276863-95-7

Usage

Uses

Used in Pharmaceutical Industry:
3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile is used as a reactant for the preparation of dual 5-HT1A receptor agonists and serotonin reuptake inhibitors. Its chemical structure allows it to interact with the serotonin system, which plays a crucial role in various physiological processes and is often targeted in the treatment of mood disorders, anxiety, and other conditions.
As a reactant in the synthesis of these dual-action compounds, 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile contributes to the development of medications that can potentially provide more effective treatment options for patients suffering from serotonin-related disorders. The compound's ability to modulate the serotonin system through both agonist and reuptake inhibitor actions makes it a valuable asset in the pharmaceutical industry's ongoing efforts to create more effective and targeted therapies.

Synthetic route

1H-indole-5-carbonitrile (15861-24-2) + 4-Chlorobutanoyl chloride (4635-59-0) → 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7)

Conditions	Yield
With aluminum (III) chloride In dichloromethane at 0 - 20℃;	93%
With titanium tetrachloride In chloroform at 0℃; for 20h; Solvent; Temperature;	90%
Stage #1: 4-Chlorobutanoyl chloride With aluminum (III) chloride In 1,2-dichloro-ethane at 0℃; for 1h; Stage #2: 1H-indole-5-carbonitrile In 1,2-dichloro-ethane at 0 - 20℃; for 2.5h;	87.4%

1H-indole-5-carbonitrile (15861-24-2) + 4-Chlorobutanoyl chloride (4635-59-0) → C13H11ClN2O + 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7)

Conditions	Yield
With isobutylaluminum dichloride In dichloromethane Friedel-Crafts Acylation;

SD-169 (1670-87-7) → 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: aluminum (III) chloride / dichloromethane / 1 h / 5 °C / Cooling with ice; Large scale 1.2: 20 °C / Cooling with ice; Large scale 2.1: trichlorophosphate / dichloromethane / 10 °C / Cooling with ice; Large scale View Scheme

5-aminocarbonyl-3-(4-chlorobutyryl)indole → 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7)

Conditions	Yield
With trichlorophosphate In dichloromethane at 10℃; Cooling with ice; Large scale;	51 kg

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-(4-chlorobutyl)-5-cyanoindole (143612-79-7)

Conditions	Yield
With chloro-trimethyl-silane; sodium cyanoborohydride In acetonitrile at 0 - 30℃;	87.2%
Stage #1: 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile With aluminum (III) chloride In tetrahydrofuran for 0.5h; Cooling with ice; Stage #2: With sodium tetrahydroborate In tetrahydrofuran Reagent/catalyst;	80%
With iron(III) chloride; borane-THF; hydrogen In tetrahydrofuran at 20℃; Reagent/catalyst; Temperature; Inert atmosphere; Flow reactor;	71%

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) + 5-(1-piperazinyl)benzofuran-2-carboxamide (183288-46-2) → vilazodone N-oxide

Conditions	Yield
With triethylamine; potassium iodide In N,N-dimethyl-formamide at 20 - 90℃; for 49h; Inert atmosphere;	85%
With tributyl-amine In 1-methyl-pyrrolidin-2-one at 25 - 130℃; for 24h;	7%

2-Naphthalenesulfonyl chloride (93-11-8) + 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-(4-chlorobutyryl)-1-(naphthalen-2-yl-sulfonyl)-1H-indole-5-carbonitrile

Conditions	Yield
Stage #1: 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile With sodium hydride In N,N-dimethyl-formamide at 0 - 20℃; for 0.5h; Stage #2: 2-Naphthalenesulfonyl chloride In N,N-dimethyl-formamide at 0 - 20℃; for 16h;	82%

p-toluenesulfonyl chloride (98-59-9) + 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 1-p-toluenesulfonyl-3-(4-chlorobutyryl)-5-cyanoindole (1398358-62-7)

Conditions	Yield
With sodium hydroxide In dichloromethane at 20℃; for 5h;	81%

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-(4-hydroxybutanoyl)-1H-indole-5-carbonitrile

Conditions	Yield
With triethylamine In water; acetonitrile at 80 - 85℃; for 5h;	81%

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-(4-hydroxybutyl)-1H-indole-5-carbonitrile (914927-40-5)

Conditions	Yield
With sodium tetrahydroborate; isopropyl alcohol at 0 - 80℃; for 6h;	80%
With sodium tetrahydroborate In isopropyl alcohol at 80℃; for 6h;	80.6%
With sodium tetrahydroborate In isopropyl alcohol at 0 - 80℃; for 6h;	80%
With sodium tetrahydroborate; isopropyl alcohol at 0 - 80℃; for 6h; Inert atmosphere;	80%
With sodium tetrahydroborate; isopropyl alcohol at 0 - 80℃; for 6h;	80%

1-Naphthalenesulfonyl chloride (85-46-1) + 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-(4-chlorobutyryl)-1-(naphthalen-1-yl-sulfonyl)-1H-indole-5-carbonitrile

Conditions	Yield
Stage #1: 3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile With sodium hydride In N,N-dimethyl-formamide at 0 - 20℃; for 0.5h; Stage #2: 1-Naphthalenesulfonyl chloride In N,N-dimethyl-formamide at 0 - 20℃;	76%

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-(4-chloro-1-hydroxy-butyl)-1H-indol-5-carbonitrile (1451194-34-5)

Conditions	Yield
With sodium tetrahydroborate; water; sodium hydroxide In tetrahydrofuran at 30 - 35℃; for 3h;	73.5%
With sodium tetrahydroborate; water; sodium hydroxide In tetrahydrofuran at 30 - 35℃; for 3h;	73.5%

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-{4-[4-(4-cyano-phenyl)-piperazin-1-yl]-butyl}-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-[4-(4-benzo[1,3]dioxol-5-yl-piperazin-1-yl)-butyl]-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: 60 percent / K2CO3; KI / dimethylformamide / 12 h / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-{4-[4-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-piperazin-1-yl]-butyl}-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-(4-(4-(2-oxo-2H-1-benzopyran-6-yl)piperazin-1-yl)butyl)indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-{4-[4-(2-cyano-benzofuran-5-yl)-piperazin-1-yl]-butyl}-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → vilazodone (163521-12-8)

Conditions	Yield
Multi-step reaction with 4 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; Et3N / acetonitrile / 12 h / Heating 3: KOH / methanol / 3 h / Heating 4: 72 percent / 1-methyl-2-chloropyridinium iodide; Et2NiPr; NH3(g) / 1-methyl-pyrrolidin-2-one View Scheme
Multi-step reaction with 3 steps 1: sodium bis(2-methoxyethoxy)aluminium dihydride / tetrahydrofuran 2: potassium carbonate / acetonitrile 3: potassium hydroxide / methanol View Scheme
Multi-step reaction with 4 steps 1.1: sodium bis(2-methoxyethoxy)aluminium dihydride / tetrahydrofuran 2.1: potassium carbonate / acetonitrile 3.1: potassium hydroxide / methanol 4.1: 1,1'-carbonyldiimidazole / methanol / 1 h / 20 °C / Reflux; Large scale 4.2: 0.5 h / Large scale View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-[4-(4-phenyl-piperazin-1-yl)-butyl]-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-{4-[4-(2-methoxy-phenyl)-piperazin-1-yl]-butyl}-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-[4-(4-p-methoxyphenylpiperazino)butyl]-5-cyanoindole (143612-66-2)

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-{4-[4-(4-fluoro-phenyl)-piperazin-1-yl]-butyl}-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-[4-(4-p-hydroxyphenylpiperazino)butyl]-5-cyanoindole

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-[4-(4-benzofuran-5-yl-piperazin-1-yl)-butyl]-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-[4-(4-benzo[1,2,5]thiadiazol-4-yl-piperazin-1-yl)-butyl]-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-{4-[4-(5-chloro-2-methoxy-phenyl)-piperazin-1-yl]-butyl}-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-{4-[4-(3,4-dimethoxy-phenyl)-piperazin-1-yl]-butyl}-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-[4-(4-benzo[1,2,5]thiadiazol-5-yl-piperazin-1-yl)-butyl]-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-{4-[4-(1H-indol-5-yl)-piperazin-1-yl]-butyl}-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-{4-[4-(4-cyano-3-methoxy-phenyl)-piperazin-1-yl]-butyl}-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 3-{4-[4-(2,3-dihydro-benzofuran-5-yl)-piperazin-1-yl]-butyl}-1H-indole-5-carbonitrile

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 2-{4-[4-(5-cyano-1H-indol-3-yl)-butyl]-piperazin-1-yl}-benzamide

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

3-(4-chlorobutanoyl)-1H-indole-5-carbonitrile (276863-95-7) → 4-{4-[4-(5-cyano-1H-indol-3-yl)-butyl]-piperazin-1-yl}-benzamide

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / sodium bis(2-methoxyethoxy)aluminum hydride / tetrahydrofuran; toluene / 2 h 2: K2CO3; KI / dimethylformamide / Heating View Scheme

Upstream product

• 15861-24-2 1H-indole-5-carbonitrile 
• 4635-59-0 4-Chlorobutanoyl chloride 
• 1670-87-7 SD-169 

Downstream Products

• 1398358-62-7 3-(4-chlorobutanoyl)-1-tosyl-1H-indole-5-carbonitrile 
• 914927-40-5 3-(4-hydroxybutyl)-1H-indole-5-carbonitrile 
• 1451194-34-5 3-(4-chloro-1-hydroxy-butyl)-1H-indol-5-carbonitrile 
• 816438-46-7 3-(4-chloro-butyl)-2,3-dihydro-1H-indole-5-carbonitrile 
• 163521-11-7 5-(4-[4-(5-cyano-3-indolyl)butyl]-1-piperazinyl)benzofuran-2-carboxylic acid ethyl ester 
• 163521-19-5 5-{4-[4-(5-cyano-1H-indol-3-yl)butyl]piperazin-1-yl}benzofuran-2-carboxylic acid 
• 143612-66-2 3-[4-(4-p-methoxyphenylpiperazino)butyl]-5-cyanoindole 

Relevant academic research and scientific papers

Design, synthesis and evaluation of vilazodone-tacrine hybrids as multitarget-directed ligands against depression with cognitive impairment

Depression, a severe mental disease, is greatly difficult to treat and easy to induce other neuropsychiatric symptoms, the most frequent one is cognitive impairment. In this study, a series of novel vilazodone-tacrine hybrids were designed, synthesized and evaluated as multitarget agents against depression with cognitive impairment. Most compounds exhibited good multitarget activities and appropriate blood-brain barrier permeability. Specifically, compounds 1d and 2a exhibited excellent 5-HT1A agonist activities (1d, EC50 = 0.36 ± 0.08 nM; 2a, EC50 = 0.58 ± 0.14 nM) and 5-HT reuptake inhibitory activities (1d, IC50 = 20.42 ± 6.60 nM; 2a, IC50 = 22.10 ± 5.80 nM). In addition, they showed moderate ChE inhibitory activities (1d, AChE IC50 = 1.72 ± 0.217 μM, BuChE IC50 = 0.34 ± 0.03 μM; 2a, AChE IC50 = 2.36 ± 0.34 μM, BuChE IC50 = 0.10 ± 0.01 μM). Good multitarget activities with goodt blood-brain barrier permeability of 1d and 2a make them good lead compounds for the further study of depression with cognitive impairment.

Substituted indole compound and method and use thereof

The invention provides a new indole compound, pharmaceutically acceptable salts and medicinal preparations thereof, and a use of the new indole compound in selective inhibition of 5-hydroxytryptamine reuptake and /or excitation of a 5-HT1A receptor. The invention also relates to medicinal compositions comprising the compounds, and a method for treating the central nervous system dysfunction of mammals, especially humans by using the medicinal compositions.

Substituted indole compounds, as well as using method and application thereof

The invention relates to substituted indole compounds, a using method and application of the substituted indole compounds, as well as a medicine composition including the compounds and application thereof. The compounds or medicine composition can be used for inhibiting reuptake of 5-hydroxytryptamine. The invention further relates to a method for preparing the compounds and the medicine composition, as well as application of the compounds and medicine composition in treatment of central nervous system dysfunction.

Preparation method of substituted indoles compounds

The invention belongs to the field of medical technology, and discloses a preparation method of 3-substituted indoles compounds. The preparation method includes using a compound represented by formula (2) as an initial raw material, performing a Friedel-Crafts reaction with 4-chlorobutyryl chloride in the presence of anhydrous titanium tetrachloride catalyst to obtain a compound represented by formula (3), and performing a reaction with paratoluensulfonyl chloride in the presence of an organic solvent and an acid-binding agent to obtain the target compound. The preparation method overcomes the defects of the synthetic method in the prior art, and is suitable for the industrial production. The product has high content, and the purity of the product reaches over 99%.

For the preparation of the compounds and intermediates thereof the vera assists the alkone and application

The invention belongs to the field of medicinal chemistry and relates to a compound for preparing vilazodone as well as an intermediate and an application thereof. The compound for preparing vilazodone is shown as a formula I, and the intermediate for synthesizing the compound of the formula I is shown as a formula II. The compound of the formula I can be applied to preparation of vilazodone and pharmaceutically acceptable salts thereof. The compound of the formula I serving as a novel intermediate is applied in preparation of the vilazodone, the defects in the conventional literature report are overcome, metal catalysts with high toxicity and organic phosphorus ligands thereof are avoided, the preparation cost is greatly reduced, the operation is simplified, and the compound is stable and controllable in quality and suitable for large-scale industrial preparation.

SUBSTITUTED PIPERAZINE COMPOUNDS AND METHODS OF USE AND USE THEREOF

The invention relates to substituted piperazine compounds and methods of use and uses thereof, and further to the pharmaceutical compositions comprising the compounds and uses thereof, wherein the compound has Formula (I) or a stereoisomer, a tautomer, an N-oxide, a solvate, a metabolite, a pharmaceutically acceptable salt or a prodrug thereof. The substituted piperazine compounds and pharmaceutical compositions comprising the compounds disclosed herein can be used for inhibiting 5-hydroxytryptamine reuptake and/or stimulating 5-HT1A receptors. The invention also relates to processes for preparing these compounds and pharmaceutical compositions, and their uses in the treatment of a central nervous system dysfunction.

Intermediate the vera assists the alkone 5-cyano -3 (4-chlorobutyl)-indole new synthetic process

The invention discloses a new synthetic process of a vilazodone intermediate 5-cyano-3(4-chlorobutyl)-indole. The synthetic process comprises the steps of enabling 5-amino-formyl-indole and 4-chlorobutyryl chloride undergo a 3-bit acylation reaction and a dehydration reaction of an amido bond in the presence of a catalyst to produce 5-bit cyan, then performing a decarbonylation reaction in the presence of a reducing agent to generate a product, and finally refining by the product by use of methanol to obtain high-purity high-content 5-cyano-3(4-chlorobutyl)-indole. The process is concise, simple to operate and applicable to large-scale industrial production.

SUBSTITUTED HETEROARYL COMPOUNDS AND METHODS OF USE THEREOF

Provided herein are novel heteroaryl compounds, pharmaceutically acceptable salts and pharmaceutical formulations thereof for selectively inhibiting serotonin reuptake and/or acting as 5-HT1A receptor agonists. Also provided herein are pharmaceutical compositions comprising the heteroaryl compounds and methods of using the pharmaceutical compositions in treating central nervous system (CNS) dysfunction in a mammal, especially a human being.

SUBSTITUTED PIPERAZINE COMPOUNDS AND METHODS AND USE THEREOF

Provided herein are novel piperazine compounds acting as selective serotonin reuptake inhibitors and/or the 5-HT1A receptor agonists. The invention also relates to the methods of preparing the compound and pharmaceutical composition, and the use of treating central nervous system dysfunction in mammals especially in humans.

PROCESS FOR THE PREPARATION OF VILAZODONE HYDROCHLORIDE AND ITS AMORPHOUS FORM

The present invention relates to an improved process for the preparation of vilazodone Hydrochloride and a process for preparation of novel pure amorphous form of vilazodone hydrochloride.