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1.
Pediatr Surg Int ; 40(1): 2, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37991549

RESUMEN

PURPOSE: To identify risk factors for delayed oral nutrition in infants with a congenital diaphragmatic hernia (CDH) and its impact on developmental delay at 18 months of age. METHODS: This retrospective single-center cohort study compared the clinical parameters in patients with isolated CDH born and treated at our hospital between 2006 and 2020. We evaluated clinical features significantly related to delayed oral nutrition (defined as taking ≥ 30 days from weaning from mechanical ventilation to weaning from tube feeding). RESULTS: Twenty-six of the 80 cases had delayed oral nutrition. Univariate analyses showed significant differences. Multivariate analyses were performed on the three items of preterm delivery, defect size (over 50% to nearly entire defect), and ventilation for ≥ 9 days. We identified the latter two items as independent risk factors. The adjusted odds ratios were 4.65 (95% confidence interval, 1.27-7.03) and 6.02 (1.65-21.90), respectively. Delayed oral nutrition was related to a significantly higher probability of developmental delay at 18 months (crude odds ratio 4.16, 1.19-14.5). CONCLUSION: In patients with CDH, a large defect and ventilatory management over 9 days are independent risk factors for delayed oral nutrition, which is a potent predictor of developmental delay that requires active developmental care.


Asunto(s)
Hernias Diafragmáticas Congénitas , Recién Nacido , Humanos , Lactante , Hernias Diafragmáticas Congénitas/complicaciones , Hernias Diafragmáticas Congénitas/terapia , Estudios de Cohortes , Estudios Retrospectivos , Factores de Riesgo , Respiración Artificial
2.
Pediatr Surg Int ; 39(1): 273, 2023 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-37718339

RESUMEN

PURPOSE: This study aimed to investigate the incidence and clinical factors associated with undescended testes (UDT) in patients with congenital diaphragmatic hernia (CDH). METHODS: We retrospectively reviewed the incidence of UDT in male neonates admitted to our institution and underwent surgery for CDH between January 2006 and December 2022. Patients were divided into two groups based on the presence or absence of UDT, and risk factors for UDT were compared between the two groups. RESULTS: Among the 66 male neonates with CDH, 16 (24.2%) developed UDT. Patients with UDT had a significantly smaller gestational age (p = 0.026), lower birth weight (p = 0.042), and lower Apgar score at 1 min (p = 0.016) than those without UDT. They had a significantly higher incidence of large diaphragmatic defects (p = 0.005), received more patch closures (p = 0.020), had a longer mechanical ventilation period (p = 0.034), and longer hospital stay (p = 0.028). Multiple logistic regression analysis revealed that large diaphragmatic defect was an independent risk factor for UDT (adjusted odds ratio of 3.87). CONCLUSION: CDH and UDT are strongly correlated. In patients with CDH, the incidence of UDT was related not only to patients' prematurity but also to the large diaphragmatic defect. Large diaphragmatic defect is an independent risk factor for UDT in patients with CDH.


Asunto(s)
Criptorquidismo , Hernias Diafragmáticas Congénitas , Recién Nacido , Humanos , Masculino , Criptorquidismo/complicaciones , Criptorquidismo/epidemiología , Criptorquidismo/cirugía , Hernias Diafragmáticas Congénitas/epidemiología , Hernias Diafragmáticas Congénitas/cirugía , Estudios Retrospectivos , Factores de Riesgo , Peso al Nacer
3.
Angew Chem Int Ed Engl ; 62(47): e202310976, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37650440

RESUMEN

For the application of CO2 as an energy storage material, a H2 storage system has been proposed based on the interconversion of CO2 and formic acid (or formate). However, energy losses are inevitable in the conversion of electrical energy to H2 as chemical energy (≈70 % electrical efficiency) and H2 to electrical energy (≈40 % electrical efficiency). To overcome these significant energy losses, we developed a system based on the interconversion of CO2 and formate for the direct storage and generation of electricity. In this paper, we report an aqueous redox flow battery system using homogeneous Ir catalysts with CO2 -formate redox pair. The system exhibited a maximum discharge capacity of 10.5 mAh (1.5 Ah L-1 ), capacity decay of 0.2 % per cycle, and total turnover number of 2550 after 50 cycles. During charging-discharging, in situ fluorescence X-ray absorption fine structure spectroscopy based on an online setup indicated that the active species was in a high valence state of IrIV .

4.
Pediatr Surg Int ; 39(1): 91, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36695959

RESUMEN

PURPOSE: This study aimed to evaluate the feasibility and safety of laparoscopic resection of abdominal neuroblastoma by comparing operative and long-term oncologic outcomes between open and laparoscopic surgeries. METHODS: This single-center retrospective study included patients who underwent laparoscopic tumor resection, between January 2000 and June 2021, with a maximum tumor diameter of ≤ 60 mm and without image-defined risk factors (IDRFs) at surgery. Data from 35 abdominal neuroblastoma resections were reviewed and compared between the laparotomy and laparoscopic groups. RESULTS: Nineteen patients underwent laparotomy and 16 had laparoscopic tumor resection. All laparoscopic surgeries achieved complete resection without conversion to open surgery. Median blood loss was significantly lower in the laparoscopic group (0.6 mL/kg) than in the laparotomy group (8.4 mL/kg) (P < 0.0001). There were two locoregional recurrences in the laparoscopic group and two metastatic recurrences in the laparotomy group. Five-year overall survival was 93.8% in both groups. CONCLUSION: Laparoscopic resection of abdominal neuroblastomas in children is a feasible and safe procedure for tumors ≤ 60 mm in diameter with no IDRFs at surgery, with long-term outcomes equivalent to laparotomy.


Asunto(s)
Laparoscopía , Neuroblastoma , Humanos , Niño , Resultado del Tratamiento , Estudios Retrospectivos , Estudios de Factibilidad , Recurrencia Local de Neoplasia/cirugía , Laparoscopía/métodos , Neuroblastoma/cirugía
5.
J Vet Med Sci ; 85(1): 88-91, 2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36436844

RESUMEN

We examined the clinical signs and necropsy findings of a mountain hawk-eagle (Nisaetus nipalensis) that died during rehabilitation. The bird was rescued and treated for open fracture of the right forearm. During rehabilitation, the bird could not stand up or fly. Part of the right secondary and left and right primary feathers were removed during rehabilitation; additional fracture was found in the right tibiotarsus and treated. However, the bird died 92 days after rescue and necropsy was performed. Severe hepatic lipidosis and capture myopathy were confirmed by histopathological examinations. These lesions may be associated with the cause of death of this animal. Accumulation of information is expected to contribute to the improvement of effective rehabilitation techniques for raptors.


Asunto(s)
Enfermedades de las Aves , Águilas , Halcones , Rapaces , Animales , Enfermedades de las Aves/diagnóstico
6.
Chem Asian J ; 18(1): e202201047, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36398386

RESUMEN

We performed X-ray absorption studies for the electrolytes of a Ti-Mn redox flow battery (RFB) to understand the redox reaction of the Ti/Mn ions and formation of precipitates in charged catholyte, because suppression of the disproportionation reaction is a key to improve the cyclability of Ti-Mn RFB and enhance the energy density. Hard X-ray absorption spectroscopy with a high transmittance and soft X-ray absorption spectroscopy to directly observe the 3d orbitals were complementarily employed. Moreover, the Ti/Mn 3d electronic structure for each precipitate and solution in the charged catholyte was investigated by using scanning transmission X-ray microscopy: the valence of Mn in the precipitate is mostly attributed to 4+, and the solution includes only Mn2+ . This charge disproportionation reaction should occur after the Mn ions in the catholyte should be oxidized from Mn2+ to Mn3+ by charge.


Asunto(s)
Electrólitos , Titanio , Espectroscopía de Absorción de Rayos X , Oxidación-Reducción
7.
Pediatr Surg Int ; 38(11): 1577-1583, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36053329

RESUMEN

PURPOSE: Fetuses with persistent cloaca are known to develop urine or meconium backflow into the abdominal cavity caused by obstruction of the common channel, thus leading to fetal peritonitis with fetal ascites. We analyzed the impact of prenatal fetal ascites on postnatal clinical features and management. METHODS: This retrospective single-center cohort study was conducted to compare the perinatal parameters of patients with isolated persistent cloaca who were born and treated at our hospital between 1991 and 2021. The clinical features and management of those with and without fetal ascites were compared. RESULTS: Among the 17 eligible patients, fetal ascites were recognized in seven. The occurrence of fetal ascites was significantly related to preterm birth, higher birth weight z-score, birth via emergency cesarean delivery, low Apgar scores at 1 min and 5 min, higher C-reactive protein levels at birth, longer duration of oxygen administration, the need for a urinary drainage catheter at initial discharge, and shorter neonatal hospital stays. CONCLUSIONS: The postnatal management of patients with persistent cloaca with fetal ascites differed significantly from that of patients without fetal ascites. For patients with unexplained fetal ascites, magnetic resonance imaging may be helpful for determining the definite diagnosis of persistent cloaca.


Asunto(s)
Anomalías del Sistema Digestivo , Enfermedades Intestinales , Nacimiento Prematuro , Animales , Ascitis/diagnóstico por imagen , Ascitis/etiología , Ascitis/terapia , Proteína C-Reactiva , Cloaca , Estudios de Cohortes , Anomalías del Sistema Digestivo/complicaciones , Femenino , Humanos , Recién Nacido , Oxígeno , Embarazo , Estudios Retrospectivos , Ultrasonografía Prenatal
8.
Pediatr Surg Int ; 38(2): 317-323, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34981147

RESUMEN

PURPOSE: To assess the risk factors for surgical site infections (SSIs) post-abdominal surgery in neonates. METHODS: A retrospective, single-center cohort study was conducted using patient data from 2009 to 2018. Patient characteristics and several variables were analyzed to identify independent risk factors for SSI. RESULTS: SSI occurred in 39/406 procedures (9.6%). Univariate analysis showed that the incidence of SSI was significantly higher in patients who had undergone multiple surgical procedures (P = 0.032), prolonged operations (P = 0.016), long-term hospitalization (P < 0.001), long-term antibiotic administration (P < 0.001), with methicillin-resistant Staphylococcus aureus (MRSA) colonization (P = 0.044), contaminated/dirty wounds (P < 0.001), and American Society of Anesthesiologists physical status of 3 or 4 (P = 0.021). Multivariate analysis identified prolonged operations [odds ratio (OR): 2.91 (1.21-8.01)] and contaminated/dirty wounds [OR: 5.42 (2.41-12.1)] as independent risk factors. Patients with SSI had a higher incidence of MRSA colonization (27.8% vs. 14.8%, P = 0.044), longer antibiotic administration (24 days vs. 8 days, P = 0.049), and longer hospitalization times (98 days vs. 43 days, P = 0.007) than those without SSIs. CONCLUSIONS: Long operations exceeding 100 min and surgical procedures with contaminated/dirty wounds are independent risk factors for neonatal SSIs after abdominal surgery. SSIs were related to MRSA colonization during hospitalization, long-term antibiotic administration, and long-term hospitalization.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Estudios de Cohortes , Humanos , Incidencia , Recién Nacido , Estudios Retrospectivos , Factores de Riesgo , Infecciones Estafilocócicas/epidemiología , Infección de la Herida Quirúrgica/epidemiología
9.
Org Lett ; 23(2): 480-485, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33375788

RESUMEN

A diaminomethylenemalononitrile organocatalyst efficiently promotes the asymmetric direct vinylogous conjugate additions of α-angelica lactones to benzoyl acrylonitrile derivatives, resulting in the corresponding addition products bearing vicinal tertiary and quaternary stereogenic centers with excellent enantioselectivities (up to 99% ee). This report is the first successful example of the asymmetric conjugate additions of α-angelica lactone to benzoyl acrylonitriles. The chiral γ,γ-disubstituted γ-butenolides obtained can be readily transformed to the bicyclic γ-lactam derivative as a valuable synthetic intermediate.

10.
J Control Release ; 329: 1037-1045, 2021 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-33080271

RESUMEN

Safe and efficient gene therapy for the treatment of Duchenne muscular dystrophy (DMD), a genetic disorder, is required. For this, the muscle-targeting delivery system of genes and nucleic acids is ideal. In this study, we focused on the A2G80 peptide, which has an affinity for α-dystroglycan expressed on muscle cell membranes, as a muscle targeted nanocarrier for DMD and developed A2G80-modified liposomes. We also prepared A2G80-modified liposomes coated with long- and short-chain PEG, called A2G80-LSP-Lip, to improve the blood circulation of liposomes using microfluidics. The liposomes had a particle size of approximately 80 nm. A2G80-LSP-Lip showed an affinity for the muscle tissue section of mice by overlay assay. When the liposomes were administered to DMD model mice (mdx mice) via the tail vein, A2G80-LSP-Lip accumulated efficiently in muscle tissue compared to control liposomes. These results suggest that A2G80-LSP-Lip can function as a muscle-targeting liposome for DMD via systemic administration, and may be a useful tool for DMD treatment.


Asunto(s)
Distrofia Muscular de Duchenne , Animales , Modelos Animales de Enfermedad , Distroglicanos , Liposomas , Ratones , Ratones Endogámicos mdx , Músculo Esquelético , Músculos , Distrofia Muscular de Duchenne/tratamiento farmacológico , Péptidos
11.
Surg Case Rep ; 6(1): 170, 2020 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-32654033

RESUMEN

BACKGROUND: Diaphragmatic hernia is a rare complication of ventricular assist device (VAD), mainly developing after explantation of the device. We herein report a case of diaphragmatic hernia that developed following the implantation of VAD. CASE PRESENTATION: A 4-month-old girl with a diagnosis of dilated cardiomyopathy underwent VAD implantation for a bridge to heart transplantation. Three months later, intermittent vomiting developed, and left-sided diaphragmatic hernia was confirmed on plain X-ray and computed tomography. Without any findings of ischemia, we performed elective thoracoscopic repair of the diaphragmatic hernia. In the right decubitus position, thoracoscopy revealed the small intestine to be herniated into the left thorax. After reduction of the herniated intestine, the defect of the diaphragm (3 × 2 cm in size) was directly closed with interrupted non-absorbable sutures. Her postoperative course was uneventful. CONCLUSION: Thoracoscopic repair of diaphragmatic hernia associated with VAD implantation may be a safe approach.

12.
Gan To Kagaku Ryoho ; 47(3): 487-489, 2020 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-32381924

RESUMEN

BACKGROUND: Since the introduction of the guideline for the diagnosis and treatment of esophageal carcinoma in 2007, the indication for placing an esophageal stent has changed, especially with respect to the treatment of esophageal stricture after chemoradiotherapy(CRT). For CRT cases, irradiation after stent placement and stent placement after CRT are not recommended due to the risk of perforation. METHODS: Thirty-eight patients who underwent esophageal stenting in our department between January 2007 and December 2018 and who were diagnosed with thoracic esophageal cancer were included in this study. We retrospectively examined the safety and treatment effect of esophageal stent placement. RESULTS: Prior cancer therapy was observed in 16 cases(8 cases of chemotherapy and 8 cases of CRT). In the no prior therapy group, 13 cases were treated with BSC and 9 cases with chemotherapy. Esophageal stent placement after CRT was performed in 8 cases. Esophageal stent was placed 9(6-14)months after CRT. The stent patency period was 5(1-11)months, and the survival period after stent placement was 6(1-12)months. There was no difference in the frequency of complications and treatment outcomes of the CRT group compared with the non-CRT group. CONCLUSION: Cases undergoing esophageal stent placement after CRT can expect therapeutic effects similar to those of other cases. However, complications such as perforation can be fatal; thus, careful consideration should be given to each individual case for esophageal stent placement after CRT.


Asunto(s)
Neoplasias Esofágicas , Estenosis Esofágica , Stents , Neoplasias Esofágicas/complicaciones , Estenosis Esofágica/etiología , Estenosis Esofágica/cirugía , Humanos , Estudios Retrospectivos
13.
Org Lett ; 21(8): 2606-2609, 2019 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-30924673

RESUMEN

An organocatalyzed method for synthesizing chiral γ,γ-disubstituted γ-butenolides via direct vinylogous aldol reactions of γ-substituted ß,γ-butenolides with aldehydes is reported. This reaction is catalyzed by a squaramide-sulfonamide organocatalyst to afford a range of anti-aldol adducts possessing vicinal quaternary and tertiary stereocenters with high to excellent enantioselectivities (reaching 95% ee). This is the first report of a successful stereoselective direct vinylogous aldol reaction of aldehydes with γ-substituted ß,γ-butenolides.

14.
Circ Rep ; 1(7): 286-295, 2019 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-33693152

RESUMEN

Background: Pathogenesis of heart failure with preserved ejection fraction (HFpEF) may involve endothelial dysfunction and abnormal vascular structure. Sodium-glucose cotransporter 2 (SGLT2) inhibitors have beneficial cardiovascular effects and may improve vascular function in patients with HFpEF. Methods and Results: We recruited 184 patients with type 2 diabetes and HFpEF (mean age, 66.0±14.4 years) who were scheduled for treatment with SGLT2 inhibitors, had transthoracic echocardiogram to identify diastolic function, and flow-mediated dilation (FMD) to evaluate endothelial function, and assessed cardio-ankle vascular index (CAVI) and carotid intima-media thickness as indices of vascular function and vascular structure, respectively. Body weight, systolic blood pressure, diastolic blood pressure, triglycerides, remnant lipoprotein cholesterol, fasting plasma glucose, hemoglobin A1c, urinary albumin/creatinine ratio, and insulin resistance (IR) decreased, hematocrit and FMD increased significantly, and CAVI decreased significantly, after 12-week treatment (P<0.05). Short-term SGLT2 inhibitors improved diastolic function, significantly reducing the mitral ratios of septal E/early septal annular tissue Doppler velocity (P=0.003) and lateral E/early lateral e' (P=0.044). On multiple regression statistically significant associations were seen between ∆mean E/e' and ∆FMD, ∆CAVI, and ∆IR. Conclusions: SGLT2 inhibitors can improve diastolic function in patients with type 2 diabetes, suggesting that current treatment policies for diabetes should be re-examined. Further prospective studies with larger sample sizes could provide mechanistic insights into the benefits of SGLT2 inhibitors.

15.
Int J Surg Case Rep ; 54: 83-86, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30553095

RESUMEN

INTRODUCTION: Enteric duplication cysts are rare and, in addition, isolated enteric duplication cysts are lower morbidity prevalence rate. These cysts lack a connection to the gastrointestinal tract or the adjacent mesenteric vasculature and have only been reported in 10 case reports. In these reports, only two reports were cases with malignant transformation. Our case was a report for the advanced cancer of the isolated enteric duplication cyst. CASE PRESENTATION: The patient was a 43 year-old woman with slightly abdominal pain and mass formation. The abdominal contrast-enhanced computed tomography showed 130 × 100 × 90 mm huge cystic mass existed in right upper peritoneal cavity. The cystic mass had thickened wall and many enhanced nodules. As these imaging findings suggested a tumor originated from pancreas and the preoperative diagnose was suspect of mucinous cystic neoplasm. In operative findings, the tumor originated from pancreatic head and did not attach to gastrointestinal tract. Final pathology indicated the cyst was an isolated advanced enteric duplication cyst cancer and not originated from pancreas. CONCLUSION: We experienced an extremely rare case of completely isolated advanced enteric duplication cyst cancer. Unique to this case, the preoperative diagnosis was suspect of mucinous cystic neoplasm arising from pancreas head and partial pancreatectomy was performed. However, in the pathological findings, this cyst diagnosed advanced enteric duplication cyst cancer.

16.
Angew Chem Int Ed Engl ; 57(29): 9073-9077, 2018 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-29766627

RESUMEN

The hydrogen evolution reaction using semiconductor photocatalysts has been significantly improved by cocatalyst loading. However, there are still many speculations regarding the actual role of the cocatalyst. Now a photocatalytic hydrogen evolution reaction pathway is reported on a cocatalyst site using TiO2 nanosheets doped with Rh at Ti sites as one-atom cocatalysts. A hydride species adsorbed on the one-atom Rh dopant cocatalyst site was confirmed experimentally as the intermediate state for hydrogen evolution, which was consistent with the results of density functional theory (DFT) calculations. In this system, the role of the cocatalyst in photocatalytic hydrogen evolution is related to the withdrawal of photo-excited electrons and stabilization of the hydride intermediate species; the presence of oxygen vacancies induced by Rh facilitate the withdrawal of electrons and stabilization of the hydride.

17.
Gan To Kagaku Ryoho ; 45(13): 1889-1891, 2018 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-30692388

RESUMEN

A 73-year-old man was admitted to our hospital with anal pain. The 10 cm tumor was observed externally at the 3 o' clock side of his anus. He was unable to maintain the sitting position because of pain and had fecal incontinence and erosive skin inflammation. We identified this anal stenosis as anal canal adenocarcinoma(moderately differentiated). Thereby, no distant metastasis was found; we decided to treat the patient with conventional therapy. We made a double-hole colostomy in the sigmoid colon, and then the patient received preoperative chemoradiotherapy(CRT). Radiation therapy(RT)was adminis- tered at 40 Gy/20 Fr and oral capecitabine of 825mg/m / 2/time was administered twice a day on the RT days. The tumor shrinkage was good, and then we performed a laparoscopy-assisted abdominoperineal resection of the rectum. Pathologically therapeutic effect was Grade 1b. His activity of daily living was dramatically improved, and he can now main tan the sitting position. Twelve months postoperatively, he has no sign of recurrence. In this case, we experienced an anal canal adenocarcinoma that was possibly locally controlled by preoperative CRT and rectal amputation.


Asunto(s)
Adenocarcinoma , Neoplasias del Ano , Neoplasias del Recto , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirugía , Anciano , Amputación Quirúrgica , Canal Anal , Neoplasias del Ano/diagnóstico , Neoplasias del Ano/cirugía , Quimioradioterapia , Humanos , Masculino , Recurrencia Local de Neoplasia , Neoplasias del Recto/diagnóstico , Neoplasias del Recto/cirugía
18.
Gan To Kagaku Ryoho ; 45(13): 1898-1900, 2018 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-30692391

RESUMEN

A 94-year-old woman, who had been treated for multiple colon cancers 4 years ago, complained of umbilicus induration and had been followed up in a previous hospital with a diagnosis of periumbilical inflammation. Four years and 3 months postoperatively, the umbilical induration was enlarged, and umbilical metastasis of adenocarcinoma was diagnosed on biopsy. Umbilical resection was performed, and multiple peritoneal metastases were revealed. Umbilical metastases may worsen the patient's quality of life; thus, local resection was recommended positively.


Asunto(s)
Adenocarcinoma , Neoplasias del Colon , Nódulo de la Hermana María José , Adenocarcinoma/cirugía , Anciano de 80 o más Años , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Femenino , Humanos , Calidad de Vida , Nódulo de la Hermana María José/diagnóstico , Nódulo de la Hermana María José/etiología , Nódulo de la Hermana María José/cirugía , Ombligo
19.
J Org Chem ; 82(9): 4661-4667, 2017 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-28394134

RESUMEN

Asymmetric direct vinylogous aldol reactions of furan-2(5H)-one with aldehydes in the presence of a catalytic amount of novel squaramide-sulfonamide organocatalyst resulted in the corresponding addition products with high to excellent enantioselectivities. This is the first successful report illustrating an example of highly stereoselective reactions using a squaramide-sulfonamide organocatalyst.

20.
Chem Pharm Bull (Tokyo) ; 64(12): 1781-1784, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27904086

RESUMEN

Diaminomethylenemalononitrile organocatalysts promote the asymmetric chlorination of simple cyclic ß-keto esters such as methyl, ethyl, and benzyl esters of 1-oxo-2,3-dihydro-1H-indene-2-carboxylic acid. This affords the corresponding chiral α-chlorinated carbonyl products in excellent yields with high enantioselectivities.


Asunto(s)
Diaminas/química , Ésteres/química , Halogenación , Hidrocarburos Clorados/síntesis química , Nitrilos/química , Catálisis , Hidrocarburos Clorados/química , Estructura Molecular , Estereoisomerismo
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