LEVODOPA (3,4-DIHYDROXY-L-PHENYLALANINE)

Catecholamine: a group of naturally occurring sympathomimetic amines that have important physiological functions within the body as neurotransmitters in the central nervous system and hormones in the blood circulation. Catecholamines are biogenic amines considered as sympathomimetic drugs; They are characterized by a catechol group [The ortho (1,2) isomer of dihydroxybenzene] to which is attached an amine group (the aromatic portion of whose molecule is catechol, and the aliphatic portion an amine). The most abundant catecholamines in the body are epinephrine (adrenaline), norepinephrine (noradrenaline) and dopamine. They are derived from the tyrosine, an amino acid (protein building block) that is the precursor of norepinephrine. (The prefix nor- describes normal structure which has no branched chain of carbon atoms. In case of norepinephrine, it has one less methylene group than its homologue, epinephrine.) Catecholamines belong to a broader class of compounds called phenethylamines which contain structurally amino acid, phenylalanine and tyrosine. Phenethylamine is a backbone for the compounds which take roles of alkaloids as well as hormones and neurotransmitters in nature. Amphetamine is the substituted phenethylamine by methyl group at alpha position. It is a synthetic drug used as a diet suppressant and to treat narcolepsy and ADHD (attention deficit hyperactivity disorder). But amphetamines can produce severe psychological dependence, including cardiac irregularities and gastric disturbances. Chronic use often results in extreme exhaustion and malnutrition. Substituted phenethylamines are:

LEVODOPA
PRODUCT IDENTIFICATION
CAS NO.	59-92-7
EINECS NO.	200-445-2
FORMULA	(HO)₂C₆H₃CH₂CH(NH₂)COOH
MOL WT.	197.19
H.S. CODE
TOXICITY
SYNONYMS	3,4-Dihydroxy-L-phenylalanine;
[3-(3,4-Dihydroxyphenyl)-L-Alanine]; L-3-(3,4-Dihydroxyphenyl)alanine; 3-hydroxy-L-tyrosine; L-3,4-dihydroxyphenylalanine; L-beta-(3,4-Dihydroxyphenyl)alanine; L-Dihydroxyphenyl-L- alanine;
SMILES
CLASSIFICATION
PHYSICAL AND CHEMICAL PROPERTIES
PHYSICAL STATE	`white to creamy crystalline powder`
MELTING POINT	295 C
BOILING POINT
SPECIFIC GRAVITY
SOLUBILITY IN WATER	Soluble
SOLVENT SOLUBILITY
pH
VAPOR DENSITY
AUTOIGNITION
NFPA RATINGS
REFRACTIVE INDEX
FLASH POINT
STABILITY	Stable under ordinary conditions. Air, light sensitive.
APPLICATIONS
Levodopa, naturally occurring L- form dopa [(-)-3-(3,4-dihydroxy-phenyl)-L-alanine] is used as an anticholinergic drug and used in the treatment of Parkinson's disease in which dopamine deficit is seen. It is used sometimes in combination with carbidopa [(-)-L-(alpha-hydrazino- (alpha-methyl-beta- (3,4-dihydroxybenzene) propanoic acid], an inhibitor of aromatic amino acid decarboxylation and entacapone [(E)-2-cyano-3-(3,4- dihydroxy -5- nitrophenyl)-N,N-diethyl- 2-propenamide], an inhibitor of catechol-O- methyltransferase. L-dopa is produced by oxidation of tyrosine by monophenol monooxygenase in the body. It is decarboxylated to dopamine by the enzyme aromatic-L-amino-acid decarboxylase. It acts as an intermediate in the biosynthesis of other catecholamines (norepinephrine, epinephrine), and melanin. It is a white crystalline powder; slightly soluble in water, in dilute hydrochloric acid and in formic acid; insoluble in ethanol.
SALES SPECIFICATION
BP2000
APPEARANCE	`white to creamy crystalline powder`
IDENTIFICATION	Complies
SOLUTION CLARITY	Complies
pH	4.5 - 7.0
OPTICAL ROTATION	-1.27° ~ -1.34°
HEAVY METALS	10ppm max
SULFATED ASH	0.1% max
LOSS ON DRYING	1.0% max
CONTENT	99.0% - 101.0%
TRANSPORTATION
PACKING
HAZARD CLASS
UN NO.
OTHER INFORMATION
`Hazard Symbols: XN, Risk Phrases:` 22-36/37/38, `Safety Phrases:` 26-36
GENERAL DESCRIPTION OF CATECHOLAMINE
Catecholamine: a group of naturally occurring sympathomimetic amines that have important physiological functions within the body as neurotransmitters in the central nervous system and hormones in the blood circulation. Catecholamines are biogenic amines considered as sympathomimetic drugs; They are characterized by a catechol group [The ortho (1,2) isomer of dihydroxybenzene] to which is attached an amine group (the aromatic portion of whose molecule is catechol, and the aliphatic portion an amine). The most abundant catecholamines in the body are epinephrine (adrenaline), norepinephrine (noradrenaline) and dopamine. They are derived from the tyrosine, an amino acid (protein building block) that is the precursor of norepinephrine. (The prefix nor- describes normal structure which has no branched chain of carbon atoms. In case of norepinephrine, it has one less methylene group than its homologue, epinephrine.) Catecholamines belong to a broader class of compounds called phenethylamines which contain structurally amino acid, phenylalanine and tyrosine. Phenethylamine is a backbone for the compounds which take roles of alkaloids as well as hormones and neurotransmitters in nature. Amphetamine is the substituted phenethylamine by methyl group at alpha position. It is a synthetic drug used as a diet suppressant and to treat narcolepsy and ADHD (attention deficit hyperactivity disorder). But amphetamines can produce severe psychological dependence, including cardiac irregularities and gastric disturbances. Chronic use often results in extreme exhaustion and malnutrition. Substituted phenethylamines are: