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41.
Saeed Kamali Hongxin Wang Devrani Mitra Hideaki Ogata Wolfgang Lubitz Brian C. Manor Thomas B. Rauchfuss Deborah Byrne Violaine Bonnefoy Francis E. Jenney Michael W. W. Adams Yoshitaka Yoda Ercan Alp Jiyong Zhao Stephen P. Cramer 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(2):752-756
42.
Majid M. Heravi Fereshteh Hydarzadeh Yahya Farhangi Mitra Ghassemzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1473-1475
Primary and secondary trimethylsilyl ethers are effeciently converted to the corresponding carbonyl compounds using HZSM-5 zeolite-supported CrO 3 under microwave irradiation in solventless system. 相似文献
43.
Hossein A. Oskooie Azam Ranjbaran Majid M. Heravi Mitra Ghassemzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1711-1714
Reduction of aromatic nitro compounds to amine with hydroiodic acid was revisited. Under microwave irradiation on solid support the reduction proceeded efficiently and rapidly. 相似文献
44.
Majid M. Heravi Hossein A. Oskooie Pegah Kazemian Fatemeh Drikvand Mitra Ghassemzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2341-2344
Cerium ammonium nitrate (CAN) adsorbed on HNO 3 /silica gel is a mild reagent for selective oxidation of benzylic alcohols to the corresponding aldehydes under microwave irradiation in solventless system. 相似文献
45.
Aplysin (1), a marine sesquiterpene was isolated from ‘aplysia kurodai’ and its structure was ellucidated by Hirata-et-al1. They also reported the synthesis of racemic aplysin2. Their synthetic route involved cyclopentanone (2) as a well-characterized intermediate. We visualized the synthesis of cyclobutanone (3) and its subsequent conversion to (2) as an attractive alternative. But during our attempts to synthesize the said cyclobutanone, we have come across a very facile intramolecular ‘ene’ reaction between ketene and olefin. We report our unexpected observations in this communication. 相似文献
46.
Z-6-Heneicosen-11-one (1) and Z-1,6-Heneicosen-11-one (2) are the sex pheromones of the Douglas-Fir Tussock moth, ‘Orgyia Pseudo Sugata’, isolated1,2 in 1975 and 1978 respectively. In contrast with other lepidopterous pheromones, which are unsaturated C12-C14 primary alcohols or acetates, these were found to be C21 ketones. The Douglas-Fir Tussock moth is a severe defoliator of the Fir forest; consequently, considerable interest attends the synthesis of these two pheromones. A number of syntheses of these two pheromones have been reported3 amongst which is one of our synthesis using N,N-dimethyl acetone 4 hydrazone as key intermediate. 相似文献
47.
An efficient and convenient conversion of aldoximes and ketoximes to the corresponding carbonyl compounds with tetrameric DABCO–bromine complex is reported. 相似文献
48.
49.
Benzoyl peroxide (BPO) is primarily used in the treatment of mild to moderate acne. However, its application is associated with skin irritation. It has been shown that encapsulation and controlled release of BPO could reduce the side effect while also reducing percutaneous absorption when administered to the skin. The aim of the present investigation was to design and formulate an appropriate encapsulated form of BPO, using microsponge technology, and explore the parameters affecting the morphology and other characteristics of the resultant products employing scanning electron microscopy (SEM). Benzoyl peroxide particles were prepared using an emulsion solvent diffusion method by adding an organic internal phase containing benzoyl peroxide, ethyl cellulose and dichloromethane into a stirred aqueous phase containing polyvinyl alcohol (PVA). Different concentrations of BPO microsponges were incorporated in lotion formulations and the drug release from these formulations were studied. The SEM micrographs of the BPO microsponges enabled measurement of their size and showed that they were spherical and porous. Results showed that the morphology and particle size of microsponges were affected by drug:polymer ratio, stirring rate and the amount of emulsifier used. The results obtained also showed that an increase in the ratio of drug:polymer resulted in a reduction in the release rate of BPO from the microsponges. The release data showed that the highest and the lowest release rates were obtained from lotions containing plain BPO particles and BPO microsponges with the drug:polymer ratio of 13:1, respectively. The kinetics of release study showed that the release data followed Peppas model and the main mechanism of drug release from BPO microsponges was diffusion. 相似文献
50.
Sovan Mitra Andreas Karathanasopoulos Georgios Sermpinis Christian Dunis John Hood 《European Journal of Operational Research》2015
The role of decision support systems in mitigating operational risks in firms is well established. However, there is a lack of investment in decision support systems in emerging markets, even though inadequate operational risk management is a key cause of discouraging external investment. This has also been exacerbated by insufficient understanding of operational risk in emerging markets, which can be attributed to past operational risk measurement techniques, limited studies on emerging markets and inadequate data. 相似文献