摘要:
The invention concerns a method for preparing 4-hydroxyisoleucine diastereoisomers and enantiomers and derivatives thereof of general formula (I), characterized in that it consists in reducing an isoxazole derivative of formula (II) in conditions directly resulting in the derivatives of formula (I), or in obtaining at least a lactone of structure (III) in racemic form(s), or a enantiomerically enriched mixture, followed by opening, in basic conditions, in an aprotic or protic solvent, the desired lactone(s) and, optionally, separating the desired form. The invention is useful for preparing in particular (2S, 3R, 4S)-4-hydroxyisoleucine.
摘要:
The invention relates to a method for the synthesis of two isomers, at function OH, alone or in mixtures, of amino acids α or the derivatives thereof, having general formula (B), wherein: linkage C—O of the 4-position carbon (represented by symbol) denotes one or other of isomers III or IV, or mixtures thereof. Moreover, R1 and R2 represent: a hydrogen atom; or either R1 or R2 represents a hydrogen atom and the other substituent is a radical Ra, an acyl group —CORa, such as acetyl, or a functional group —COORa, —SO2Ra, —N (Ra, Rb), Ra and Rb, which are identical or different, representing a C1-C12 linear or branched alkyl radical, optionally substituted, an aryl group with one or more aromatic rings and heterocycles, comprising between 5 and 8C, optionally substituted, or aralkyl, the alkyl substituent and the aryl group being as defined above; or R1 and R2 both represent a substituent as defined above. R3 represents a hydrogen atom or Ra and R4 has the significance of Ra. The invention is characterised in that it comprises: the isomerisation of a compound having formula (I), wherein R1, R2, Ra, R3 and R4 are as defined above, such as to produce a compound having formula (II); and the reduction of the carbonyl function thereof which, depending on the catalytic system employed and the formula (I) compound used, produces one of the isomers having general formula (III) or (IV) or a mixture thereof having formula (B). The invention can be used for the synthesis of (2S, 3R, 4S)-4-hydroxyisoleucine.
摘要:
The invention concerns a method for preparing 4-hydroxyisoleucine diastereoisomers and enantiomers and derivatives thereof of general formula (I), characterized in that it consists in reducing an isoxazole derivative of formula (II) in conditions directly resulting in the derivatives of formula (I), or in obtaining at least a lactone of structure (III) in racemic form(s), or a enantiomerically enriched mixture, followed by opening, in basic conditions, in an aprotic or protic solvent, the desired lactone(s) and, optionally, separating the desired form. The invention is useful for preparing in particular (2S, 3R, 4S)-4-hydroxyisoleucine
摘要:
A method for selecting at least one catalyst from a catalyst library on the basis of the reactivity thereof in a chemical conversion process includes: (a) testing the catalytic activity of a first catalyst from said catalyst library with respect to a reaction medium containing, as the compounds to be converted, at least one reactivity probe having a labeling system and including at least one reaction unit capable of reacting in said chemical conversion; (b) analyzing the reaction medium after said catalytic test for the purpose of qualitatively and/or qualitatively characterizing the resulting compounds; (c) repeating steps (a) and (b) for at least one other catalyst in said library; and (d) comparing the analysis results for each catalyst in order to characterize at least one catalyst having the required reactivity in said chemical conversion.
摘要:
The invention relates to a method for creating a database enabling, in particular, the selection of at least one reaction-capable catalyst, comprising the following steps: a) preparing a number of different reaction media containing the same reactivity probe and each having at least one catalyst; b) analyzing, by means of an analytic method, each reaction medium after reaction, and; c) assigning, in the database, an analysis result according to step b) to the reactivity probe, this result characterizing different reaction products obtained from said reactivity probe. The database is a relational database containing: a first entity in which items of information relative to the reaction patterns listed in the data base are recorded; a second entity containing items of information relative to the state of bindings of at least one reaction pattern listed in the first entity; a third entity in which items of information associated with different reaction media are stored, and; at least one fourth entity in which items of information are stored that are linked to the analysis results of the reaction media at the end of a reaction.
摘要:
Drugs for preventing and/or treating progressive lesions after organ damage without inhibiting the function of the organ or the regeneration function thereof, by selectively regulating the induction of cytotoxic effecter macrophages which are induced into damaged organ tissues in response to chemokines or cytokines expressed depending on the type of the damaged organ tissues.
摘要:
The present invention relates to a method of transforming cells in which an appropriate quantity of nucleic acid fragments is introduced into the cells. The nucleic acid fragments are introduced in the form of a nucleic acid composition comprising a nitrogen-containing silicone, useful for compacting the nucleic acid fragments; the compositions comprise aggregates of nucleic acid fragments and silicones according to the invention.
摘要:
The invention concerns a method for functionalizing a phenolic compound bearing an electron-donor group, in said group para position, inter alia a method for the amidoalkylation of a phenolic compound bearing an electron-donor group, and more particularly, a phenolic compound bearing an electron-donor group preferably, in the hydroxyl group ortho position. The method for functionalizing in para position with respect to an electron-donor group carried by a phenolic compound is characterised in that the phenolic compound bearing an electron-donor group is subjected to the following steps: a first step which consists of protecting the hydroxyl group in the form of a sulphonic ester function; a second step which consists in reacting the protected phenolic compound with an electrophilic reagent; optionally, a third step deprotecting the hydroxyl group.
摘要:
The invention relates to a method for the synthesis of two isomers, at function OH, alone or in mixtures, of amino acids α or the derivatives thereof, having general formula (B), wherein: linkage C—O of the 4-position carbon (represented by symbol) denotes one or other of isomers III or IV, or mixtures thereof. Moreover, R1 and R2 represent: a hydrogen atom; or either R1 or R2 represents a hydrogen atom and the other substituent is a radical Ra, an acyl group —CORa, such as acetyl, or a functional group —COORa, —SO2Ra, —N (Ra, Rb), Ra and Rb, which are identical or different, representing a C1-C12 linear or branched alkyl radical, optionally substituted, an aryl group with one or more aromatic rings and heterocycles, comprising between 5 and 8C, optionally substituted, or aralkyl, the alkyl substituent and the aryl group being as defined above; or R1 and R2 both represent a substituent as defined above. R3 represents a hydrogen atom or Ra and R4 has the significance of Ra. The invention is characterised in that it comprises: the isomerisation of a compound having formula (I), wherein R1, R2, Ra, R3 and R4 are as defined above, such as to produce a compound having formula (II); and the reduction of the carbonyl function thereof which, depending on the catalytic system employed and the formula (I) compound used, produces one of the isomers having general formula (III) or (IV) or a mixture thereof having formula (B). The invention can be used for the synthesis of (2S, 3R, 4S)-4-hydroxyisoleucine.
摘要:
An object of the present invention is to provide a pharmaceutical agents for preventing and/or treating the progressive lesion after the organic damage without inhibiting organic function or regeneration function thereof, by selectively suppressing the induction of cytotoxic effector macrophages which are induced into the damaged organs in response to chemokines and cytokines which are expressed depending on the type of damaged organic tissues.