摘要:
2-Acylfuran derivatives ##STR1## (R: alkyl, phenyl, etc.; R.sub.1 : H, alkyl) are prepared in high yield by reaction, in the presence of a boron trifluoride complex catalyst, of a furan compound ##STR2## (X: H, Cl, Br; Y: Cl, Br) or with RCOOH in the presence of (XYCHCO).sub.2 O.
摘要翻译:2-呋喃基衍生物通过在三氟化硼配合物催化剂的存在下,通过在呋喃化合物(X)(X)中的反应制备高收率的(R:烷基,苯基等; R 1:H,烷基) :H,Cl,Br; Y:Cl,Br)或与RCOOH在(XYCHCO)2 O存在下反应。
摘要:
Acylaromatic compounds ##STR1## (Q: aromatic compound residue; R: straight, branched or cyclic aliphatic group, aromatic group or araliphatic group) are prepared in high yield by a reaction, in the presence of a boron trifluoride complex catalyst, of an aromatic compound with ##STR2## (X: H, Cl, Br; Y: Cl, Br) or with RCOOH in the presence of (XYCHCO).sub.2 O.
摘要:
A process for preparing an optically active cyclopentenone of the formula: ##STR1## wherein R is a hydrogen atom or a lower alkyl group and n is an integer of 4 to 8, which comprises contacting a dl-cyclopentenone ester of the formula: ##STR2## wherein R and n are each as defined above and R' is a lower alkyl group optionally substituted with halogen on an enzyme having a capability of hydrolyzing selectively either one of the d- or l-form isomer in the dl-cyclopentenone ester (II) in an aqueous medium for asymmetric hydrolysis.
摘要:
Process for preparing haloketo acid derivatives [I]: ##STR1## wherein R is H or C.sub.1-6 alkyl, and X is chlorine or bromine, which comprises reacting .beta.-oxo-acid ester [II]: ##STR2## wherein R.sup.1 is H or C.sub.1-6 alkyl, R.sup.2 is C.sub.1-5 alkyl or OR.sup.3 (R.sup.3 is C.sub.1-6 alkyl), and X is the same as above, with nitrosating agent [IV]:ONOR.sup.4 [IV]wherein R.sup.4 is H, alkyl, halogen or SO.sub.3 H to give 7-halo-2-hydroxyminoheptanoic acid ester [III]: ##STR3## wherein R.sup.1 and X are the same as above, following by reacting the product with aldehyde or ketone; and intermediates therefor, and process for preparing said intermediates. Said haloketo acid derivatives are useful as intermediate for synthesis of cilastatin, which is useful as medicament, especially as dehydropeptidase inhibitor.
摘要:
Process for preparing haloketo acid derivatives [I]: ##STR1## wherein R is H or C.sub.1-6 alkyl, and X is chlorine or bromine, which comprises reacting .beta.-oxo-acid ester [II]: ##STR2## wherein R.sup.1 is C.sub.1-6 alkyl, R.sup.2 is C.sub.1-5 alkyl or OR.sup.3 (R.sup.3 is C.sub.1-6 alkyl), and X is the same as above, with nitrosating agent [IV]:ONOR.sup.4 [IV]wherein R.sup.4 is H, alkyl, halogen or SO.sub.3 H to give 7-halo-2-hydroxyiminoheptanoic acid ester [III]: ##STR3## wherein R.sup.1 and X are the same as above, followed by reacting the product with aldehyde or ketone; and intermediates therefor, and process for preparing said intermediates. Said haloketo acid derivatives are useful as intermediate for synthesis of cilastatin, which is useful as medicament, especially as dehydropeptidase inhibitor.
摘要:
An improved process for preparing an optically active 4-hydroxycyclopentenone of the formula: ##STR1## wherein R is a lower alkyl, the symbol means double bond or triple bond, and the * marked carbon is an asymmetric carbon, and the corresponding racemic 4-hydroxycyclopentenone, which are useful as an intermediate for preparing medicinal or agricultural products, particularly pharmaceutically active prostaglandins, and intermediates for preparing the optically active and/or racemic 4-hydroxycyclopentenone.
摘要:
Acetone having a markedly low content of aldehydes is recovered from an aqueous rectification residue brought about by rectification of crude acetone carried out after one crude acetone having been alkali-treated or while an alkali or an aqueous solution thereof being added to the crude acetone, by mixing the aqueous rectification residue with an alkali, neutralizing the mixture to a pH of 4 to 9, and then subjecting the resulting mixture to distillation to obtain acetone as a distillate.
摘要:
A fuel injection control system is provided. The fuel injection control system comprises a first injector and a second injector positioned upstream of the first injector; a memory section which contains a map for defining a correspondence between a running state of an engine and first and second fuel injection ratios; a fuel injection ratio setting section for setting the first fuel injection ratio as a first set value and the second fuel injection ratio as a second set value; and a fuel injection ratio compensation section for making compensation such that the first set value is greater than a value of the first fuel injection ratio derived from the map, when a condition in which the second fuel injection ratio read out from the map is greater in magnitude than a predetermined determination criterion is met.
摘要:
A vehicle including an engine, a tilting sensor configured to detect that a vehicle body of the vehicle has been tilted a predetermined angle or larger, a driving state sensor configured to detect a driving state of the vehicle using a component other than the tilting sensor, and a determiner configured to determine whether or not to stop the engine, based on a signal received from the tilting sensor, and a signal received from the driving state sensor.
摘要:
A fuel injection control system is provided. The fuel injection control system comprises a first injector and a second injector positioned upstream of the first injector; a memory section which contains a map for defining a correspondence between a running state of an engine and first and second fuel injection ratios; a fuel injection ratio setting section for setting the first fuel injection ratio as a first set value and the second fuel injection ratio as a second set value; and a fuel injection ratio compensation section for making compensation such that the first set value is greater than a value of the first fuel injection ratio derived from the map, when a condition in which the second fuel injection ratio read out from the map is greater in magnitude than a predetermined determination criterion is met.