Yb(OTf)(3)-catalyzed equimolar condensation of the benzylated catechin with various 4-alkoxy catechin derivatives was studied. In particular, the reaction using 4-(2''-ethoxyethoxy)flavan derivative gave good yield with excellent stereoselectivity. The condensed product was successfully converted to procyanidin B3 (1). The anti-inflammatory effect of procyanidin B3 (1) on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation of mouse ears was examined. The anti-inflammatory activity of 1 was stronger than that of indomethacin and glycyrrhetinic acid, the normally used anti-inflammatory agents.

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The diffusion of metal particles into a silicon oxide layer during chemical vapor deposition causes various carbon nanotube growth modes. Here, the diffusion behavior of Co and Fe layers sandwiched between silicon oxides was investigated. The Co layer does not diffuse, while the Fe layer diffuses when annealed in Ar/H 2 . The thermal behavior also depends on the ambient gas. The diffusivity of Fe and the nondiffusivity of Co when annealed in Ar/H 2 can be explained by ionic radius and valence requirements. Fe 3+ , which has a similar ionic radius to Si 4+ , can thermally diffuse via the substitution of Si 4+ at the center of SiO 4 tetrahedra with an oxygen vacancy, whereas Co 2+ does not diffuse through substitution owing to its larger ionic radius and strict requirements for two oxide vacancies in SiO 4 tetrahedra.

-Synthesis of procyanidin C2 and C1 was achieved via a stereoselective intermolecular condensation of equimolar amount of dimeric catechin or epicatechin nucleophile and monomeric catechin or epicatechin electrophile using Lewis acid. In the case of synthesis of procyanidin C2, AgBF 4 and AgOTf afforded condensed product in excellent yield. As to the synthesis of procyanidin C1, Yb(OTf) 3 was effective for equimolar condensation.

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