A bifunctional silane, 3-((3-(trimethoxysilyl)propyl)thio)propane-1-sulfonic acid (TESAS), was designed for incorporation into SBA-15-type silica by co-condensation. To achieve mesopore ordering in the functionalized silica, the standard SBA-15 synthetic protocol was modified, resulting in well-formed hexagonal particles. In a variation, the thioether group of TESAS was oxidized by H2O2 to the sulfone during the synthesis of the modified SBA-15. The presence, concentration, and location of functional groups were assessed by elemental analysis, potentiometric titration, and 13C and 29Si CP/MAS NMR spectroscopy. Pore structure and particle morphology were observed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and powder X-ray diffraction (XRD). The materials were studied and compared in the selective dehydration of fructose to 5-hydroxymethylfurfural (HMF). Interestingly, the thioether-containing TESAS-SBA-15 shows higher activity in the dehydration of aqueous fructose, as well as higher selectivity toward HMF (71% at 84% conversion) than its sulfone derivative, possibly because of its more hydrophobic nature.

A supported, single-site Lewis acid, ≡SiOB(C(6)F(5))(2), was prepared by water-catalyzed grafting of B(C(6)F(5))(3) onto the surface of amorphous silica, and its subsequent use as a cocatalyst for heterogeneous olefin polymerization was explored. Although B(C(6)F(5))(3) has been reported to be unreactive toward silica in the absence of a Brønsted base, we find that it can be grafted even at room temperature, albeit slowly. The mechanism was investigated by (1)H and (19)F NMR, in both the solution and solid states. In the presence of a trace amount of H(2)O, either added intentionally or formed in situ by borane-induced dehydration of silanol pairs, the adduct (C(6)F(5))(3)B·OH(2) hydrolyzes to afford C(6)F(5)H and (C(6)F(5))(2)BOH. The latter reacts with the surface hydroxyl groups of silica to yield ≡SiOB(C(6)F(5))(2) sites and regenerate H(2)O. When B(C(6)F(5))(3) is present in excess, the resulting grafted boranes appear to be completely dry, due to the eventual formation of [(C(6)F(5))(2)B](2)O. The immobilized, tri-coordinate Lewis acid sites were characterized by solid-state (11)B and (19)F NMR, IR, elemental analysis, and C(5)H(5)N-TPD. Their ability to activate two molecular C(2)H(4) polymerization catalysts, Cp(2)ZrMe(2) and an (α-iminocarboxamidato)nickel(II) complex, was explored.

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Hypertension generally requires the use of a combination therapy to achieve the satisfactory control of blood pressure. A traditional Chinese herb, Danshen (Salvia miltiorrhiza), has been shown to have cardioprotective effects in animals and humans. The study investigated the add-on effect of Fufang Danshen extract capsule in Taiwanese hypertensive patients with uncontrolled blood pressure. This was a double-blind, placebo-controlled, randomized, single-center study clinical trial. Fifty-five patients with uncontrolled mild to moderate hypertension were enrolled under current conventional antihypertensive treatment, randomized equally to receive a Fufang Danshen capsule (formula mixture) 1000 mg twice-daily or a placebo capsule for 12 weeks. Primary endpoints were the control rate and the response rate. By ITT analysis at week 12, the control rates were 25.5% in the Fufang Danshen group and 7.3% in the control group (p = 0.016). The response rates were 45.6% in the Fufang Danshen group and 38.2% in the placebo group (p = 0.946). A significant reduction of systolic blood pressure at week 12 was noted in the Fufang Danshen group compared with the placebo group (13.8 vs 4.2 mmHg, p = 0.005). A decrease of pulse rate was also noted in the Fufang Danshen group (- 3.2 vs +2.7/min, p = 0.027). Adverse events were not statistically different between the two groups. It was concluded that Fufang Danshen (Salvia miltiorrhiza) extract reduced systolic blood pressure and pulse rate, and was well tolerated in patients with hypertension.