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Complexes of secondary amines with borane, R2NH·BH3, surpass sodium borohydride as reducing agents for saturated and unsaturated steroidal 3-, 12-, 17-, and 20-ketones as regards chemo- and regioselectivity and mildness of the reaction conditions. In the case of 12-ketones, stereoselectivity is also improved. 相似文献
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A new, edited HMBC experiment is introduced that leads to two subspectra according to the number of protons attached to 13C nuclei being even or odd, i.e. one subspectrum with C + CH2 and another with CH + CH3. This experiment can be useful for resolving spectral overlap among the typically large number of peaks in HMBC spectra. It is implemented in a broadband version similar to broadband HMBC and demonstrated on prednisolone [(11beta)-11,17,21-trihydroxypregna-1,4-diene-3,20-dione]. 相似文献
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《Analytical letters》2012,45(3):619-630
Abstract In the present work, a photochemical derivatization procedure to induce fluorescence from two synthetic glucocorticoids (triamcinolone acetonide and prednisolone) was developed. The procedure consisted of the exposure of analyte acidic solutions to ultraviolet (UV) radiation (254 and 300 nm) in a photochemical reactor at 65°C. Experimental parameters such as type and concentration of the acid, composition of the solvent system, and sample treatment time in the reactor were found to be critical, and, therefore, they were carefully optimized. The intensity of the fluorescence (240/350 nm) and the stability of the signal were, appropriated for analytical purposes. Limits of detection (LD) of 5 and 6 µg L?1, respectively, for triamcinolone acetonide and prednisolone were achieved. Linear dynamic range for both analytes extended up to 20 mg L?1. The spectrofluorimetric determination of prednisolone and triamcinolone acetonide was tested by the analysis of different anti‐inflammatory pharmaceutical formulations (tablets, ointment, and veterinary parenteral suspensions). The recoveries achieved were between 95% and 107%. A study to evaluate the effect of potential interferents (polimixine B and benzocaine) on the fluorescence signal of the analytes also has been done. 相似文献
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New versions of the H2BC pulse sequence (Nyberg NT, Duus JØ, Sørensen OW. J. Am. Chem. Soc. 2005; 127: 6154) that edit into two subspectra according to the number of protons attached to 13C nuclei being odd or even are introduced. These sequences can be useful for resolving spectral overlap, which is demonstrated on the molecule prednisolone [(11 β)‐11,17,21‐trihydroxypregna‐1,4‐diene‐3,20‐dione] Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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《Acta Crystallographica. Section C, Structural Chemistry》2017,73(6):430-436
Prednisolone acetate {systematic name: 2‐[(8S ,9S ,10R ,13S ,14S ,17R )‐11,17‐dihydroxy‐10,13‐dimethyl‐3‐oxo‐6,7,8,9,10,11,12,13,14,15,16,17‐dodecahydro‐3H‐cyclopenta[a ]phenanthren‐17‐yl]‐2‐oxoethyl acetate}, is an ophthalmic drug that belongs to the class of corticosteroids. Its crystal structure was refined using the classical independent atom model (IAM) and a transferred multipolar atom model using the ELMAM2 database. The results of both refinements have been compared. The ELMAM2 refinement was found to be superior in terms of the refinement statistics. It has been shown that certain electron‐density‐derived properties can be calculated on the basis of the transferred parameters for crystals which diffract to ordinary resolution. The procedure proves helpful in understanding the mode of action of the drug molecule. 相似文献
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Xavier Matabosch Oscar J. Pozo Clara Pérez‐Mañá Esther Papaseit Jordi Segura Rosa Ventura 《Journal of mass spectrometry : JMS》2015,50(3):633-642
Glucocorticosteroids are prohibited in sports when used by systemic administrations (e.g. oral), whereas they are allowed using other administration ways. Strategies to discriminate between administrations routes have to be developed by doping control laboratories. For this reason, the metabolism of prednisolone (PRED) was studied using liquid chromatography coupled to tandem mass spectrometry. A single oral (10 mg) dose of PRED was administered to two healthy male volunteers. Urine samples were collected up to 6 days after administration. Samples were hydrolyzed with β‐glucuronidase and subjected to liquid–liquid extraction with ethyl acetate in alkaline conditions. The extracts were analyzed by liquid chromatography coupled to tandem mass spectrometry. Precursor ion scan methods (m/z 77, 91, 105, 121, 147 and 171) in positive ionization and neutral loss scan methods (76 and 94 Da) in negative ionization modes were applied for the open detection of PRED metabolites. Using these methods, PRED parent compound plus 20 metabolites were detected. PRED and 11 metabolites were characterized by comparison with standards of the compounds (PRED, prednisone, 20β‐dihydro‐PRED and 20α‐dihydro‐PRED, 20β‐dihydro‐prednisone and 20α‐dihydro‐prednisone, 6β‐hydroxy‐PRED and 6α‐hydroxy‐PRED, 20β isomers and 20α isomers of 6β,11β,17α,20,21‐pentahydroxypregnan‐1,4‐diene‐3‐one, 6α,11β,17α,20β,21‐pentahydroxypregnan‐1,4‐diene‐3‐one and Δ6‐PRED). Using mass spectrometric data, feasible structures were proposed for seven of the remaining nine detected metabolites, including several 6‐hydroxy‐metabolites. Eleven of the characterized metabolites have not been previously described. Maximum excretion rates for PRED metabolites were achieved in first 24 h; however, most of the metabolites were still detectable in the last collected samples (day 6). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Nessreen S. Abdelhamid Maimana A. Magdy Basma H. Anwar Nehal F. Farid 《Biomedical chromatography : BMC》2022,36(5):e5343
Recently, prednisolone has been used in treating many medical conditions, such as autoimmune diseases and cancer. It is also prescribed to mitigate the respiratory complications caused by COVID-19 infection. It can cause some health complications, such as GIT ulcers, so it should be co-administered with proton-pump inhibitors, such as esomeprazole, to prevent the risk of ulcers. This work aims to develop an ecofriendly and sensitive TLC method for simultaneous determination of esomeprazole and prednisolone in their binary mixtures and spiked human plasma. Separation was performed using a mixture of ethyl acetate, methanol, and ammonia (9.5:0.5:0.1, v/v/v) as an eluting system with UV scanning at 245 nm. Dapoxetine was used as an internal standard to correct the variation during sampling. The resulting Rf values for plasma, esomeprazole, prednisolone, and dapoxetine were 0.03, 0.51, 0.72 and 0.85, respectively. Four greenness assessment tools—national environmental method index, eco-scale assessments, analytical greenness metric approach (AGREE), and green analytical procedure index (GAPI)—were used to evaluate the greenness characteristics of the proposed method to the environment, and the results were acceptable and satisfactory. Validation parameters were checked according to the US FDA guidelines to achieve the international requirements for bioanalytical method validation, and the results were within the accepted ranges. 相似文献