摘要:
Periplanone-B analogue of (4E, 8R, 9R, 10R)-8,9-epoxy-5-methyl-10,10-methylene-oxy-4-cyclodecen-1-one, suitable as cockroach attractant can be prepared by reacting 6-methyl-2,6-cyclodecadien-1-one with a silylating reagent under the presence of a basic catalyst to form a silyldienol ether, reacting the resultant ether with an organic peracid to obtain (2Z, 6E)-10-hydroxy-6-methyl-2,6-cyclodecadien-1-one, reacting the resultant product with a peroxide under the presence of a basic catalyst after protecting hydroxy groups thereof with protection groups to obtain an epoxide, reacting the epoxide with chloromethyl lithium or dimethyl sulfonium methylide thereby introducing a spiroepoxy group and then removing the protection groups, to obtain (1S, 4E, 8R, 9R, 10S)-8,9-epoxy-5-methyl-10,10-methyleneoxy-4-cyclodecen-1-ol and, further, oxidizing the resultant product with a chromic acid type or dimethyl sulfoxide type oxidizing agents.
摘要:
The present invention provides a gas-insulated electric apparatus which includes: a vertically-arranged gas insulation main tank; a first gas insulation branch pipe connected to and making right angle with the gas insulation main tank; a second gas insulation branch pipe connected to and making right angle with the gas insulation main tank; a breaker manipulator which is arranged on an upper side of the main tank, a feeder-side current transformer which is incorporated in the first gas insulation branch pipe; a voltage transformer arranged on the first gas insulation branch pipe; and an arrestor arranged on the first gas insulation branch pipe and connected with the feeder.
摘要:
Levoglucosenone is prepared by reaction sequence using 1,6-anhydro-.beta.-D-galactopyranose as a starting material. First, the starting material is reacted with ortho formate, obtaining an ortho ester of said starting material. Then, the ortho ester is placed under the conditions for a reductive elimination reaction of the ortho formate part of said ortho ester, thereby converting said ortho ester to a 1,6-anhydro-3,4-dideoxy derivative. The dideoxy derivative is placed under the conditions for oxidation of the hydroxy group of said dideoxy derivative, thereby forming levoglucosenone.
摘要:
The present invention provides a gas-insulated electric apparatus which includes: a vertically-arranged gas insulation main tank; a first gas insulation branch pipe connected to and making right angle with the gas insulation main tank; a second gas insulation branch pipe connected to and making right angle with the gas insulation main tank; a breaker manipulator which is arranged on an upper side of the main tank, a feeder-side current transformer which is incorporated in the first gas insulation branch pipe; a voltage transformer arranged on the first gas insulation branch pipe; and an arrestor arranged on the first gas insulation branch pipe and connected with the feeder.
摘要:
Tobacco material is reduced in stimulus and pungency in its smoking stage by decreasing a content of a colored acidic water-soluble polymer substance.
摘要:
An insulating strip layer is provided in the middle portion of an isolating zone which isolates electronic element regions from each other. A platinum layer is formed and sintered, whereby platinum silicide layers are obtained between the insulating strip layer and the electronic element regions. A silicon nitride film is formed and etched by plasma. The plasma etches the silicon nitride film and selectively etches the wafer through the gaps between the platinum silicide layers and layers adjacent thereto whereby grooves are obtained in the isolating zone. A crack which may be caused in the cutting or dicing process is stopped at the grooves.