摘要:
The present invention relates to a method for producing an optically active 3-aminopiperidine or salt thereof. In the method, a racemic nipecotamide is stereoselectively hydrolyzed to obtain an optically active nipecotamide and an optically active nipecotic acid in the presence of an enzyme source derived from an organism, and then the optically active nipecotamide is derived into an optically active aminopiperidine or salt thereof by aroylation, Hofmann rearrangement, deprotection of the amino group and further deprotection; or the optically active nipecotamide is derived into an optically active aminopiperidine or salt thereof by selective protection with BOC, Hofmann rearrangement and further deprotection. It is possible by the present invention to produce an optically active 3-aminopiperidine or salt thereof useful as a pharmaceutical intermediate from an inexpensive and easily available starting material by easy method applicable to industrial manufacturing.
摘要:
The present invention relates to a method for producing an optically active 3-aminopiperidine or salt thereof. In the method, a racemic nipecotamide is stereoselectively hydrolyzed to obtain an optically active nipecotamide and an optically active nipecotic acid in the presence of an enzyme source derived from an organism, and then the optically active nipecotamide is derived into an optically active aminopiperidine or salt thereof by aroylation, Hofmann rearrangement, deprotection of the amino group and further deprotection; or the optically active nipecotamide is derived into an optically active aminopiperidine or salt thereof by selective protection with BOC, Hofmann rearrangement and further deprotection. It is possible by the present invention to produce an optically active 3-aminopiperidine or salt thereof useful as a pharmaceutical intermediate from an inexpensive and easily available starting material by easy method applicable to industrial manufacturing.
摘要:
A 2-formylacetic ester derivative represented by the general formula (5) is provided: where R4 represents an alkyl group having 2 to 6 carbon atoms; R5 represents an alkyl group having 1 to 10 carbon atoms; and X represents H, Li, Na or K.
摘要:
The present invention provides a simple industrial process for producing an L- or D-optically active α-methylcysteine derivative or its salt, which is a useful pharmaceutical intermediate, from readily available, inexpensive raw materials. In a process for producing an L- or D-optically active α-methylcysteine derivative or its salt, a racemic N-carbamoyl-α-methylcysteine derivative or its salt is D-selectively cyclized with hydantoinase to produce a D-5-methyl-5-thiomethylhydantoin derivative or its salt and an N-carbamoyl-α-methyl-L-cysteine derivative or its salt, which are then subjected to deprotection of the amino group and the sulfur atom, and hydrolysis.
摘要:
The present invention has been made to reduce the size and thickness of a multibeam antenna capable of switching the directivity in multi directions. The present invention provides a multibeam antenna including an antenna element array including one or more feed element and N (N: natural number) parasitic elements, wherein the electrical length of one or more parasitic elements are made variable.
摘要:
A tandem type master cylinder is disclosed having a housing with a through-bore defining an intermediate portion and opposed end portions. The diameter of each end portion is larger than the diameter of the intermediate portion, and the junctures between the end portions and the intermediate portion define step parts within the housing. Seal assemblies are positioned within the housing at the step junctures formed by the intermediate portion and the end portions and are retained in position by a plug secured within each end portion. Primary and Secondary pistons are disposed for guided movement along the intermediate portion of the housing, and return springs are provided within the housing for urging each piston to its initial rest position.
摘要:
Improvement in an annular seal for use in a hydraulic actuator is obtained in accordance with the present invention, which annular seal is of the type including fitting holes to be inserted by projections formed in a piston guide and is adapted to be mounted between a piston guide sleeve and the piston guide, by the provision of annular projections extending in an annular shape and in the axial direction of the seal in the inner and outer circumferential portions with respect to the location of the fitting holes or in the circumferential area of the piston guide corresponding to that circumferential portions.
摘要:
A brake booster includes a plunger which defines a valve mechanism. A stop member is provided to prevent the withdrawal of the plunger, and structure is provided to prevent the disengagement of the stop member from a valve body. Specifically, the valve body is formed with a detent, and a retainer which supports the stop member is formed with a detent which is engageable with the detent on the valve body. The retainer is disposed externally of the stop member, and the detents on both the valve body and the retainer are effective, when engaged, to prevent the disengagement of the stop member from the valve body.
摘要:
In a discharge system that outputs DC power from a vehicle battery to the outside, improved safety is obtained during discharge of the battery. A discharge system includes an electric car having a battery unit mounted thereon, and a discharge device that discharges the battery unit. The electric car includes a connector to which the discharge device is connected, and a power line that connects the connector and the battery unit to each other. In the power line, switches and switching elements are provided. The switches render the power line conducting upon permission from the discharge device and a battery management unit. The switching elements adjust a current flowing in the power line when the battery unit is discharged.
摘要:
In the conventional vehicle control device, since a detection timing of turn is late, at the time of making the change of gear ratio based the detection timing, a sense of discomfort is brought to a driver. Moreover, steering wheel angle sensor, yaw rate sensor or lateral acceleration sensor is very expensive, resulting in the cost increase of the vehicle control devices. From information regarding a steering force that can be obtained from an electric power steering device, a turn intention of a driver is detected, and based the turning intention, the change of gear ratio is conducted.