- Method for synthesizing ritodrine hydrochloride
-
The invention discloses a method for synthesizing ritodrine hydrochloride. The method comprises that p-chlorobenzaldehyde and pyruvic acid as substrates undergo a catalytic reaction, the product is purified to form (R)-1-(4-chlorophenyl)-1-hydroxypropane-2-one, the (R)-1-(4-chlorophenyl)-1-hydroxypropane-2-one and ammonium formate as substrates undergo a catalytic reaction, the product is purifiedto form (1R, 2S)-2-amino-1-(4-chlorophenyl)-1-propanol, the (1R, 2S)-2-amino-1-(4-chlorophenyl)-1-propanol and LiOH. H2O undergo a reaction to produce 4-((1R, 2S)-2-amino-1-hydroxypropyl)phenol and 4-((1R, 2S)-2-amino-1-hydroxypropyl)phenol and 4-(2-chloroethanol)phenol undergo a reaction to produce ritodrine hydrochloride. The method realizes a low cost, utilizes mild reaction conditions and issuitable for industrial production.
- -
-
Paragraph 0045; 0047; 0049
(2018/04/01)
-
- A NOVEL METHOD FOR SYNTHESIS OF OPTICALLY PURE BETA-AMINO ALCOHOLS
-
A method for the preparation of β-amino alcohol of formula (III) in which R1 is Ph, (substituted) Ph, R2 is C1-8 alkyl or C4-6 cyclo alkyl, R3 = R4R5CHNH2 where, R4 = H, C1-8 alkyl, C4-6 cyclo alkyl, or - COOR6 (R6=C1-C8 alkyl); R5 = (subst) aryl], the method including subjecting an α-hydroxy ketone of formula (I) in which R1 and R2 are as defined above is reacted with a chiral amine of formula R3NH2 where R3 = R4R5CH- where, R4 = H, C1-8 alkyl, C4-6 cycloalkyl, or - COOR6 (R6=C1-8 alkyl), R5 = (subst) aryl] to produce a compound of formula (II) in which R1, R2 and R3 are as defined above, followed by reduction to form the compound of formula (III).
- -
-
-
- PROCESS FOR PRODUCING OPTICALLY ACTIVE s-AMINO ALCOHOL
-
A process for easily producing an optically active β-amino alcohol useful as a pharmaceutical intermediate from an inexpensive, readily available starting material is provided. A readily available α-substituted ketone is reacted with an optically active amine to yield a diastereomer mixture of an optically active α-substituted aminoketone. One of the diastereomers is isolated optionally after the diastereomers are converted to salts with an acid. The optically active α-substituted aminoketone or a salt thereof thus isolated was stereoselectively reduced to yield an optically active β-substituted amino alcohol. The optically active β-substituted amino alcohol is subjected to hydrogenolysis to produce an optically active β-amino alcohol or a salt thereof.
- -
-
Page/Page column 22
(2008/06/13)
-
- PHENOL DERIVATIVES AND METHOD OF USE THEREOF
-
The present invention provides novel phenol derivatives represented by the formula: wherein the carbon atom marked with (S) represents a carbon atom in S configuration; Z represents the group represented by the formula: or the formula: wherein the carbon
- -
-
Page/Page column 5; 6
(2010/02/11)
-
- Antimitotic agents. Chiral isomers of ethyl [5-amino-1,2-dihydro-3-(4- hydroxyphenyl)-2-methylpyrido[3,4-b]pyrazin-7-yl]carbamate
-
Metabolism studies with ethyl [5-amino-1,2-dihydro-2-methyl-3- phenylpyrido[3,4-b]pyrazin-7-yl]carbamate (1) in mice were reported previously to give a hydroxylated metabolite, which was methylated to give a methoxy derivative. The metabolite and its deri
- Temple Jr.,Rener
-
p. 988 - 993
(2007/10/02)
-