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261.
Karuturi Rajesh Vangaru Suresh Jondoss Jon Paul Selvam Dokuburra Chanti Babu Yenamandra Venkateswarlu 《Helvetica chimica acta》2010,93(1):147-152
A simple and highly efficient stereoselective total synthesis of (11β)‐11‐methoxycurvularin ( 5 ), a polyketide natural product, was achieved. The synthesis commenced with a Cu‐mediated regioselective opening of (2S)‐2‐methyloxirane ( 6 ) and comprised a Keck asymmetric allylation and intramolecular Friedel–Crafts acylation as key steps (Scheme 2). 相似文献
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267.
Sorption properties of oxides IX: Effect of anions on the sorption of uranium (VI) on hydrous oxides
Effect of anions such as nitrate, chloride, sulphate and carbonate on the sorption of U(VI), from aqueous solutions on hydrous
oxides of Ti(IV), Ce(IV) Zr(IV) and Th(IV) has been studied. The sorption of U(VI) is markedly reduced in the presence of
anions, like carbonate, whichform strong complexes with UO
2
2
+ in solution. The results are explained in terms of a competition for free UO
2
2
+ between surface hydroxyl groups and ligands (anions) present in solution. The sorption of U(VI) on these hydrous oxides was
also studied from a bicarbonatecarbonate mixture. Sorption was less under conditions when tricarbonate complex of U(VI) was
formed, but increased at higher pH values (>9), presumably due to the formation and sorption of hydroxo complexes of U(VI). 相似文献
268.
Baggu Chinnababu Sudina Purushotham Reddy Kunuru Venkatesham Dasireddi Chandra Rao Yenamandra Venkateswarlu 《Helvetica chimica acta》2014,97(5):613-618
A simple and highly efficient synthetic route has been developed for synthesis of 1‐(4‐hydroxyphenyl)nonadecane‐3,5‐diol ( 1 ). The two stereogenic centers were generated by employing proline asymmetric α‐hydroxylation (MacMillan α‐hydroxylation), Jacobsen's hydrolytic kinetic resolution (HKR), and, finally, Yamaguchi oxirane opening as key steps (Scheme 2). 相似文献
269.
Shaik Thaslim Basha Hasti Sudhamani Syed Rasheed Nagam Venkateswarlu Tartte Vijaya 《Phosphorus, sulfur, and silicon and the related elements》2016,191(10):1339-1343
A series of diethyl/ethylphenyl {2-(benzo[d]thiazol-2-yl)phenylamino}phosphonates and phosphinates were synthesized under microwave irradiation and neat conditions via Kabachnik-Fields reaction in high yields (80%–93%). The compounds were screened for antimicrobial and antioxidant properties. A few compounds showed effective antibacterial and antifungal activities at MIC value 12.5 μg/mL as compared with the standard at MIC value 6.25 μg/mL. 相似文献
270.