Abstract: Provided is a process for preparing 4-borono-L-phenylalanine, which has steps of: reacting N-protected (S)-4-halophenylalanine of formula (I), a boronating agent and an organolithium to obtain a reaction mixture, wherein the reaction mixture comprises N-protected (S)-4-boronophenylalanine of formula (II) and the R group represents a protecting group; isolating the N-protected (S)-4-boronophenylalanine from the reaction mixture; deprotecting the R group of the N-protected (S)-4-boronophenylalanine to obtain L-BPA.

Abstract: Provided is a process for preparing 4-borono-L-phenylalanine, which has steps of: reacting N-protected (S)-4-halophenylalanine of formula (I), a boronating agent and an organolithium to obtain a reaction mixture, wherein the reaction mixture comprises N-protected (S)-4-boronophenylalanine of formula (II) and the R group represents a protecting group; isolating the N-protected (S)-4-boronophenylalanine from the reaction mixture; deprotecting the R group of the N-protected (S)-4-boronophenylalanine to obtain L-BPA.

Abstract: Provided is a compound of the following formula (I) for preparing 4-(10B)borono-L-phenylalnine: wherein R group represents a protecting group and is selected from the group consisting of: tert-butoxycarbonyl (Boc) group, trityl (Trt) group, 3,5-dimethoxyphenylisopropoxycarbonyl(Ddz) group, 2-(4-Biphenyl)isopropoxycarbonyl (Bpoc) group, and 2-nitrophenylsulfenyl (Nps) group, and the compound has a 10B purity higher than or equal to 98% and an enantiomeric excess higher than or equal to 99%.

Abstract: The method in accordance with the present invention has: mixing E2M, an organic solvent, a weak base, sodium dithionite, and a phase transfer catalyst to obtain an E2M mixture solution; heating the E2M mixture solution and adding water to obtain a heated E2M aqueous solution having an organic layer; and extracting the organic layer from the heated E2M aqueous solution, and condensing and drying the organic layer to obtain donepezil. Employing sodium dithionite as a reducing agent improves safety over hydrogen gas used in conventional methods and lowers the cost in contrast to the conventional noble metal catalysts that are extremely expensive. Furthermore, the method of the present invention requires only 60 minutes of reaction time to synthesize donepezil with a promising yield more than 85%, which greatly raises the efficiency and economic value of the manufacture of donepezil.

Abstract: The method in accordance with the present invention has: mixing E2M, an organic solvent, a weak base, sodium dithionite, and a phase transfer catalyst to obtain an E2M mixture solution; heating the E2M mixture solution and adding water to obtain a heated E2M aqueous solution having an organic layer; and extracting the organic layer from the heated E2M aqueous solution, and condensing and drying the organic layer to obtain donepezil. Employing sodium dithionite as a reducing agent improves safety over hydrogen gas used in conventional methods and lowers the cost in contrast to the conventional noble metal catalysts that are extremely expensive. Furthermore, the method of the present invention requires only 60 minutes of reaction time to synthesize donepezil with a promising yield more than 85%, which greatly raises the efficiency and economic value of the manufacture of donepezil.

Abstract: The present invention discloses a new process for the synthesis of tamsulosin and its aralkylamine derivatives, especially (R)-(?)-5-{2-[2-(2-alkoxyphenoxy) ethylamino]propyl}-2-alkoxybenzenesulfonamides having the following formula 1 (where R1 and R2 represent C1-C4 alkyl groups) and their hydrochloride thereof, and other various pharmaceutical used salts. Tamsulosin hydrochloride (R1=Et, R2=Me, in its hydrochloride salt form) is an antagonist of ?-A adrenoceptors in the prostate. Tamsulosin•HCl occurs as white crystals, which melt with decomposition at approximately 230° C. It is sparingly soluble in water and in methanol, slightly soluble in glacial acetic acid and in ethanol, and practically insoluble in ether.