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A new versatile strategy involving a sequential four-component reaction of the nitroketene dithioacetals, alkylamine/benzylamine, isatin and various enolizable active methylene structures (pyrazolone, barbituric acid, 1,3-indandione and 2-hydroxy-1,4-naphthoquinone) as precursors under mild and catalyst-free conditions results in the synthesis of new functionalized spirooxindole pyrans named spiro[indoline-3,4′-pyrano[2,3-c]pyrazol], spiro[indoline-3,5′-pyrano[2,3-d]pyrimidine], spiro[indeno[1,2-b]pyran-4,3′-indoline] and spiro[benzo[g]chromene-4,3′-indoline] in moderate to good yields. The use of various active methylene compounds affords a range of skeletally distinct spirooxindole-based heterocycles with potential biological properties. The present strategy has many advantages, such as convenient one-pot operation, simple workup procedures and straightforward isolation without using tedious purification steps such as column chromatography, progress under catalyst-free condition and high molecular diversity.

Synthesis of spirooxindole pyrans by a sequential four-component reaction of nitroketene dithioacetals, alkylamine/benzylamine, isatin, and active methylene compounds.  相似文献   
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Three new triazole meso-arylporphyrins (4a–c) were synthesized by the copper(i)-catalyzed azide alkyne cycloaddition (CuAAC) “click” reaction in high yield. The corresponding zinc(ii) coordination compounds (5a–c) have also been prepared. All 4a–c and 5a–c porphyrin species were fully characterized by elemental analysis, electrospray ionization and MALDI-TOF mass spectrometry, infrared spectroscopy, proton nuclear magnetic resonance, UV-visible, fluorescence and cyclic voltammetry. The zinc(ii) 5a–c complexes have been tested as detectors for Cl and Br anions. UV-visible titrations reveal that these host systems exhibit strong anion binding affinities. The efficiency of the adsorption of the malachite green dye (MG) dye on the 4a–c free base porphyrins and the corresponding zinc(ii) complexes 5a–c was investigated by a kinetic study using these synthetic porphyrin derivatives as adsorbents. The use of our triazole Zn(ii) complexes in the catalytic degradation of the MG dye is the first example where a metalloporphyrin is involved in the MG dye decolorization reaction. The degradation reactions were carried out using an ecological oxidant (H2O2), where the efficiency of the decolorization has been characterized by UV-visible spectroscopic analysis. Several factors affecting the degradation phenomenon have been studied. The energetic parameters concerning the degradation process have also been determined.

Three triazole porphyrins and there corresponding zinc complexes are described as well as their spectroscopic and electrochemical data. The chloride and bromide sensing efficiency and the degradation of the malachite green dye are also reported.  相似文献   
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A 14 year old boy is presented who was admitted to the psychiatric ward because of delirium. He also had gynaecomastia, facial oedema, striae, and hypertension. He was finally proved to have a mixed oestrogen and cortisol producing adrenal tumour which was removed surgically with complete improvement and no relapse.  相似文献   
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OBJECTIVE: Evaluation of the clinical characteristics of burning mouth complaints (BMC) in a series of Brazilian patients referred to a large teaching hospital. MATERIALS AND METHODS: 66 patients with burning mouth complaints were evaluated through a standardized protocol. RESULTS: 56 women and 10 men were examined, ranging in age from 35-83 years. The primary location of the complaints was reported to be the tongue. Thirty-six patients reported a precipitating event. The mean VAS pain levels were 7.5 in women and 6.11 in men. The average estradiol levels in women were low (<13 pg/ml); 80% of all patients reported a concomitant chronic disease, 55% of all patients wore total dentures, 54% of all patients reported subjective xerostomia, 48% of all patients reported sleep disturbances and 66% reported phantom taste. No statistical differences were found between groups with or without a precipitating event in VAS: (p=0.139), in the Number of Words Chosen (NWC) (p=0.259) and Pain Rating Index (PRI) (p=0.276) sections of the McGill Pain Questionnaire (MPQ). CONCLUSION: The existence of systemic comorbidities, self-reported sleep disturbances and taste alterations indicates possible correlations and the need for a careful systemic evaluation of each patient; there were no differences between patients with and without precipitating events.  相似文献   
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