Product Code：P006063
English Name：Pregabalin Impurity 63
English Alias：3-cyano-5-methylhexanoic acid
CAS No.：181289-16-7
Molecular Formula：C₈H₁₃NO₂
Molecular Weight：155.19
High-Purity Guarantee：Confirmed by HPLC (≥99.0%) and verified by multiple methods including NMR (1H, 13C), HRMS, and elemental analysis, providing a reliable standard for Pregabalin impurity analysis.
Excellent Stability：Stable for 36 months under storage conditions of -20℃ in the dark and sealed. The degradation rate is less than 0.3% within 6 months in common solvent systems such as methanol - water, ensuring stable and repeatable experimental data.
Quality Control Testing：Used for UPLC-MS/MS detection of Impurity 63 in Pregabalin API and formulations. Strictly control the impurity content to meet ICH Q3A standards (single impurity limit ≤0.1%), ensuring drug quality and safety.
Process Optimization Research：Monitor the formation pathway of this impurity during the synthesis of Pregabalin. By adjusting parameters such as cyanidation reaction temperature (e.g., 40 - 50℃), reaction time, and reactant ratio, the generation of impurities can be reduced by more than 35%.
Method Validation：As a standard for developing impurity detection methods, it can verify the resolution (≥3.0) and limit of detection (0.01 ng/mL) of UPLC, ensuring the accuracy and sensitivity of the detection method.
Pregabalin, a γ-aminobutyric acid (GABA) analog, is mainly used to treat postherpetic neuralgia, partial-onset epilepsy, and generalized anxiety disorder. It works by regulating voltage-gated calcium channels in the central nervous system to reduce neurotransmitter release. Impurity 63, a process-related impurity in Pregabalin synthesis, may originate from cyanidation or alkylation side reactions of intermediates. Its cyano and carboxyl groups may affect drug chemical stability, biological activity, and safety. Given the extremely strict impurity control requirements for nervous system drugs, the study of this impurity is crucial for ensuring the quality of Pregabalin drugs.
Detection Technology：UPLC-MS/MS technology is used, combined with a C18 column (1.7μm) and gradient elution with 0.1% formic acid - acetonitrile. Impurities can be separated within 5 minutes, and the limit of detection is as low as 0.003 ng/mL, enabling high-precision detection of trace impurities.
Formation Mechanism：Studies have shown that this impurity is formed by the reaction of 5-methylhexanoic acid with cyanide reagents under the action of an alkaline catalyst (such as sodium carbonate). Optimizing the catalyst dosage and reaction pH can effectively inhibit side reactions.
Safety Evaluation：In vitro cytotoxicity experiments show that the IC₅₀ of this impurity against SH-SY5Y nerve cells is 186.7 μM (Pregabalin IC₅₀ = 12.5 μM). Although the toxicity is lower than that of the main drug, its content in drugs still needs to be strictly controlled. Currently, long-term stability tests are being carried out to systematically study its degradation characteristics under high temperature, high humidity, and light conditions.
China
