Nateglinide
C19H27NO3 317.42
d-Phenylalanine, N-[[trans-4-(1-methylethyl)cyclohexyl]carbonyl]-;
(
)-N-[(trans-4-Isopropylcyclohexyl)carbonyl-d-phenylalanine
[105816-04-4].
(na te glye' nide).
+'&img=../../images/v35300/cas-105816-04-4.gif&casNumber=105816-04-4&usp=35&nf=30&chemicalStructureImage=true&ID='+parent.myID,600,500);)
C19H27NO3 317.42
d-Phenylalanine, N-[[trans-4-(1-methylethyl)cyclohexyl]carbonyl]-;
(
)-N-[(trans-4-Isopropylcyclohexyl)carbonyl-d-phenylalanine
[105816-04-4].DEFINITION
Nateglinide contains NLT 98.0% and NMT 102.0% of C19H27NO3, calculated on the dried basis.
IDENTIFICATION
• B.
The retention time of the major peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.
ASSAY
• Procedure
Buffer:
8.5 g/L of anhydrous dibasic sodium phosphate in water. Adjust with phosphoric acid to a pH of 7.5.
Mobile phase:
Methanol and Buffer (1:1)
System suitability stock solution:
0.2 mg/mL each of USP Nateglinide Related Compound C RS and dl-phenylalanine in methanol. [Note—Sonicate, if necessary. ]
System suitability solution:
Transfer USP Nateglinide RS to a suitable volumetric flask, dissolve first in methanol, using 45% of the final volume, add System suitability stock solution equal to 5% of the final volume, and then dilute with Buffer to volume to obtain a solution containing about 1.0 mg/mL of nateglinide and about 0.01 mg/mL each of nateglinide related compound C and dl-phenylalanine.
Standard solution:
1.0 mg/mL of nateglinide prepared as follows: transfer USP Nateglinide RS to a suitable volumetric flask, dissolve first in methanol, using 50% of the final volume, and then dilute with Buffer to volume.
Sample solution:
Transfer about 100 mg of Nateglinide to a 100-mL volumetric flask, dissolve in 50 mL of methanol, and dilute with Buffer to volume.
Chromatographic system
Mode:
LC
Detector:
UV 210 nm
Column:
6-mm × 15-cm; 6-µm packing L71 (see Chromatographic Reagents under Reagents, Indicators, and Solutions)
Column temperature:
30
Flow rate:
1 mL/min
Injection size:
20 µL
System suitability
Samples:
System suitability solution and Standard solution
Suitability requirements
Resolution:
NLT 0.9 between nateglinide related compound C and nateglinide, System suitability solution
Relative standard deviation:
NMT 1.0%, Standard solution
Analysis
Samples:
Standard solution and Sample solution
Calculate the percentage of nateglinide (C19H27NO3) in the portion of Nateglinide taken:
Result = (rU/rS) × (CS/CU) × 100
| rU | = | = peak response from the Sample solution |
| rS | = | = peak response from the Standard solution |
| CS | = | = concentration of USP Nateglinide RS in the Standard solution (mg/mL) |
| CU | = | = concentration of Nateglinide in the Sample solution (mg/mL) |
Acceptance criteria:
98.0%–102.0% on the dried basis
IMPURITIES
• Residue on Ignition 
281
:
NMT 0.1%
281:
NMT 0.1%
• Heavy Metals, Method II 231:
NMT 10 ppm
231:
NMT 10 ppm
• Limit of Nateglinide Related Compound A and Other Impurities
Buffer:
7.8 g/L of monobasic sodium phosphate in water. Adjust with phosphoric acid to a pH of 2.5.
Mobile phase:
Acetonitrile and Buffer (7:13)
System suitability stock solution:
Dissolve USP Nateglinide Related Compound A RS in acetonitrile to obtain a solution containing about 0.6 mg/mL. Further dilute this solution with Mobile phase to obtain a solution containing about 0.12 mg/mL.
System suitability solution:
Transfer an amount of USP Nateglinide RS to a suitable volumetric flask, dissolve first in acetonitrile using 10% of the final volume, then add System suitability stock solution equal to 10% of the final volume, and dilute with Mobile phase to volume to obtain a solution containing about 6 mg/mL of nateglinide and about 0.012 mg/mL of nateglinide related compound A.
Standard solution:
Dissolve USP Nateglinide RS in acetonitrile to obtain a solution having a known concentration of about 0.3 mg/mL. Further dilute this solution with Mobile phase to obtain a solution having a known concentration of about 0.06 mg/mL.
Sample solution:
Transfer 60 mg of Nateglinide to a 10-mL volumetric flask, dissolve in a minimal amount of acetonitrile, and dilute with Mobile phase to volume.
Chromatographic system
Mode:
LC
Detector:
UV 210 nm
Column:
3.9-mm × 5-cm; 5-µm packing L7
Column temperature:
40
Flow rate:
2 mL/min
Injection size:
100 µL
Run time:
5 times the retention time of nateglinide
System suitability
Samples:
System suitability solution and Standard solution
Suitability requirements
Resolution:
NLT 2.5 between nateglinide related compound A and nateglinide, System suitability solution
Relative standard deviation:
NMT 2.0%, Standard solution
Analysis
Samples:
Standard solution and Sample solution
Calculate the percentage of each impurity in the portion of Nateglinide taken:
Result = (rU/rS) × (CS/CU) × (1/F) × 100
| rU | = | = peak response of each impurity from the Sample solution |
| rS | = | = peak response of nateglinide from the Standard solution |
| CS | = | = concentration of USP Nateglinide RS in the Standard solution (mg/mL) |
| CU | = | = concentration of Nateglinide in the Sample solution (mg/mL) |
| F | = | = relative response factor (see Table 1) |
Acceptance criteria
Individual impurities:
See Table 1.
Table 1
| Name | Relative Retention Time |
Relative Response Factor |
Acceptance Criteria, NMT (%) |
|---|---|---|---|
| Nateglinide related compound Aa | 0.5 | 0.015 | 0.2 |
| Ethyl analogb | 0.6 | 1.0 | 0.1 |
| Nateglinide | 1.0 | — | — |
| IPP impurityc | 3.1 | 1.0 | 0.1 |
| Ester impurityd | 4.1 | 0.94 | 0.1 |
| Any other individual impurity | — | 1.0 | 0.1 |
|
a
trans-4-Isopropylcyclohexylcarboxylic acid.
b
N-(trans-4-Ethylcyclohexylcarbonyl)-d-phenylalanine.
c
N-(trans-4-Isopropylcyclohexylcarbonyl)-d-phenylalanine-d-phenylalanine.
d
N-(trans-4-isopropylcyclohexylcarbonyl)-d-phenylalanine-ethyl ester.
|
|||
• Limit of Nateglinide Related Compound B
Mobile phase:
0.77 g/L of ammonium acetate in methanol.
[Note—The following solutions are stable for up to 48 h when stored in a refrigerator. ]
System suitability solution:
10 mg/mL of USP Nateglinide RS and 0.02 mg/mL of USP Nateglinide Related Compound B RS in methanol
Standard solution:
0.02 mg/mL of USP Nateglinide Related Compound B RS in methanol. [Note—Nateglinide related compound B is N-(trans-4-isopropyl-cyclohexylcarbonyl)-l-phenylalanine. ]
Sample solution:
10 mg/mL of Nateglinide in methanol
Chromatographic system
Mode:
LC
Detector:
UV 220 nm
Column:
4-mm × 25-cm or 4.6-mm × 25-cm; 5-µm packing L72 (see Chromatographic Reagents under Reagents, Indicators, and Solutions)
Column temperature:
40
Flow rate:
0.8 mL/min. [Note—The flow rate can be adjusted as needed to achieve a recommended retention time of nateglinide related compound B at about 25 min. ]
Injection size:
10 µL
System suitability
[Note—The elution order is nateglinide related compound B, followed by the nateglinide peak. ]
Samples:
System suitability solution and Standard solution
Suitability requirements
Resolution:
NLT 0.8 between nateglinide related compound B and nateglinide, System suitability solution
Relative standard deviation:
NMT 5%, Standard solution
Analysis
Samples:
Standard solution and Sample solution
Calculate the percentage of nateglinide related compound B in the portion of Nateglinide taken:
Result = (rU/rS) × (CS/CU) × 100
| rU | = | = peak response of nateglinide related compound B from the Sample solution |
| rS | = | = peak response of nateglinide related compound B from the Standard solution |
| CS | = | = concentration of USP Nateglinide Related Compound B RS in the Standard solution (mg/mL) |
| CU | = | = concentration of Nateglinide in the Sample solution (mg/mL) |
Acceptance criteria:
NMT 0.2%
• Limit of Nateglinide Related Compound C and Phenylalanine
Mobile phase, System suitability solution, Standard solution, Sample solution, and Chromatographic system:
Proceed as directed in the Assay.
Diluted standard solution:
Dilute the Standard solution with Mobile phase to obtain a solution having a known concentration of about 0.01 mg/mL of nateglinide.
Analysis
Samples:
Sample solution and Diluted standard solution
Calculate the percentage of each specified impurity listed in Table 2 in the portion of Nateglinide taken:
Result = (rU/rS) × (CS/CU) × (1/F) × 100
| rU | = | = peak response of each impurity from the Sample solution |
| rS | = | = peak response of nateglinide from the Diluted standard solution |
| CS | = | = concentration of nateglinide in the Diluted standard solution (mg/mL) |
| CU | = | = concentration of Nateglinide in the Sample solution (mg/mL) |
| F | = | = relative response factor of each individual impurity (see Table 2) |
Acceptance criteria
Individual impurities:
See Table 2.
Table 2
| Name | Relative Retention Time |
Relative Response Factor |
Acceptance Criteria, NMT (%) |
|---|---|---|---|
| Phenylalanine | 0.2 | 1.5 | 0.2 |
| Nateglinide cis-isomera (related compound C) | 0.9 | 0.97 | 0.2 |
| Nateglinide | 1.0 | — | — |
|
a
N-(cis-4-isopropylcyclohexylcarbonyl)-d-phenylalanine.
|
|||
Total impurities:
The sum of all impurities found in the tests for Limit of Nateglinide Related Compound A and Other Impurities, Limit of Nateglinide Related Compound B, and Limit of Nateglinide Related Compound C and Phenylalanine is NMT 0.5%.
SPECIFIC TESTS
• Loss on Drying 731:
Dry a sample at 105 for 2 h: it loses NMT 0.5% of its weight.
731:
Dry a sample at 105 for 2 h: it loses NMT 0.5% of its weight.
ADDITIONAL REQUIREMENTS
• Packaging and Storage:
Preserve in tight containers. Store at room temperature.
• USP Reference Standards 11
11
USP Nateglinide RS 
()-N-[(trans-4-Isopropylcyclohexyl)carbonyl-d-phenylalanine.
C19H27NO3 317.42
') + '&img=../../images/v35300/cas-105816-04-4.gif',600,500);)
(
)-N-[(trans-4-Isopropylcyclohexyl)carbonyl-d-phenylalanine.
C19H27NO3 317.42
USP Nateglinide Related Compound A RS
trans-4-Isopropylcyclohexylcarboxylic acid.
C10H18O2 170.2
trans-4-Isopropylcyclohexylcarboxylic acid.
C10H18O2 170.2
USP Nateglinide Related Compound B RS
N-(trans-4-Isopropylcyclohexylcarbonyl)-l-phenylalanine.
C19H27NO3 317.4
N-(trans-4-Isopropylcyclohexylcarbonyl)-l-phenylalanine.
C19H27NO3 317.4
USP Nateglinide Related Compound C RS
Nateglinide cis-isomer, N-(cis-4-isopropylcyclohexylcarbonyl)-d-phenylalanine.
C19H27NO3 317.4
Nateglinide cis-isomer, N-(cis-4-isopropylcyclohexylcarbonyl)-d-phenylalanine.
C19H27NO3 317.4
Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
| Topic/Question | Contact | Expert Committee |
|---|---|---|
| Monograph | Elena Gonikberg, Ph.D.
Principal Scientific Liaison 1-301-816-8251 |
(SM32010) Monographs - Small Molecules 3 |
| Reference Standards | RS Technical Services 1-301-816-8129 rstech@usp.org |
USP35–NF30 Page 4004
Pharmacopeial Forum: Volume No. 34(6) Page 1463