spectra.
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PURPOSE: In our study, our aim was to investigate the role of [68 Ga]Ga-PSMA-11 PET /CT imaging in the diagnosis of clinically significant prostate cancer (csPCa) (ISUP GG 2 and higher) in patients initially diagnosed with ISUP GG 1 and 2 after prostate biopsy. MATERIALS AND METHODS: We retrospectively reviewed 147 patient records in whom [68 Ga]Ga-PSMA-11 PET/CT imaging was performed preoperatively. All patients were initially diagnosed with ISUP GG 1 and 2 PCa by biopsy. Final pathology reports were obtained after radical prostatectomy. The [68 Ga]Ga-PSMA-11 PET/CT images were evaluated to determine the PRIMARY score. Patients' mpMRI-PIRADS scores were also recorded when available and analyzed in correlation with the pathology results. RESULTS: For the 114 patients scored using PRIMARY, 19 out of 37 patients with scores of 1 and 2 (51%) were diagnosed with csPCa. Of the 77 patients with PRIMARY scores between 3 and 5, 64 (83%) had csPCa. Notably, every patient with a PRIMARY score of 5 had csPCa. PRIMARY scoring had a sensitivity of 77% and specificity of 58%, with a positive predictive value of 83%. A moderate correlation was observed between PRIMARY scores and ISUP GG (Rho = 0.54, p < 0.001). In contrast, the PIRADS score displayed a sensitivity and specificity of 86% and 25% respectively, with a positive predictive value of 68%. No substantial correlation was found between PIRADS and ISUP GG. Statistical analysis revealed a significant correlation between PRIMARY and ISUP GG (p < 0.001), but not between PIRADS and ISUP GG (p = 0.281). Comparatively, PRIMARY scoring was significantly more reliable than PIRADS scoring in identifying csPCa. CONCLUSION: [68 Ga]Ga-PSMA-11 PET/CT imaging is promising for distinguishing high-risk prostate cancer patients from those apt for active surveillance, potentially aiding in the identification of csPCa.
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Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Masculino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Retrospectivos , Seleção de Pacientes , Conduta Expectante , Neoplasias da Próstata/patologia , Radioisótopos de GálioRESUMO
A ligand, 2-phenylphthalazin-1(2H)-one (K), was synthesized by refluxing 2-formylbenzoic acid with phenyl hydrazine in presence of ethanol. FTIR, elemental analysis and single crystal XRD techniques were used to elucidate the structure. Fluorimetric turn-off response was recorded when solution of ligand (K) in DMF was treated with aqueous solution of Fe3+ and Fe2+ metal ions. No specific changes were observed on addition of other metal ions (Pb2+, Cd2+, Mn2+, Zn2+, Ba2+, Ni2+, Al3+, Ag1+, Co2+, Ca2+, Cu2+, Mg2+, Cr3+). Limit of Detection (LOD) was calculated for Fe2 and Fe3+as 2.4 µM and 2.5µM respectively, which is quite below to the recommended value 5.4 µM of the Environment Protection Agency of USA. Association constants for Fe3+ and Fe2+ metal ions were determined as 6 × 10-4 M-1 and 3.6 × 10-4 M-1 respectively. Benesi-Hildebrand plot confirmed 1:1 binding ratio between metal ions and ligand.
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For many decades the success of dental implants has been considered to be dependent predominantly on the quality and quantity of the patient's alveolar bone. Grafting procedures have been commonly used to rehabilitate severely atrophic jaws but these procedures have disadvantages such as long treatment duration, major surgery, the risk of morbidity in the donor area, and high treatment costs. Recently, the use of 4 zygomatic implants has become an important treatment option in the rehabilitation of extremely atrophic maxilla. The quad zygoma technique is a method applied in cases where conventional implants cannot be used in the anterior maxilla. However, the technique has some difficulties and requires surgical experience. An alternative to the use of quad zygomatic implants is the placement of transnasal with zygomatic implants and subperiosteal implants. The aim of this case report was to present the treatment of a patient with severely atrophic maxilla with zygomatic, pterygoid, and transnasal implants.
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BACKGROUND: Medical image auto-segmentation is poised to revolutionize radiotherapy workflows. The quality of auto-segmentation training data, primarily derived from clinician observers, is of utmost importance. However, the factors influencing the quality of these clinician-derived segmentations have yet to be fully understood or quantified. Therefore, the purpose of this study was to determine the role of common observer demographic variables on quantitative segmentation performance. METHODS: Organ at risk (OAR) and tumor volume segmentations provided by radiation oncologist observers from the Contouring Collaborative for Consensus in Radiation Oncology public dataset were utilized for this study. Segmentations were derived from five separate disease sites comprised of one patient case each: breast, sarcoma, head and neck (H&N), gynecologic (GYN), and gastrointestinal (GI). Segmentation quality was determined on a structure-by-structure basis by comparing the observer segmentations with an expert-derived consensus gold standard primarily using the Dice Similarity Coefficient (DSC); surface DSC was investigated as a secondary metric. Metrics were stratified into binary groups based on previously established structure-specific expert-derived interobserver variability (IOV) cutoffs. Generalized linear mixed-effects models using Markov chain Monte Carlo Bayesian estimation were used to investigate the association between demographic variables and the binarized segmentation quality for each disease site separately. Variables with a highest density interval excluding zero - loosely analogous to frequentist significance - were considered to substantially impact the outcome measure. RESULTS: After filtering by practicing radiation oncologists, 574, 110, 452, 112, and 48 structure observations remained for the breast, sarcoma, H&N, GYN, and GI cases, respectively. The median percentage of observations that crossed the expert DSC IOV cutoff when stratified by structure type was 55% and 31% for OARs and tumor volumes, respectively. Bayesian regression analysis revealed tumor category had a substantial negative impact on binarized DSC for the breast (coefficient mean ± standard deviation: -0.97 ± 0.20), sarcoma (-1.04 ± 0.54), H&N (-1.00 ± 0.24), and GI (-2.95 ± 0.98) cases. There were no clear recurring relationships between segmentation quality and demographic variables across the cases, with most variables demonstrating large standard deviations and wide highest density intervals. CONCLUSION: Our study highlights substantial uncertainty surrounding conventionally presumed factors influencing segmentation quality. Future studies should investigate additional demographic variables, more patients and imaging modalities, and alternative metrics of segmentation acceptability.
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This study aimed to compare the effect of acid etching, sandblasting, or silica coating on the micro-shear bond strength of dual-cured resin cements to computer-aided design and computer-aided manufacturing (CAD/CAM) glass ceramic materials. Feldspathic, lithium disilicate, and zirconia-reinforced CAD/CAM ceramics were divided into four groups: control group (C), no surface treatment; hydrofluoric (HF) group, 5% HF acid-etched; sandblasting (SB) group, abraded with 50 µm aluminum oxide (Al2O3) particles; silica-coated (CJ) group, abraded with 30 µm silica-modified Al2O3 particles. Roughness values were obtained by using a profilometer. The cements were condensed on the surface-treated specimens and a micro-shear bond test was conducted. The ceramic material (p < 0.001) and surface treatment type (p < 0.001) significantly affected the micro-shear bond strength values. HF acid etching can be recommended for the surface pretreatment of feldspathic, lithium disilicate, and zirconia-reinforced CAD/CAM ceramics. Better bond strengths can be obtained with HF acid etching than with sandblasting and silica coating.
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Clinician generated segmentation of tumor and healthy tissue regions of interest (ROIs) on medical images is crucial for radiotherapy. However, interobserver segmentation variability has long been considered a significant detriment to the implementation of high-quality and consistent radiotherapy dose delivery. This has prompted the increasing development of automated segmentation approaches. However, extant segmentation datasets typically only provide segmentations generated by a limited number of annotators with varying, and often unspecified, levels of expertise. In this data descriptor, numerous clinician annotators manually generated segmentations for ROIs on computed tomography images across a variety of cancer sites (breast, sarcoma, head and neck, gynecologic, gastrointestinal; one patient per cancer site) for the Contouring Collaborative for Consensus in Radiation Oncology challenge. In total, over 200 annotators (experts and non-experts) contributed using a standardized annotation platform (ProKnow). Subsequently, we converted Digital Imaging and Communications in Medicine data into Neuroimaging Informatics Technology Initiative format with standardized nomenclature for ease of use. In addition, we generated consensus segmentations for experts and non-experts using the Simultaneous Truth and Performance Level Estimation method. These standardized, structured, and easily accessible data are a valuable resource for systematically studying variability in segmentation applications.
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Crowdsourcing , Neoplasias , Radioterapia (Especialidade) , Humanos , Feminino , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Tomografia Computadorizada por Raios X , Planejamento da Radioterapia Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/métodosRESUMO
A series of nitrile-modified N-heterocyclic carbene (NHC) complexes of Ir(III) (2a-e) and Ru(II) (3a-d) have been prepared by transmetallation of [IrCp*Cl2]2 and [RuCl2(p-cymene)]2 forming an in situ NHC-Ag complex. The structures of all complexes were characterized by 1H NMR, 13C NMR, and Fourier transform infrared (FT-IR) spectroscopies. And the structures were clearly elucidated by performing X-ray diffraction studies on 2b, 3a, and 3c single crystals. The complexes of NHC-Ir(III) (2a-e) and NHC-Ru(II) (3a-d) were investigated in the N-alkylation reaction of aniline derivatives with benzyl alcohols to form N-benzyl amines and in the N-methylation reaction of aniline derivatives with methanol. Both reactions were performed in solvent-free media. The Ir(III) complexes (2a-e) were found to perform essentially better than similar Ru(II) complexes (3a-d) in the N-alkylation and N-methylation reactions. Among the Ir(III) complexes (2a-e), the best results were obtained with 2b. The catalytic mechanisms of both reactions were revealed by 1H NMR study. Formation of Ir-hydride species was observed for both reactions. This new report provides useful information to evaluate the activity of complexes and the differences in sensitivity between the NHCs.
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We have developed a catalytic aza-Nazarov reaction of N-acyliminium salts generated in situ from the reaction of a variety of cyclic and acyclic imines with α,ß-unsaturated acyl chlorides to afford substituted α-methylene-γ-lactam heterocycles. The reactions proceed effectively in the presence of catalytic (20 mol %) amounts of AgOTf as an anion exchange agent or hydrogen-bond donors such as squaramides and thioureas as anion-binding organocatalysts. The aza-Nazarov cyclization of 3,4-dihydroisoquinolines with α,ß-unsaturated acyl chlorides gives tricyclic lactam products 7 in up to 79% yield with full diastereocontrol (dr = >99:1). The use of acyclic imines in a similar catalytic aza-Nazarov reaction with 20 mol % of AgOTf results in the formation of α-methylene-γ-lactam heterocycles 19 in up to 76% yield and with good to high diastereoselectivities (4.3:1 to 16:1). We have demonstrated the scalability of the reaction with a gram-scale example. The relative stereochemistry of the α-methylene-γ-lactam products 19 has been determined via the single-crystal X-ray analysis of lactam 19l. In order to shed light on the details of the reaction mechanism, we have performed carefully designed mechanistic studies which consist of experiments on the effect of ß-silicon stabilization, the alkene geometry of the α,ß-unsaturated acyl chloride reactants, and adventitious water on the success of the catalytic aza-Nazarov reaction.
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In the crystal structure of the title compound, C22H26BN, the B atom acts to reduce the delocalization of the nitro-gen lone-pair electron density into the pyrrole ring, so that the two N-C bonds increase in length to 1.4005â (14) and 1.3981â (14)â Å. The N-B bond length is 1.4425â (15)â Å, which is longer than a typical N-B bond because the nitro-gen lone pair is not fully available to participate in the bond.