Comparative study on inhibitory effects of ginsenosides on human pancreatic lipase and porcine pancreatic lipase: structure-activity relationships and inhibitory mechanism

The inhibitory effects of twenty-six ginsenosides on human pancreatic lipase (hPL) and porcine pancreatic lipase (pPL) were studied. Study reveals that nine ginsenosides have moderate inhibitory effects against hPL, and good selectivity over pPL. By contrast, (S)-Rh2 showed good inhibitory effects on pPL over hPL. SAR analysis indicated that introduction of the O-glycosyl group(s) at C-3/C-7 site is unbeneficial for hPL inhibition, ginsenosides with A-skeleton is more beneficial than ginsenosides with B-/C-skeleton. Inhibition kinetic analysis indicated that Rg3 and (S)-Rh2 inhibited hPL-catalyzed DDAO-ol hydrolysis in a mixed manner. Molecular docking studies have confirmed that Rg3 and (S)-Rh2 inhibit hPL via many Pi-hydrogen interactions and hydrogen bonds with catalytic residues of hPL. These results indicated that pPL as an enzyme source could not fully represent the inhibitory effect of the tested compounds on hPL, and hPL should be used as far as possible to evaluate the inhibitory effect of PL.</p

Gold-Catalyzed Tandem [3,3]-Propargyl Ester Rearrangement Leading to (<i>E</i>)‑1<i>H</i>‑Inden-1-ones

An efficient method for the synthesis of (<i>E</i>)-1<i>H</i>-inden-1-ones using gold-catalyzed tandem [3,3]-propargyl ester rearrangement followed by Michael addition under mild reaction conditions has been developed. The resulting products are important frameworks found in numerous natural products and pharmaceutically active compounds, as well as being valuable intermediates in organic synthesis

Gold-Catalyzed Tandem [3,3]-Propargyl Ester Rearrangement Leading to (<i>E</i>)‑1<i>H</i>‑Inden-1-ones

An efficient method for the synthesis of (<i>E</i>)-1<i>H</i>-inden-1-ones using gold-catalyzed tandem [3,3]-propargyl ester rearrangement followed by Michael addition under mild reaction conditions has been developed. The resulting products are important frameworks found in numerous natural products and pharmaceutically active compounds, as well as being valuable intermediates in organic synthesis

Gold-Catalyzed Tandem [3,3]-Propargyl Ester Rearrangement Leading to (<i>E</i>)‑1<i>H</i>‑Inden-1-ones

An efficient method for the synthesis of (<i>E</i>)-1<i>H</i>-inden-1-ones using gold-catalyzed tandem [3,3]-propargyl ester rearrangement followed by Michael addition under mild reaction conditions has been developed. The resulting products are important frameworks found in numerous natural products and pharmaceutically active compounds, as well as being valuable intermediates in organic synthesis

Palladium-Catalyzed Acylation/Alkenylation of Aryl Iodide: A Domino Approach Based on the Catellani–Lautens Reaction

A new palladium-catalyzed three-component coupling involving acylation/alkenylation of aryl iodide is reported. The reaction was carried out with readily available starting materials and gave the ortho-acylated styrene in moderate to good yields. Compared with previous Catellani–Lautens reactions, this reaction is the first example of introducing an acyl group at the ortho position of aryl iodides. The proposed Pd^IV complex, generated via oxidative addition of the carboxylic anhydrides, is a key intermediate for this transformation

BF₃·OEt₂‑AgSCF₃ Mediated Trifluoro­methyl­thiolation/Cascade Cyclization of Propynols: Synthesis of 4‑((Trifluoro­methyl)­thio)‑2<i>H</i>‑chromene and 4‑((Trifluoro­methyl)­thio)-1,2-dihydro­quinoline Derivatives

A BF₃·OEt₂–AgSCF₃ mediated direct trifluoro­methyl­thiolation/cascade cyclization of propynols involving the SCF₃ anion nucleophilic pathway is developed. This protocol also provides an opportunity to construct valuable trifluoromethylthio-substituted 2<i>H</i>-chromene and 1,2-dihydroquinoline systems with high efficiency under mild conditions. Additionally, the developed BF₃·OEt₂–AgSCF₃ reaction system could be scaled up to gram quantities in a satisfactory yield without inert gas protection