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Silibinin with a wide range of efficacy, and almost non-toxic, have anti-cancer effects for the treatment of liver diseases such as hepatitis, cirrhosis and many types of cancer, prostate cancer, skin cancer, bladder cancer, lung cancer and colon cancer . Unfortunately it is very low solubility in water, at room temperature only 40mg.L -1 , poor bioavailability. To solve this problem, Scientists around the world have studied the transformation of its structure and synthesis of many derivatives, including the compound (e.g., meglumine, phosphatidyl choline compound, cyclodextrin complexes), polyhydric esters a salt (such as phthalic acid ester salt, a succinate salt, a phosphate salt), glycoside. These studies have certain results, derived from a variety of listed drugs, in varying degrees to improve their bioavailability. The structural transformation of the studies have shown that the molecular structure of silibinin almost can not be reduced, derivatives explore the absence of a breakthrough. In order to improve the the silibinin solubility and bioavailability, we prepared a series of silibinin on 23 primary hydroxyl amino acid derivatives, and preliminary evaluation of their biological activity. First introduced to 5 amino acids in the amino group of glycine, L-alanine, L-phenylalanine, L-leucine and L-serine tert-butyl dicarbonate and sodium hydroxide in tert-butanol tert-butyloxycarbonyl (Boc), such amino-protecting method yields high purity of the product is good, too. Followed by Mitsunobu reaction of diethyl azodicarboxylate (DEAD), triphenylphosphine (TPP) under it with silibinin dehydration condensation of then acid stripped Boc, to obtain the corresponding silymarin Bin 23 acylated product. Solubility experiments show that these acylate hydrochloride solubility in water of silibinin 500 to 1,000 times. Carbon tetrachloride-induced acute liver injury in mice as a model, and preliminary evaluation of the biological activity of the five compounds. The experiments show that the syrup silibinin compared with the positive control, the concentration of 200mg · kg -1 , 23-O-glycyl silymarin Bin ,23-O-phenylalanyl aminoacyl The silibinin ,23-O-leucyl silibinin and 23-O-wire aminoacyl silibinin four acylated product to prevent liver injury better than silibinin and efficacy with with the concentration increases, respectively; 23-O-C aminoacyl silibinin Liver function at low concentrations, but need to reach 300mg · kg -1 concentration, had just shown to be superior the effect of silibinin. And 300mg · kg -1 silibinin 23 acylate group, the five kinds of silybin acylated product single drug concentration of 300mg · kg -1 , serum AST and ALT vitality values ??are close to the normal group, P> 0.05, no difference to prove the safety of the drug.
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