摘要:
Disclosed is a process for the preparation of a 4-substituted azetidinone derivative, which comprises reacting an azetidinone derivative and an amide compound in the presence of a magnesium compound such as those represented by the following formulas (II): and (IV): represented by the following formula (III): MgR5R6 (III) wherein R5 represents a C1-12 alkyl group, a C2-5 alkenyl group, a 5- to 8-membered alicyclic group which may be substituted by a lower C1-4 alkyl group, a phenyl group which may be substituted by a lower C1-4 alkyl group, a lower C1-4 alkoxy group or a halogen atom or a benzyl group which may be substituted by a lower C1-4 alkyl group, a lower C1-4 alkoxy group or a halogen atom, and R6 represents a halogen atom, a methanesulfonyloxy group, a benzenesulfonyloxy group, a p-toluenesulfonyloxy group, a trifluoromethanesulfonyloxy group, an acetoxy group which may be substituted by a halogen atom or a cyano group or an OR7 group (R7 representing a lower C1-4 alkyl group, a substituted or unsubstituted phenyl group or a substituted or unsubstituted benzyl group). The process provides an industrially excellent process for the preparation of a 4-substituted azetidinone derivative which permits the selective preparation of an intermediate for the synthesis of a carbapenem antibacterial agent having a desired 1-&bgr;′ configuration.
摘要:
A method for manufacturing (3S,4R)-4-[(R)-1′-formylethyl]azetidin-2-one derivatives represented by formula (3) wherein R1 represents a hydrogen atom or a protective group, through asymmetric hydroformylation of 4-vinylazetidin-2-one represented by formula (1) wherein R1 has the same meaning as described above; in the presence of a rhodium complex and a (2S,4S)-diphosphine compound represented by formula (2) wherein R2 represents a phenyl group which may be substituted with 1-5 substituent(s) selected from a lower alkyl group, a lower alkoxy group, and a halogen atom. By use of both an inexpensive optically active diphosphine compound and a rhodium complex as catalysts, intermediate compounds important for carbapenem antibiotics can be manufactured with high selectivity and efficiency.
摘要:
A phosphine-phosphinite compound represented by formula (I): ##STR1## wherein R.sup.1 and R.sup.2, which may be the same or different, each represent a substituted or unsubstituted phenyl group or a substituted or unsubstituted naphthyl group, and a process for preparing a 4-�(R)-1'-formylethyl!azetidin-2-one derivative using the compound (I). The compound (I), either in combination, or as a complex, with a transition metal compound, is useful as a catalyst for asymmetric hydroformylation and makes it possible to easily synthesize an important intermediate for carbapenem antibiotics or a precursor thereof at high regioselectivity and diastereo-selectivity.
摘要:
A slide member is slidable along a slide rail provided at a vehicle-body side portion. When lock pawls provided at the slide member are engaged with the slide rail, the slide member is locked. The slide member is unlocked by operating an operation cable connected to the lock pawls. The operation cable is fitted to a fitting portion of an attachment bracket connected to the slide rail. A portion from a fixed portion fixed to the fitting portion to a movable portion (one end portion) extends through a region where a non-contact portion is disposed, and does not contact the non-contact portion. The movable portion is connected to the slide member and moved integrally with the slide member.
摘要:
A silicon-based thin film depositing apparatus, including a plurality of transparent electrodes disposed to face corresponding counter electrodes with a space therebetween. Subsequently, while injecting a raw material gas from raw material gas injection orifices toward the supporting electrodes and also injecting a barrier gas from barrier gas injection orifices in the same direction as the direction in which the raw material gas is injected, the gases are discharged from a gas outlet, and thereby, the pressure in a chamber is controlled to a pressure of more than 1 kPa. Then, a DC pulse voltage is applied to each counter electrode to deposit a silicon-based thin film. A DC pulse voltage is applied to perform discharge. Therefore, even in a state where the distance between the electrodes is increased, plasma can be generated efficiently, and the in-plane distribution of film thickness can be improved.
摘要:
A pulsed power supply includes a DC power source, and a transformer and a switch which are connected in series with each other across the DC power source. The pulsed power supply operates to produce a plurality of high-voltage pulses in a repetition of cycles in each of which an induced energy is stored in the transformer when the switch is turned on and a high-voltage pulse is generated across a secondary winding of the transformer when the switch is turned off. The current flowing through the primary winding of the transformer is controlled to keep its peak value constant. The pulsed power supply further includes a current detector for detecting the current flowing through the primary winding of the transformer, and a third circuit for turning off the switch when the current detected by the current detector reaches the peak value.
摘要:
A direct current pulse voltage is applied on a treatment gas to generate a discharge plasma. The duty ratio of the direct current pulse voltage is controlled within the range of 0.0001% or more and 8.0% or less. The rise time of the direct current pulse voltage is controlled in the range of not lower than 0.1 V/nsec and not higher than 10000 V/nsec. Alternatively, a positive pulse and a negative pulse are applied from a single power source for performing the discharge plasma and the impurity implantation.
摘要:
A pulse power source comprises a first circuit, a second circuit, a transformer for coupling the first circuit and the second circuit, and a switching controller. The second circuit comprises a third semiconductor switch connected in series with a secondary winding of the transformer. The third semiconductor switch is connected in such a direction that a voltage generated in the second circuit is reverse-biased during a period in which the second semiconductor switch is turned on. A gate amplifier for forming a control signal from the switching controller into a pulse and outputting the pulse as a pulse signal is connected between a gate terminal and a cathode terminal of the third semiconductor switch.
摘要:
Metallic particle layers with metallic domains being arranged therein each at a predetermined space within a horizontal plane are laminated at an appropriate distance in the vertical direction in a dielectric layer. The distance ΔW between each of the metallic domains may be controlled by controlling the growth of metallic particles for the horizontal direction and the distance ΔL between the metallic particle layers may be controlled by controlling the thickness of the dielectric layer to be laminated for the vertical direction, so that the effect of field enhancement by plasmon resonance is improved by satisfactory control for the plasmon resonance in the direction of the thickness and in the direction orthogonal thereto.
摘要:
The Problem to Be Solved: To provide a producing method of an optically active β-amino acid useful as intermediate for the production of medicines, agricultural chemicals and physiologically active substances, by means of a catalytic and asymmetric synthesis method of high performance and a high enantiomeric excess, without requiring additional procedures such as introduction and removal of protecting group and so on. Means to Solve the Problems: A producing method of an optically active β-amino acids which comprises subjecting an enamine to an asymmetric hydrogenation.