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  • Chemical Name:L-Isoleucine
  • CAS No.:73-32-5
  • MF:C6H13NO2
  • MW:131.17
  • Purity:>98% or As customer requested
  • Color:White to Off-white
  • Product Categories:Biochemistry;Nutritional Supplements;L-Amino Acids;Amino Acids; APIs; Biochemical Engineering
  • Test method: HPLC


What is L-isoleucine?

L-isoleucine is the L-enantiomer of isoleucine. It has a role as a Saccharomyces cerevisiae metabolite, an Escherichia coli metabolite, a plant metabolite, a human metabolite, an algal metabolite and a mouse metabolite. It is an aspartate family amino acid, a proteinogenic amino acid, an isoleucine and a L-alpha-amino acid. It is a conjugate base of a L-isoleucinium. It is a conjugate acid of a L-isoleucinate. It is an enantiomer of a D-isoleucine. It is a tautomer of a L-isoleucine zwitterion. (Source: ChEBI)

Basic information   

Product Name: L-Isoleucine
Synonyms: Isoleucine; (S)-Isoleucine; L-(+)-Isoleucine; Isoleucinum; Isoleucina; 
CAS: 73-32-5
MF: C6H13NO2
MW: 131.17
EINECS: 200-798-2
Product Categories: Biochemistry;Nutritional Supplements;L-Amino Acids;Amino Acids; APIs; Biochemical Engineering
Chemical Structure


Chemical Properties   

Melting point  288 °C (dec.) (lit.)
alpha  41 º (c=4, 6N HCl)
Boiling point  225.8±23.0 °C(Predicted)
density  1.2930 (estimate)
refractive index  40.5 ° (C=4, 6mol/L HCl)
Fp  168-170°C
storage temp.  Store below +30°C.
solubility  1 M HCl: 50 mg/mL
pka 2.32, 9.76(at 25℃)
form  powder
color  White to Off-white
PH 5.5-6.5 (40g/l, H2O, 20℃)
optical activity [α]20/D +41.0±1°, c = 5% in 6 M HCl
Water Solubility  41.2 g/L (50 ºC)
λmax λ: 260 nm Amax: 0.07
λ: 280 nm Amax: 0.05
Sublimation  168-170 ºC
Merck  14,5179
JECFA Number 2118
BRN  1721792
Usage And Synthesis

L-Isoleucine Uses            
L-Isoleucine is one of the essential amino acids that cannot be made by the body and is known for its ability to help endurance and assist in the repair and rebuilding of muscle. This amino acid is important to body builders as it helps boost energy and helps the body recover from training.
L-Isoleucine is also classified as a branched-chain amino acid (BCAA). There are three branched-chain amino acids in the body, with the others being L-Valine, and L-Leucine, and all of them help promote muscle recovery after exercise. Isoleucine is actually broken down for energy within the muscle tissue.

Maxmedchem, a global supplier of L-Isoleucine, 73-32-5 offers for your requirements of RND / Development quantities or commercials, based on status of the product. 

a) Free sample can be supplied.

b) Guide our clients by professional knowledge and teach them how to use our product after sales.

c) Accept SGS,BV any other third-party inspection before loading.

d) High quality best price Guaranteed.

MSDS: MSDS available.

COA: COA can be available if you send us inquiry.

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Packaging and Shipping




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