Total synthesis of Sparstolonin B, a potent anti-inflammatory agent

Abstract

Two concise routes for the first total synthesis of Sparstolonin B (SsnB) have been described. The synthesis of SsnB could be accomplished in 5 and 6 steps with 40% and 38% overall yield, respectively. The rhodium-catalysed oxidative coupling of benzoic acid with internal alkyne was used in both strategies to construct the core structure of SsnB.Sparstolonin B (SsnB) is the rst novel bioactive natural small molecule, isolated from a Chinese herb, Sparganium stoloniferum, by Liang and coworkers, which selectively blocks toll-like receptors 2 (TLR2) and TLR4 mediated inammatory signalling by inhibiting the recruitment of MyD88 to the Toll/Il-1 receptor homologue domains of TLR2 and TLR4.

Recent Advances in [Cp*MIII] (M = Co, Rh, Ir)‐Catalyzed Intramolecular Annulation Through C–H Activation

“…The Rh III ‐catalyzed intramolecular oxidative coupling of tethered alkynes has also been performed using a carboxylic acid as directing group to form isocoumarin skeletons. This strategy has been used by Wang and Sun, for the total synthesis of sparstolonin B, a potent anti‐inflammatory agent (Scheme ) . After preparation of the alkyne‐tethered benzoic acid derivative 53 , the carboxylic acid was treated with 10 mol‐% of [Cp*RhCl 2 ] 2 and a stoichiometric amount of silver carbonate, which plays both the role of a base and an oxidant.…”

Core-double shell ZnO/ZnS@Co3O4 heterostructure as high performance pseudocapacitor

“…5(a). [57][58][59][60][61][62][63][64] The specific capacitance is further enhanced to 777 F g −1 in the case of ZnO/ZnS@Co 3 O 4 which is 10 times higher than that of a commercial Co 3 O 4 -based super- capacitor. Specific capacity values calculated from eqn (1) follow the order ZnO < Co 3 O 4 < ZnO@Co 3 O 4 < ZnO/ZnS@Co 3 O 4 with values of 90 C g −1 , 179 C g −1 , 296 C g −1 and 317 C g −1 respectively.…”

“…ZnS on ZnO augments the charge transfer process in two ways. [57][58][59][60][61][62][63] Long cycle life and the ability to deliver reasonable capacitance at high rates are the two most sought-after attributes of a supercapacitor. 55 Secondly, the band alignment of ZnO@ZnS heterostructures enhances the charge transfer process as described in the schematic shown in Fig.…”

Preparation of a fluid diversion agent for profile control in elevated temperature and high salinity reservoirs

“…The fluid diversion agent can block the fractures and high permeability channels induced by extensive water injection, which subsequently diverts the injected water to the low permeability layers, thus expanding the sweep volume and improving water flooding oil recovery. Therefore, an in‐depth fluid diversion agent for profile control is important for solving the inefficient circulation of injected water and improving water injection efficiency 1–3 . Organic gels for profile control are commonly used to improve water‐flooding efficiency 4 .…”