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211.
N. Uday KumarB. Sudhakar Reddy V. Prabhakar ReddyRakeshwar Bandichhor 《Tetrahedron letters》2012,53(33):4354-4356
An efficient and convenient procedure for the reductive amination of aldehydes using NaBH4 in the presence of catalytic amount of Fe(OTf)3 is described. 相似文献
212.
Swetha Kanuganti Prabhakar R. Veerareddy Suresh Bandari 《Journal of Dispersion Science and Technology》2013,34(4):506-515
The present research is aimed to improve the oral delivery of paliperidone by loading into self-emulsifying drug delivery systems (SEDDS). Oleic acid, Tween 80, and capmul MCM L8 were selected as oil, surfactant, and co-surfactant, respectively and phase diagram was constructed and the region was identified for the formation of SEDDS. The stable formulations were analyzed for globule size, robustness to dilution and in vitro drug release. The globule size of all the formulations was found to be in the range of 205 to 310 nm with good size uniformity and seems to be dependent on the proportion of oil in SEEDS formulation. The optimized formulation (F3) has been adsorbed onto neusilin and characterized. The DSC and XRD spectra unravel the presence of molecular state of paliperidone in solid SEDDS. The in vitro dissolution study indicates improved dissolution characteristics with higher dissolution efficiency for solid SEDDS (SEDDS-N) compared to pure drug. Further ex vivo permeation studies carried out using rat intestine suggest a 2- to 3-fold improvement in permeation for SEDDS compared to pure drug. In conclusion, SEDDS prove to be potential carriers for improved oral delivery of paliperidone. 相似文献
213.
Trifluoroaceto or p-nitrobenzo-N-substituted hydroxamic acids are smoothly methylated with diazomethane and the products cleanly cleaved by hydrazine to provide the title compounds. 相似文献
214.
A simple, E-stereoselective route for the synthesis of the biologically active compounds trans-pterostilbene and tetramethoxy stilbene from the readily available starting materials 3,5-dimethoxy benzyl alcohol and 4-hydroxy benzaldehyde was developed using Julia olefination as a key reaction. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resources: Full experimental and spectral details.] 相似文献
215.
216.
Abstract Laser-induced fluorescence excitation spectra of the methoxy radical have been obtained under sufficiently high resolution in a supersonic jet expansion. The rotational structure associated with its origin band has been identified in the midst of strong overlapping rotational transitions due to the hydroxyl radical in the 31490–31700 cm?1 spectral region. Rotationally-resolved A 2A1 - X 2E spectra of the 00 0 band of methoxy have been explicitly assigned using the nomenclature for prolate symmetric top transitions in doublet states. 相似文献
217.
The main focus of this paper is to examine the consequence of laser pulses of narrow width impinging on phosphatidylcholine liposomes containing sulforhodamine dye molecules. The release of dye molecules following short-pulsed laser excitation and localized heating was measured and its dependence on laser excitation parameters studied. A characterization of the optimal conditions necessary for release of liposome contents can be applied to the targeted delivery of therapeutic drugs. 相似文献
218.
219.
Cis 3 and trans methyl 7-oxo-podocarpa-8, 11, 13-trien-15-oate 4 are synthesized in high yields by photo-oxygenation of cis 1 and trans methyl podocarpa-8, 11, 13-trien-15-oate 2 obtained from dehydroabietic acid. 相似文献
220.
Emmadi Narender Reddy Atmakur Krishnaiah Tadikamalla Prabhakar Rao 《Tetrahedron: Asymmetry》2013,24(12):724-728
The stereoselective total synthesis of Ieodomycin A and B, bioactive secondary metabolites from marine sources with potent anti-microbial activity was achieved starting from commercially available geranial. The key steps involved in the synthetic sequence of Ieodomycin A and B are the Sharpless asymmetric epoxidation, the formation of a β-ketoester, and the 1,3-anti reduction. The synthesis of C-3 epimer of Ieodomycin A and B was also accomplished in good yields. 相似文献