Semi-synthetic Derivatives of Limonin A: Synthesis Using Basic Hydrolysis and Reduction with NaBH4


Limonin A (L-A) was obtained from seeds of Citrus sinensis that were dried, grounded, and extracted using Soxhlet equipment. Initially, 100% hexane was used to eliminate fats, and finally, 100% dichloromethane was used in order to concentrate and isolate the compound. L-A recrystallization was performed using acetic acid. The purified fraction was identified as limonin according to spectral nuclear magnetic resonance (NMR) data. Two reactions were performed from L-A: Basic hydrolysis that acted on the A’ lactone ring producing a sodium salt of the lactone, and reduction with NaBH4 to reduce the carbonyl of carbon C-7 and generate the corresponding alcohol limonol. The structural modification of abundant secondary metabolites can become a source of new products with biological activity, useful in the pharmaceutical, cosmetic, and agrochemical industries of natural origin.

Keywords: limonin, semisynthetic derivates, bioactive compounds, non-timber forest products.


La limonina A (L-A) se obtuvo a partir de semillas de Citrus sinensis, que fueron secadas, molidas y extraídas en equipo Soxhlet, utilizando inicialmente hexano al 100% para eliminar grasas y finalmente diclorometano al 100% para concentrar y aislar el compuesto. La re cristalización de la L-A se realizó utilizando ácido acético. La fracción purificada se identificó como limonina, acorde a los datos espectrales de RMN (Resonancia Magnética Nuclear). A partir de la Limonina A se realizaron dos reacciones: Hidrólisis básica que actuó sobre el anillo de lactona A’ produciendo la sal sódica de lactona y reducción con NaBH4 para reducir el carbonilo del carbono C-7 y generar el correspondiente alcohol limonol. La modificación estructural de metabolitos secundarios abundantes puede convertirse en una fuente para generar nuevos productos con actividad biológica, útiles en las industrias farmacéutica, cosmética y agroquímica de origen natural.

Palabras Clave: Limonina; derivados semisintéticos, compuestos bioactivos, productos forestales no maderables.

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