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The ingestion of giant freshwater prawn, Chinese prawn and giant tiger prawn had continuity and the ingestion high peak occurred at night. Light and temperature had significant effects on the daily ingestion rate (DIR) of giant freshwater prawnMacrobrachium rosenbergii. Red light and blue light favorably induced favorable ingestion. In the adaptive range of temperature, the DIR increased with rising temperature and feeding frequency, but decreased with rising body weight.

Tropinone (6) was deprotonated with lithium diisopropylamide and with chiral lithium amides (18–24) and the resulting enolates (two enantiomers) were treated with electrophiles. The aldol reaction with benzaldehyde and deuteration were both diastereoselective. The former yielded only one isomer (exo, anti) of the aldol 8a; the latter proceeded from the exoface. This selectivity permitted us to probe the deprotonation of tropinone with lithium amides; it was concluded that the reaction involves predominantly the exoaxial protons. The reaction of tropinone enolate with ethyl chloroformate led, via a ring opening, to the cycloheptenone derivative 9. The reaction with methyl cyanoformate yielded, in the presence of silver acetate and acetic acid, the β-ketoester 8b; however, in the absence of these additives, and especially when 12-crown-4 was added to the enolate, a ring opening leading to the pyrrolidine derivative 10occurred instead. Deprotonation of tropinone with chiral lithium amides proceeded with modest enantioselectivity. A synthesis of non-racemic anhydroecgonine via this strategy allowed establishing the absolute stereochemistry of deprotonation.

A system for in situ regeneration of SmI 2from SmI 3is described which allows the annulation of ketones to γ-lactones, the deoxygenation of oxiranes to olefins and radical π-cyclization to be conducted with 10 mole % SmI 2.

Abstract: This study deals with the hydrochemical state and management measures for the intermediate culture pond for Chinese prawn (Penaeus orientalis) juveniles. The test result showed that the intermediate culture of Chinese prawn juvenile can be advanced to around March 20 in the Shanghai area if they are cultured in ponds in simple greenhouses of plastic knitting cloth. The density of juveniles introduced was about 35 million per hectare, survival was up to 55%.

2,6-Bis(triisopropylsilyl)pyridine (1) has been synthesized from 2,6-dibromopyridine. It is a very weak base in water since it does not dissolve in 6N hydrochloric acid, but does undergo protonation in nonaqueous media by triflic acid.

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.