Multilayer Silicene Nanoribbons

The synthesis of silicene, graphene-like silicon, has generated very strong interest. Here, we reveal the growth of high aspect ratio, perfectly straight, and aligned silicon nanoribbons, exhibiting pyramidal cross section. They are multistacks of silicene and show in angle-resolved photoemission cone-like dispersion of their π and π* bands, at the <i>X̅</i> point of their one-dimensional Brillouin zone, with Fermi velocity of ∼1.3 × 10⁶ m sec^–1, which is very promising for potential applications

Discovery of a Novel Series of <i>N</i>‑Phenylindoline-5-sulfonamide Derivatives as Potent, Selective, and Orally Bioavailable Acyl CoA:Monoacylglycerol Acyltransferase‑2 Inhibitors

Acyl CoA:monoacylglycerol acyltransferase-2 (MGAT2) has attracted interest as a novel target for the treatment of obesity and metabolic diseases. Starting from <i>N</i>-phenylbenzenesulfonamide derivative <b>1</b> with moderate potency for MGAT2 inhibition, we explored an effective location of the hydrophobic group at the 1-position to enhance MGAT2 inhibitory activity. Shifting the hydrophobic group to the adjacent position followed by introduction of a bicyclic central core to restrict the substituent orientation produced <i>N</i>-phenylindoline-5-sulfonamide derivative <b>10b</b>, which displayed much improved potency, with an IC₅₀ value of 1.0 nM. This compound also exhibited excellent selectivity (greater than 30,000-fold) against related acyltransferases (MGAT3, DGAT1, DGAT2, and ACAT1). Subsequent optimization efforts were directed toward improving pharmacokinetic profiles, which resulted in the identification of 5-[(2,4-difluorophenyl)­sulfamoyl]-7-(2-oxopyrrolidin-1-yl)-<i>N</i>-[4-(trifluoromethyl)­phenyl]-2,3-dihydro-1<i>H</i>-indole-1-carboxamide (<b>24d</b>) endowed with potent MGAT2 inhibitory activity (IC₅₀ = 3.4 nM) and high oral bioavailability (<i>F</i> = 52%, mouse). In a mouse oral fat tolerance test, oral administration of this compound effectively suppressed the elevation of plasma triacylglycerol levels