摘要:
A process which comprises converting a α-amino acid ester into the corresponding imine to thereby protect the amino group of the ester, reacting the imine with a halomethyllithium to form an N-protected α-amino halomethyl ketone, and treating this N-protected α-amino halomethyl ketone with an acid to obtain a α-amino halomethyl ketone. This process is suitable for industrial production and permits economical and efficient production of α-amino halomethyl ketones and compounds related thereto.
摘要:
A process for preparation of gabapentin hydrochloride by converting 1,5-dicyano-2,4-dioxo-3-azaspiro[5,5]-undecane into 1,5-diaminoformyl-2,4-dioxo-3-azaspiro[5,5]-undecane at a temperature of 65°C to 85°C in the presence of a strong acid, and then carrying out Hofmann rearrangement under an alkaline condition. The starting material of the process is readily available. The process is simple, and can reduce the purification procedure of intermediates, reduce production cost, and obtain product with higher purity.
摘要:
Synthesis of 2,5-bis-diamine-[l,4]benzoquinonic derivatives having the general formula (I), products and intermediates of said synthesis; the synthesis involves the use of p-benzoquinones having the general formula (IX) and diamines having the general formula (XI).
摘要:
Provided is a process for the preparation of N-monosubstituted β-aminoalcohol sulfonates of formula (Ia), (Ib) wherein R1 is C6-20 aryl or C4-12 heteroaryl, each optionally being substituted with one or more halogen atoms and/or one or more C1-4 alkyl or C1-4 alkoxy groups, R2 is C1-4-alkyl or C6-20 aryl, each aryl optionally being substituted with one or more halogen atoms and/or one or more C1-4-alkyl or C1-4-alkoxy groups, and wherein R3 is selected from the group consisting of C1-18 alkyl, C6-20 cycloalkyl, C6-20 aryl and C7-20 aralkyl residues, comprising the steps of a) reacting a methyl ketone, a primary amine, formaldehyde and a sulfonic acid, at a pressure above 1.5 bar, optionally in a organic solvent, said organic solvent optionally containing water, to afford N-monosubstituted β-aminoketone sulfonates of formula (II), wherein R1, R2 and R3 are as defined above, and b) asymmetrically hydrogenating said sulfonates in the presence of a base and a catalyst, comprising a transition metal and a diphosphine ligand, in a polar solvent, optionally in the presence of water.
摘要:
A 5-aminolevulinic acid salt which is useful in fields of microorganisms, fermentation, animals, medicaments, plants and the like; a process for producing the same; a medical composition comprising the same; and a plant activator composition comprising the same.
摘要:
Novel amine derivatives having an excellent antimycotic effect represented by general formula (1) below or salts thereof are provided. [in the formula (1), R 1 represents a C 1-5 alkyl group which may be halogenated, R 2 represents 4-(1,1-dimethylalkyl)benzyl group, 4-(1-methyl-1-phenylethyl)benzyl group, or 1- or 2- naphthylmethyl group; R 3 represents oxygen atom or a methylene group which may be substituted by a C 1-4 alkyl group; and R 4 represents 1- or 2 naphthyl group or a phenyl group which may be substituted.