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Nineteen compounds isolated from Ranunculus sieboldii and Ranunculus sceleratus were tested for inhibitory effects on hepatitis B virus (HBV) and Herpes simplex virus type-1 (HSV-1). The results showed that apigenin 4'- O- alpha-rhamnopyranoside, apigenin 7- O- beta-glucopyranosyl-4'- O- alpha-rhamnopyranoside, tricin 7- O- beta-glucopyranoside, tricin, and isoscopoletin possessed inhibitory activity against HBV replication. Protocatechuyl aldehyde exhibited an inhibiting activity on HSV-1 replication. It is therefore suggested that further investigations on these bioactive compounds might be needed to discover and develop new antiviral agents.

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The solubility of camellianin A (4′,5,7-trihydroxyflavone; 5-O-[R-L-rhamnopyranosyl-(1f4)-6-O-acetyl--D-gluco-pyranoside]) in methanol, acetonitrile, acetone, and water from (283.2 to 313.2) K was measured under atmospheric pressure. The solubility of camellianin A in these solvents increases with increasing temperature. The solubility data were correlated with the Apelblat equation. IntroductionCamellianin A (4′,5,7-trihydroxyflavone; 5-O-[R-L-rhamnopyranosyl-(1f4)-6-O-acetyl--D-glucopyranoside], CAS no. 109232-77-1; Figure 1), a naturally occurring flavone glycoside, largely exists with its content as high as 27.57 % ( 0.92 % in the leaves of Adinandra nitida, a famous folk tea in Guangxi province of P. R. China. 1 Previous pharmacological studies on this compound have demonstrated strong antioxidant activity 1,2 and significant anticancer effects against A431 tumor cells. 3 In addition, the flavonoid-rich methanol extract of the leaves of A. nitida showed remarkable 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, at levels 10-fold higher than that of butylated hydroxytoluene. 4 As camellianin A exhibited antioxidant activity, it could be widely used in the food and pharmaceutical industry as a potential natural antioxidant and a functional ingredient as rutin. 2 In our research, compared to silica gel or macroporous resin, crystallization is the most efficient and economical way to obtain pure camellianin A, in which solvents such as methanol, acetone, and so forth are frequently used. Therefore, the solubility data of camellianin A in different solvents is an important reference in the purification process studies.In the present study, the solubilities of camellianin A in methanol, acetonitrile, acetone, and water over the temperature range of (283.2 to 313.2) K were measured, and the results were fitted with the modified Apelblat equation. Experimental SectionReagents and Apparatus. Camellianin A was isolated from the leaves of A. nitida by silica gel column chromatography. The minimum purity of camellianin A was higher than 99.0 % (the impurity in camellianin A was camellianin B, whose structure is very similar to camellianin A). After exhaustively recrystallization in methanol, the purity was ascertained by high-performance liquid chromatography (HPLC; Waters 2996 HPLC instrument coupled with a 2487 UV detector). The methanol, acetonitrile, and acetone (obtained from Shuanglin Chemical Reagent Factory, Hangzhou, China) were analytical purity grade. Deionized water was distilled before use. A THZ-C shaker was supplied by Taikang Laboratorial Equipment Factory (Henan, China). The absorbance measurements of samples were carried out on a TU-1901 spectrophotometer (Puxi Tongyong Instrument Co. Ltd., Beijing, China). The type of the cuvette is quartz, and the path length is 1 cm.Sample Preparation. Excess amounts of camellianin A were added to 70 mL of the four solvents with their temperatures ranging from (283.2 to 313.2) K. The temperature was controlled by a thermostat (uncertainty of ( 0.1 K) in t...