Despite lots of recent impressive reports on chalcones [8, 9] and 5-deoxyflavonoids [10], the full potential of such class of compounds is yet to be realized in terms of both more new molecules as check FAQ drugs and varied biological activity. This situation is largely due to their simple chemical structure and useful template. It has recently become more apparent that most of the important classes of drugs, especially those derived from natural products, are glycosides having a sugar moiety linked to an aglycon through an O- or C-glycosidic bond. In our continued efforts to use natural products only as synthetic templates and thereby replace the original plant sources with synthetic ones and investigate structure-activity relationship, herein, we wish to report the synthesis and cytotoxicity bioassays of a series of chalcones 1~8 and 5-deoxyflabonoids 9~16 as well as their glycoside derivatives 17~22.

Among them, 13 and 17~22 are new compounds.2. Results and DiscussionScheme 1 outlines the synthesis of chalcones 1~8 and 5-deoxyflavonoids 9~22, starting from appropriate benzaldehydes 23~27, 33, 34, and acetyl phenols substituted by methoxy or methoxymethoxy, which were purchased or prepared with an improved traditional method in good yields. In the synthesis process, the methoxymethoxy group was chosen to protect the OH group, because it is stable in basic environment and easy to deprotect. Chalcones 28~32 were prepared by using aldol condensation of appropriate substituted benzaldehydes 23~27, 33, 34, and acetyl phenols in KOH/EtOH and deprotection reaction.

The aldol condensation was very sensitive to modification of reaction parameters. A significant excess of KOH (10~15 equiv) was required to force the reaction to completion. Flavonols 9~16 were prepared by classic Algar-Flynn-Oyamada reaction treating the corresponding chalcones with 15% H2O2 and 16% NaOH (aq) and deprotection reaction.Scheme 1It is well know Batimastat that sugar moiety could enhance water solubility and improve the targeting activity of bioactive molecules [11]. For example, lactose can be recognized by the hepatic asialoglycoprotein receptor (ASGP-R), and ASGP-R localized to liver cells provides an efficient entry point for lactose-modified molecules [12]. The modification of 5-deoxyflavonoids with lactose may be possible to specifically target molecules to liver cells, facilitating application of bioactive 5-deoxyflavonoids to the treatment of hepatitis B, hepatitis C, and liver cancer. On the other hand, the largely hydrophobic character of 5-deoxyflavonoids makes it poorly soluble in aqueous media which in some cases limits their therapeutic efficacy, and this has a strong influence on their pharmacokinetic properties.