Ganirelix, a peptide-based drug used to treat female infertility, has been in high market demand, which attracted generic formulation. A hitherto unknown impurity of ganirelix was observed in our formulation process, which reached ~0.3% in 6 months and led to a detailed investigation of its structure. In-depth analysis of ESI-MS/MS data of this impurity coupled with an artificial intelligence prediction tool led to a highly unusual putative structure, that is, N-(2-carboxyethyl)-ganirelix (^NCE-GA), which was authenticated by chemical synthesis from ganirelix and NMR analysis and via corroborated HPLC and MS/MS data with the formulation-derived impurity.

中文翻译：

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注射用加尼瑞克制剂中前所未有的 N-(2-羧乙基) 加合物杂质的鉴定、合成和表征

加尼瑞克（Ganirelix）是一种用于治疗女性不孕症的肽类药物，市场需求量很大，吸引了仿制药。在我们的配方过程中观察到一种迄今为止未知的加尼瑞克杂质，该杂质在 6 个月内达到约 0.3%，因此对其结构进行了详细研究。对该杂质的 ESI-MS/MS 数据进行深入分析，并结合人工智能预测工具，得出了一个极不寻常的假定结构，即N -(2-羧乙基)-ganirelix ( ^N CE-GA)，通过加尼瑞克的化学合成和 NMR 分析以及通过制剂衍生杂质的 HPLC 和 MS/MS 数据进行验证。