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Bioavailability Enhancement of Silybin Through Carbon-23 Acid Derivatization

Lena Nawzad Amin1, Mohammed N. Sabir2, Emad Manhal Al-Khafaji3 &  Shwan Rachid4

1,2 School of Pharmacy, Dept. of Pharmacognosy & Pharmaceutical Chemistry, Sulaimani University
3 Faculty of Science, Dept. of Chemistry University of Sulaimani
4 Faculty of Sciences and Health,Koya University

Silybin is an isomer derived from the seed of Silybum marianum, a biennial metropolitan
plant that is grown naturally in Iraqi Kurdistan Region, it shows antioxidant and
anticancer activity however; its poor water solubility encounters to low bioavailability
which limits its use in clinical practice. To improve water solubility thereby
bioavailability, a chemical derivatization (carboxylic acid) on C-23 (C27H24O12) was
performed. Silybin derivative on C-23 as ether function improves solubility through
increasing the ability to donate unshared electron pairs like Lewis base. The elongated
carbon chain 25 as carboxylic acid increases the polarity of our derivative in water as
well as the acidity. Our derivative was prepared by Williamson method and showed
improvement of water solubility in comparison to silybin; this will lead to enhance the
bioavailability and consequently the activity of the drug. Structure elucidation confirmed
by FTIR, 13C-NMR and mass spectroscopy. The solubility assessment was performed
according to Beer’s-Lambert law.
Aim: Enhance water solubility and bioavailability of silybin through acid derivatization.

Key Words: Silybin, Solubility, Chemical derivatization, Mass-spectroscopy, Bioavailability


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