General Information

Carbidopa Impurities and Carbidopa 

Daicel Pharma synthesizes high-quality Carbidopa impurities like (S)-Carbidopa ethyl ester, (S)-Carbidopa methyl ester, 3-Methylcinnoline-6,7 diol, Carbidopa EP Impurity C, Carbidopa EP Impurity H, Carbidopa EP Impurity I, and Carbidopa EP Impurity J, which are crucial in the analysis of the quality, stability, and biological safety of the active pharmaceutical ingredient Carbidopa. Moreover, Daicel Pharma offers custom synthesis of Carbidopa impurities and delivers them globally.

Carbidopa [CAS: 28860-95-9] is a medicine to treat Parkinson’s disease. It belongs to a class of drugs known as decarboxylase inhibitors. Carbidopa is a synthetic form of the neurotransmitter dopamine and is the levorotatory isomer of a hydrazine derivative.

Carbidopa: Use and Commercial Availability  

Carbidopa is a medication used in combination with levodopa to treat motor symptoms associated with Parkinson’s disease, post-encephalitic parkinsonism, and parkinsonism symptoms caused by carbon monoxide or manganese intoxication. It is added to levodopa formulations to decrease the conversion of levodopa to dopamine outside the brain, lower gastrointestinal side effects, and improve levodopa’s effectiveness in the central nervous system. Carbidopa is available under brand names like Dhivy, Duopa, Lodosyn, Rytary, Sinemet, and Stalevo.

Carbidopa Structure and Mechanism of Action

The chemical name of Carbidopa is L-α-Hydrazino-α-methyl-β-(3,4-dihydroxyphenyl)propionic acid. Its chemical formula is C₁₀H₁₄N₂O₄, and its molecular weight is approximately 226.23 g/mol.

Carbidopa inhibits peripheral decarboxylation of levodopa, the metabolic precursor of dopamine. It prevents levodopa from breaking down into dopamine in areas outside the brain, which helps decrease the harmful effects of levodopa on the body.

Carbidopa Impurities and Synthesis

During the manufacturing^1,2 of Carbidopa, impurities form that can be harmful and must be carefully monitored and controlled during production. The factors that influence the formation of these impurities include reaction conditions, storage conditions, and the quality of raw materials used in the manufacturing process.

Daicel provides a Certificate of Analysis (CoA) for Carbidopa impurity standards, including (S)-Carbidopa ethyl ester, (S)-Carbidopa methyl ester, 3-Methylcinnoline-6,7 diol, Carbidopa EP Impurity C, Carbidopa EP Impurity H, Carbidopa EP Impurity I, and Carbidopa EP Impurity J. The CoA is issued from a cGMP-compliant analytical facility and contains complete characterization data, such as 1H NMR, 13C NMR, IR, MASS, and HPLC purity³. Additional characterization data, such as 13C-DEPT and CHN, can be provided upon request. Daicel can also prepare any unknown Carbidopa impurity or degradation product. We give a complete characterization report on delivery.