L-Leucine Methyl Ester Hydrochloride CAS 7517-19-3 (H-Leu-OMe·HCl) Assay >99.0% Factory

1. Appearance
Take an appropriate amount of this product, put it on smooth white paper and spread 5 cm2 and 5 mm thick. Observe it in a bright place.
2. Purity (HPLC)
2.1 Instrument
High performance liquid chromatography, PDA detector.
Electronic analytical balance
2.2 Reagents
Acetonitrile (chromatographic grade), TFA(chromatographic grade)
2.3 Chromatographic conditions
2.3.1 Column: YMC-ODS-AM, 5 μl, 150 x 4.6 mm
2.3.2
Detection wavelength: INC220nm
Flow rate: 1.0mL/min
Injection volume:10 μL (for reference)
Diluent: Acetonitrile
Run time: 20 minutes
2.4 Mobile phase preparation
Mobile phase A (0.1% trifluoroacetic acid water): accurately absorbing 2.0ml TFA, Dilute to 2000ml with water, mix and degas;
Mobile phase B (0.1% trifluoroacetic acid acetonitrile ): accurately absorbing 2.0ml TFA, Dilute to 2000ml with acetonitrile, mix and degas;
2.5 Instrumental parameters
Time (min) A% B%
0.00 90 10
12.00 10 90
15.00 10 90
15.01 90 10
20.00 90 10
2.6 Preparation of sample solution
Weigh and dissolve 0.1g sample with acetonitrile, dilute to 100ml, shake well for use, or the same concentration. Prepare two samples in parallel.
2.7 Sample Determination
Analyze the sample according to the following sampling procedure:
More than 1 injection of blank solution
1 needle sample solution 1#
1 needle sample solution 2#
2.8 Result Calculation
2.8.1 The peak area normalization method was used to calculate the HPLC purity by deducting blank space.
2.8.2 The relative mean deviation of the purity of two needles shall not be greater than 1%
2.8.3 If the results of both injections meet the acceptance criteria, the average purity is taken as the final result.
3, Melting point -- RY-1 melting point instrument
4. Loss on drying test method
4.1 Instruments:
Electric thermostatic drying oven, 1/10,000 balance.
4.2 Procedure:
In a flat weighing bottle with a constant weight and over-drying ground mouth cover, weigh 1 gram (accurate to 0.0001 gram) of the sample. The sample should be evenly spread at the bottom of the weighing bottle with a thickness of no more than 10mm, put in a thermostatic electric drying oven, dry at 105~110℃ for 3 hours, and then move into the drying room to cool to room temperature for weighing.
Calculation: Loss on drying %= (M1-M2) ÷M×100
Where: M1: weight of sample and measuring bottle before drying, grams
M2: weight of sample and measuring bottle after drying, in grams
M: Sample weight, grams
5. Specific rotation
-- Specific rotation is measured in accordance with GB/T613-1988
Sample preparation: 1.0000g sample was accurately weighed and moved to a clean and dry 50ml volumetric bottle, 20ml water was added, the bottle was capped and shaken to dissolve, and then diluted to the scale with water.
Test: Adjust the zero of the gyroscope before the test, then load the test tube with the sample solution, record the rotation Angle, and calculate the specific rotation of the sample with the following formula.
[а]D20 = (r×50) ÷ (L×W)
[а]D20: Specific optical rotation at 20℃ of sample solution
r: Optical rotation observed at 20℃ for the sample solution
50: Volume of prepared sample solution (ml)
w: Sample weight (g)
L: Optical rotation tube length (dm)