286930-02-7

Usage

Uses

Used in Pharmaceutical Industry:
(R) Fesoterodine is used as a treatment for Overactive Bladder (OAB) due to its potent muscarinic antagonist properties, which help in managing the symptoms of OAB. It is effective in improving the quality of life for patients suffering from this condition.
The recommended starting dose is 4 mg once daily, which may be increased to 8 mg once daily based on individual response and tolerability. Fesoterodine is rapidly and completely bioconverted to 5-HMT, which has a bioavailability of about 52%. Plasma concentrations of 5-HMT are proportional to the dose, and maximum plasma levels are reached after approximately 5 hours. No accumulation occurs after multiple-dose administration.

Originator

Schwarz Pharma (Germany)

Synthesis

The chemical synthesis of fesoterodine starts with the cyclization of 4-(hydroxymethyl)phenol with cinnamaldehyde by means of piperazine in refluxing toluene to produce 2-hydroxy-6-(hydroxymethyl)-4-phenyl-3,4-dihydro-2H-1- benzopyran, which is subjected to reductive amination with To Market, To Market 2008 605 diisopropylamine by means of hydrogen over palladium hydroxide catalyst. The resultant racemic amine intermediate is optically resolved with (R)-(2)-acetoxy-2-phenylacetic acid to yield the corresponding (R)- enantiomer, which is finally acylated with isobutyryl chloride to afford fesoterodine.

Synthetic route

isobutyryl chloride (79-30-1) + (R)-2-[3-(diisopropylamino)-1-phenylpropyl]-4-(hydroxymethyl)-phenol (207679-81-0) → fesoterodine (286930-02-7)

Conditions	Yield
With sodium hydroxide In water; toluene at 20℃; Product distribution / selectivity; Inert atmosphere;	98%
With sodium hydroxide In water; toluene at 20℃; for 0.166667h; Product distribution / selectivity; Inert atmosphere;	98%
With sodium hydroxide In water; toluene at 20℃; Inert atmosphere;	98%

(R)-2-(3-N,N-diisopropylamino-1-phenylpropyl)-4-trityloxymethylphenoxyisobutyrate (1539220-58-0) → fesoterodine (286930-02-7)

Conditions	Yield
With hydrogenchloride In water; acetonitrile at 50℃; for 1h; pH=2 - 2.5; Concentration; Time;	98%

fesoterodine fumarate → fesoterodine (286930-02-7)

Conditions	Yield
In dichloromethane; water at 20 - 30℃; Product distribution / selectivity;	92.6%

2-Methylpropionic anhydride (97-72-3) + (R)-2-[3-(diisopropylamino)-1-phenylpropyl]-4-(hydroxymethyl)-phenol (207679-81-0) → fesoterodine (286930-02-7)

Conditions	Yield
With potassium carbonate In tetrahydrofuran; ethanol at 0 - 20℃; Inert atmosphere;	83.8%

(R)-3-(N,N'-diisopropylamino-1-phenyl-propyl)-4-isobutyryloxy-benzoic acid (1391913-28-2) → fesoterodine (286930-02-7)

Conditions	Yield
With dimethylsulfide borane complex In tetrahydrofuran at 10 - 25℃;	60.5%

isobutyryl chloride (79-30-1) + (R)-2-[3-(diisopropylamino)-1-phenylpropyl]-4-(hydroxymethyl)-phenol (207679-81-0) → fesoterodine (286930-02-7) + C30H43NO4 (1208313-13-6)

Conditions	Yield
With N-ethyl-N,N-diisopropylamine In dichloromethane at -10 - -5℃; for 2.5h; Product distribution / selectivity;
With triethylamine In dichloromethane at -10 - -5℃; for 2.5h; Product distribution / selectivity;
Stage #1: isobutyryl chloride; (R)-2-[3-(diisopropylamino)-1-phenylpropyl]-4-(hydroxymethyl)-phenol In dichloromethane at -10 - -5℃; for 2.5h; Stage #2: With sodium carbonate In dichloromethane; water Product distribution / selectivity;

2-[(1R)-3-[bis(1-methylethyl)amino]-1-phenylpropyl]-4-hydroxy-methylphenyl isobutyrate mandelate (1206695-46-6) → fesoterodine (286930-02-7)

Conditions	Yield
With sodium hydrogencarbonate In dichloromethane; water for 0.166667h;

N,N-diisopropyl-3-(2-hydroxy-5-methyloxycarbonylphenyl)-3-phenylpropanamine → fesoterodine (286930-02-7)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: ethanol / 20 - 60 °C / Inert atmosphere 2.1: sodium hydrogencarbonate / ethyl acetate / Inert atmosphere 2.2: 3.5 h / 20 °C 2.3: 0.5 h / -10 - 20 °C 3.1: sodium hydroxide / toluene; water / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 4 steps 1.1: ethanol / 60 °C / Inert atmosphere 2.1: sodium hydrogencarbonate / ethyl acetate / Inert atmosphere 3.1: lithium aluminium tetrahydride / tetrahydrofuran / 3.5 h / 20 °C 3.2: -10 °C 4.1: sodium hydroxide / toluene; water / 0.17 h / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 4 steps 1.1: ethanol / 60 °C / Inert atmosphere 2.1: sodium hydrogencarbonate / ethyl acetate; water / Inert atmosphere 3.1: sodium hydroxide / methanol / 0 - 35 °C / Inert atmosphere 3.2: 5 - 25 °C 3.3: 3 h 4.1: sodium hydroxide / toluene; water / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 3 steps 1.1: sodium bis(2-methoxyethoxy)aluminium dihydride / toluene / 0 - 30 °C / Inert atmosphere 2.1: D-Malic acid / isopropyl alcohol; di-isopropyl ether / 20 - 80 °C 2.2: pH 10 View Scheme

methyl 4-hydroxylbenzoate (99-76-3) → fesoterodine (286930-02-7)

Conditions	Yield
Multi-step reaction with 4 steps 1.1: methanesulfonic acid / 50 - 55 °C / Inert atmosphere 2.1: ethanol / 20 - 60 °C / Inert atmosphere 3.1: sodium hydrogencarbonate / ethyl acetate / Inert atmosphere 3.2: 3.5 h / 20 °C 3.3: 0.5 h / -10 - 20 °C 4.1: sodium hydroxide / toluene; water / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 5 steps 1.1: methanesulfonic acid / water / 50 - 55 °C / Inert atmosphere 2.1: ethanol / 60 °C / Inert atmosphere 3.1: sodium hydrogencarbonate / ethyl acetate / Inert atmosphere 4.1: lithium aluminium tetrahydride / tetrahydrofuran / 3.5 h / 20 °C 4.2: -10 °C 5.1: sodium hydroxide / toluene; water / 0.17 h / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 5 steps 1.1: methanesulfonic acid / 50 - 55 °C / Inert atmosphere 2.1: ethanol / 60 °C / Inert atmosphere 3.1: sodium hydrogencarbonate / ethyl acetate; water / Inert atmosphere 4.1: sodium hydroxide / methanol / 0 - 35 °C / Inert atmosphere 4.2: 5 - 25 °C 4.3: 3 h 5.1: sodium hydroxide / toluene; water / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 5 steps 1.1: 1-methyl-piperazine / toluene / 25 - 110 °C 1.2: 5 h / 60 - 65 °C 2.1: hydrogen / 5%-palladium/activated carbon / methanol / 25 - 50 °C / 10343.2 Torr / Autoclave 3.1: sodium bis(2-methoxyethoxy)aluminium dihydride / toluene / 0 - 30 °C / Inert atmosphere 4.1: D-Malic acid / isopropyl alcohol; di-isopropyl ether / 20 - 80 °C 4.2: pH 10 View Scheme

3-(N,N-diisopropylamino)-1-phenylpropan-1-ol (906532-26-1) → fesoterodine (286930-02-7)

Conditions	Yield
Multi-step reaction with 4 steps 1.1: methanesulfonic acid / 50 - 55 °C / Inert atmosphere 2.1: ethanol / 20 - 60 °C / Inert atmosphere 3.1: sodium hydrogencarbonate / ethyl acetate / Inert atmosphere 3.2: 3.5 h / 20 °C 3.3: 0.5 h / -10 - 20 °C 4.1: sodium hydroxide / toluene; water / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 5 steps 1.1: methanesulfonic acid / water / 50 - 55 °C / Inert atmosphere 2.1: ethanol / 60 °C / Inert atmosphere 3.1: sodium hydrogencarbonate / ethyl acetate / Inert atmosphere 4.1: lithium aluminium tetrahydride / tetrahydrofuran / 3.5 h / 20 °C 4.2: -10 °C 5.1: sodium hydroxide / toluene; water / 0.17 h / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 5 steps 1.1: methanesulfonic acid / 50 - 55 °C / Inert atmosphere 2.1: ethanol / 60 °C / Inert atmosphere 3.1: sodium hydrogencarbonate / ethyl acetate; water / Inert atmosphere 4.1: sodium hydroxide / methanol / 0 - 35 °C / Inert atmosphere 4.2: 5 - 25 °C 4.3: 3 h 5.1: sodium hydroxide / toluene; water / 20 °C / Inert atmosphere View Scheme

(R)-(-)-3-(3-diisopropylamino-1-phenylpropyl)-4-hydroxybenzoic acid methyl ester → fesoterodine (286930-02-7)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: lithium aluminium tetrahydride / tetrahydrofuran / 3.5 h / 20 °C 1.2: -10 °C 2.1: sodium hydroxide / toluene; water / 0.17 h / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 2 steps 1.1: sodium hydroxide / methanol / 0 - 35 °C / Inert atmosphere 1.2: 5 - 25 °C 1.3: 3 h 2.1: sodium hydroxide / toluene; water / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 2 steps 1: sodium bis(2-methoxyethoxy)aluminium dihydride / tetrahydrofuran / 2 h / 0 - 5 °C / Inert atmosphere 2: sodium hydrogencarbonate / dichloromethane; water / 0.5 h / 0 - 5 °C / Inert atmosphere View Scheme

methyl (R)-(-)-3-(3-diisopropylamino-1-phenyl-propyl)-4-hydroxy-benzoate 2,3-dibenzoyl-D-tartaric acid salt (1294517-15-9) → fesoterodine (286930-02-7)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: sodium hydrogencarbonate / ethyl acetate / Inert atmosphere 2.1: lithium aluminium tetrahydride / tetrahydrofuran / 3.5 h / 20 °C 2.2: -10 °C 3.1: sodium hydroxide / toluene; water / 0.17 h / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 3 steps 1.1: sodium hydrogencarbonate / ethyl acetate; water / Inert atmosphere 2.1: sodium hydroxide / methanol / 0 - 35 °C / Inert atmosphere 2.2: 5 - 25 °C 2.3: 3 h 3.1: sodium hydroxide / toluene; water / 20 °C / Inert atmosphere View Scheme

(E)-3-phenylacrylic acid (140-10-3) → fesoterodine (286930-02-7)

Conditions	Yield
Multi-step reaction with 12 steps 1.1: sulfuric acid / 120 - 125 °C 2.1: potassium carbonate; sodium iodide / acetone / Reflux 3.1: sodium tetrahydroborate / 1,2-dimethoxyethane / 0.17 h 3.2: 3 h / 10 °C 4.1: triethylamine / dichloromethane / 12 h / 25 - 30 °C 5.1: acetonitrile / 30 h / 95 - 100 °C / autoclave; Sealed tube 6.1: isopropyl alcohol / 15 h / 25 - 86 °C 7.1: sodium hydroxide / water 8.1: ethyl bromide; iodine; magnesium / tetrahydrofuran / 1 h / 55 °C / Reflux 8.2: 1 h / -65 - -60 °C 9.1: thionyl chloride / 10 °C / Reflux 10.1: lithium aluminium tetrahydride / tetrahydrofuran / 14 h / 25 - 30 °C 11.1: hydrogen / 5% Pd(II)/C(eggshell) / methanol / 50 - 55 °C 12.1: dichloromethane / 1.5 h / 0 - 5 °C 12.2: 1 h / 0 - 5 °C View Scheme
Multi-step reaction with 10 steps 1.1: sulfuric acid / 120 - 125 °C / Inert atmosphere 2.1: potassium carbonate / acetone / Reflux 3.1: potassium hydroxide; water / methanol / Inert atmosphere; Reflux 3.2: pH 1 - 2 4.1: toluene / 0 - 10 °C 4.2: 50 - 60 °C 5.1: sodium tetrahydroborate; boron trifluoride diethyl etherate / tetrahydrofuran / 31 - 35 °C 5.2: 30 - 65 °C 6.1: isopropyl alcohol; water / Reflux 7.1: sodium carbonate / dichloromethane; water 7.2: 14 - 20 °C 8.1: hydrogenchloride; sodium tetrahydroborate / water / 32 - 38 °C 8.2: Reflux 9.1: sodium hydroxide; sodium carbonate / dichloromethane; water 9.2: Raney nickel 10.1: triethylamine / dichloromethane / 0.75 h / 0 - 20 °C View Scheme

methyl 4-(benzyloxy)-3-[(1R)-3-(dipropan-2-ylamino)-1-phenylpropyl]benzoate (156755-35-0) → fesoterodine (286930-02-7)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: lithium aluminium tetrahydride / tetrahydrofuran / 14 h / 25 - 30 °C 2.1: hydrogen / 5% Pd(II)/C(eggshell) / methanol / 50 - 55 °C 3.1: dichloromethane / 1.5 h / 0 - 5 °C 3.2: 1 h / 0 - 5 °C View Scheme
Multi-step reaction with 3 steps 1: sodium bis(2-methoxyethoxy)aluminium dihydride / toluene / 3 h / Inert atmosphere 2: hydrogen / Raney nickel / methanol / 20 °C 3: triethylamine / acetonitrile / -10 °C View Scheme
Multi-step reaction with 3 steps 1.1: sodium bis(2-methoxyethoxy)aluminium dihydride / toluene / 5 h / 0 - 20 °C / Inert atmosphere 1.2: 0 - 5 °C 2.1: hydrogen / 5%-palladium/activated carbon / methanol / 2 h / 25 - 35 °C / Autoclave 2.2: 25 - 35 °C 3.1: dichloromethane / 1.5 h / 0 - 5 °C 3.2: 0.5 h / 0 - 5 °C View Scheme

R-(-)-[3-(2-benzyloxy-5-bromophenyl)-3-phenylpropyl]diisopropylamine (950773-38-3) → fesoterodine (286930-02-7)

Conditions	Yield
Multi-step reaction with 5 steps 1.1: ethyl bromide; iodine; magnesium / tetrahydrofuran / 1 h / 55 °C / Reflux 1.2: 1 h / -65 - -60 °C 2.1: thionyl chloride / 10 °C / Reflux 3.1: lithium aluminium tetrahydride / tetrahydrofuran / 14 h / 25 - 30 °C 4.1: hydrogen / 5% Pd(II)/C(eggshell) / methanol / 50 - 55 °C 5.1: dichloromethane / 1.5 h / 0 - 5 °C 5.2: 1 h / 0 - 5 °C View Scheme
Multi-step reaction with 4 steps 1.1: magnesium / iodine / tetrahydrofuran / 1 h / -70 - 70 °C 1.2: -5 - 35 °C 1.3: pH 1 - 2 2.1: sodium bis(2-methoxyethoxy)aluminium dihydride / toluene / 0.25 h / 0 - 5 °C 3.1: hydrogen / 5%-palladium/activated carbon / methanol / 2 h / 25 - 35 °C / Autoclave 3.2: 25 - 35 °C 4.1: dichloromethane / 1.5 h / 0 - 5 °C 4.2: 0.5 h / 0 - 5 °C View Scheme
Multi-step reaction with 5 steps 1.1: iodine; magnesium; ethyl bromide / tetrahydrofuran / 2 h / 60 - 65 °C / Inert atmosphere 1.2: 1 h / -70 - -50 °C 2.1: thionyl chloride / 0 - 65 °C 3.1: lithium aluminium tetrahydride / tetrahydrofuran / 30 °C 4.1: hydrogen; palladium 10% on activated carbon / isopropyl alcohol / 25 - 30 °C / 2068.65 - 2585.81 Torr / Autoclave 5.1: sodium hydrogencarbonate / dichloromethane / 3 h / -2 - 3 °C View Scheme

Conditions	Yield
Multi-step reaction with 9 steps 1.1: triethylamine / dichloromethane / 12 h / 25 - 30 °C 2.1: acetonitrile / 30 h / 95 - 100 °C / autoclave; Sealed tube 3.1: isopropyl alcohol / 15 h / 25 - 86 °C 4.1: sodium hydroxide / water 5.1: ethyl bromide; iodine; magnesium / tetrahydrofuran / 1 h / 55 °C / Reflux 5.2: 1 h / -65 - -60 °C 6.1: thionyl chloride / 10 °C / Reflux 7.1: lithium aluminium tetrahydride / tetrahydrofuran / 14 h / 25 - 30 °C 8.1: hydrogen / 5% Pd(II)/C(eggshell) / methanol / 50 - 55 °C 9.1: dichloromethane / 1.5 h / 0 - 5 °C 9.2: 1 h / 0 - 5 °C View Scheme
Multi-step reaction with 8 steps 1.1: pyridine / dichloromethane / 5 - 30 °C / Industry scale 2.1: water / 75 - 78 °C / Industry scale 3.1: ethyl bromide; iodine; magnesium / tetrahydrofuran / 50 - 60 °C 3.2: -70 - -60 °C 3.3: -50 °C 4.1: borane-dimethyl sulfide complex / tetrahydrofuran / 25 - 50 °C 4.2: 0.5 h / 10 - 15 °C / Industry scale 5.1: raney nickel / methanol / 30 - 35 °C / Autoclave 6.1: tetrahydrofuran / 10 - 55 °C 7.1: potassium carbonate / toluene; water / 50 - 55 °C 8.1: dichloromethane / -25 - -20 °C View Scheme
Multi-step reaction with 8 steps 1.1: pyridine / dichloromethane / 5 - 30 °C / Industry scale 1.2: 5 - 30 °C / Industry scale 2.1: water / 75 - 78 °C / Industry scale 3.1: ethyl bromide; magnesium / iodine / tetrahydrofuran / 50 - 60 °C 3.2: -70 - -60 °C 4.1: dimethylsulfide borane complex / tetrahydrofuran / 25 - 50 °C 5.1: methanol / 30 - 35 °C 6.1: tetrahydrofuran / 10 - 55 °C 7.1: potassium carbonate / toluene; water / 50 - 55 °C 8.1: dichloromethane / -25 - -20 °C View Scheme

Upstream product

• 79-30-1 isobutyryl chloride 
• 207679-81-0 (R)-2-[3-(diisopropylamino)-1-phenylpropyl]-4-(hydroxymethyl)-phenol 
• 1206695-46-6 2-[(1R)-3-[bis(1-methylethyl)amino]-1-phenylpropyl]-4-hydroxy-methylphenyl isobutyrate mandelate 
• 140-10-3 (E)-3-phenylacrylic acid 
• 156755-35-0 methyl 4-(benzyloxy)-3-[(1R)-3-(dipropan-2-ylamino)-1-phenylpropyl]benzoate 
• 950773-38-3 R-(-)-[3-(2-benzyloxy-5-bromophenyl)-3-phenylpropyl]diisopropylamine 
• 106-41-2 4-bromo-phenol 
• 156755-23-6 6-bromo-4-phenyl-3,4-dihydro-2H-chromen-2-one 
• 156755-37-2 {4-(benzyloxy)-3-[(1R)-3-(dipropan-2-ylamino)-1-phenylpropyl]phenyl}methanol 
• 156755-24-7 methyl 3-[2-(benzyloxy)-5-bromophenyl]-3-phenylpropanoate 
• 250214-37-0 (+/-)-toluene-4-sulphonic acid 3-(2-benzyloxy-5-bromophenyl)-3-phenylpropyl ester 
• 156755-33-8 (R)-4-(benzyloxy)-3-(3-(diisopropylamino)-1-phenylpropyl)benzoic acid hydrochloride 
• 1135493-18-3 C₂₀H₁₈O₈*C₂₈H₃₄BrNO 
• 144-55-8 sodium hydrogencarbonate 

Downstream Products

• 286930-03-8 fesoterodine fumarate 
• 286930-03-8 fesoterodine fumarate 
• 1390644-34-4 isobutyric acid 2-((R)-3-diisopropylammonium-1-phenyIpropyl)-4-(hydroxymethyl)phenyl ester (R)-acetoxy(phenyl)acetate 
• 286930-03-8 2-[(1R)-3-(dipropan-2-ylamino)-1-phenylpropyl]-4-(hydroxymethyl)phenyl 2-methylpropanoate fumarate 

Relevant academic research and scientific papers

PROCESS FOR THE PREPARATION OF OPTICALLY PURE FESOTERODINE DERIVATIVES

3,3-diphenylpropylamines of general formula (I), particularly Fesoterodine, as well as their enantiomers, solvates and salts, can be produced by treating a compound of formula (II) with a chiral alcohol to yield the diastereomeric esters of formula (IV) and (IV′), which can be further transformed into a compound of formula (I), or an enantiomer, solvate or salt thereof, wherein R1 is C1-C8 alkyl; and R2 and R3, independently of one another, represent H or C1-C6 alkyl, or together form a ring of 3 to 7 members with the nitrogen to which they are bound.

PROCESS FOR THE PREPARATION OF 2-(3-N,N-DIISOPROPYLAMINO-1-PHENYLPROPYL)-4-HYDROXYMETHYL-PHENOL AND ITS DERIVATIVES

The invention concerns a process for the preparation of 2-(3-N,N- diisopropylamino-l-phenylpropyl)-4-hydroxymethyl-phenol and its derivatives, particularly the corresponding (R) 4-trityloxymethyl derivative, useful as intermediate form in the synthesis of Fesoterodine and its salts, in particular for the preparation of Fesoterodine fumarate salt.

PROCESS FOR THE PREPARATION OF FESOTERODINE OR ITS SALTS

The present invention relates to a process for the preparation of fesoterodine or its salts.

PROCESS FOR THE PREPARATION OF OPTICALLY ACTIVE 3,3-DIPHENYLPROPYLAMINES

The invention relates to a process for obtaining 3,3-diphenylpropylamines of general formula (I), particularly Fesoterodine, as well as their enantiomers, solvates and salts, comprising treating a compound of formula (II) with a chiral alcohol to yield the diastereomeric esters of formula (IV) and (IV'), which can be further transformed into a compound of formula (I), or an enantiomer, solvate or salt thereof, wherein R1 is C1-C8 alkyl; and R2 and R3, independently of one another, represent H or C1-C6 alkyl, or together form a ring of 3 to 7 members with the nitrogen to which they are bound.

PROCESS FOR THE PREPARATION OF MUSCARINIC RECEPTOR ANTAGONIST

The present invention relates to novel and improved processes for the preparation of (r)-2-(3-(diisopropylamino)-1-phenylpropyl)-4-(hydroxymethyl)phenylisobutyrate represented by the following structural formula-1 and its pharmaceutically acceptable salts thereof.

PROCESSES FOR THE PREPARATION OF FESOTERODINE

The invention relates to improved process for the preparation of fesoterodine and its pharmaceutically acceptable salt, specifically fesoterodine fumarate of formula (1). The invention relates to solid state forms of a novel salt of fesoterodine and process for the preparation thereof. The invention also relates to highly pure fesoterodine fumarate substantially free of impurity X at RRT 1.37. The invention also provides solid particles of pure fesoterodine fumarate wherein 90 volume-percent of the particles (D90) have a size of higher than 200 microns.

A PROCESS FOR PREPARING FESOTERODINE

The present invention relates to an improved process for the preparation of Fesoterodine and pharmaceutically acceptable salts thereof. The present invention particularly relates to a process for the preparation of fesoterodine and pharmaceutically acceptable salts thereof which involves use and preparation of R(+) benzyl tolterodine and fumarate salt of R(+)-[4-benzyloxy-3-(3-diisopropylamino-1-phenylpropyl)-phenyl]-methanol.

"Process for the preparation of fesoterodine or a salt thereof"

A process for the preparation of (R)-2-(3-diisopropylamino-1-phenylpropyl)-4-(hydroxymethyl)-phenol isobutyrate (Fesoterodine) or a pharmaceutically acceptable salt thereof having low content in impurities.

PROCESS FOR THE PREPARATION OF FESOTERODINE OR A SALT THEREOF

A process for the preparation of (R)-2-(3-diisopropylamino-1-phenylpropyl)-4-(hydroxymethyl)-phenol isobutyrate (Fesoterodine) or a pharmaceutically acceptable salt thereof having low content in impurities.

Fesoterodine Substantially Free of Dehydroxy Impurity

Provided herein is an impurity of fesoterodine, fesoterodine dehydroxy impurity, 2-[(1R)-3-[bis(1-methylethy)amino]-1-phenylpropyl]-4-methylphenyl isobutyrate, and a process for preparing and isolating thereof. Provided further herein is a highly pure fesoterodine or a pharmaceutically acceptable salt thereof substantially free of fesoterodine dehydroxy impurity, process for the preparation thereof, and pharmaceutical compositions comprising highly pure fesoterodine or a pharmaceutically acceptable salt thereof substantially free of dehydroxy impurity. Provided also herein is a pharmaceutical composition comprising solid particles of pure fesoterodine fumarate substantially free of dehydroxy impurity, wherein 90 volume-percent of the particles (D90) have a size of less than about 200 microns.