Isoparvifuran isolated from Dalbergia odorifera attenuates HO-induced senescence of BJ cells through SIRT1 activation and AKT/mTOR pathway inhibition.

Isoparvifuran is a benzofuran compound isolated from the heartwood of Dalbergia odorifera. Related research reported that isoparvifuran has antioxidant property. However, it is unclear whether isoparvifuran has anti-aging effects.

Application of (4+3) cycloaddition strategies in the synthesis of natural products.

(4+3) Cycloadditions have been widely applied in synthesis, and in this review article, we summarize some of the more recent applications, including formal (4+3) cycloadditions, in the synthesis of natural products. Many of these natural product target frameworks have cycloheptane subunits, for which the (4+3) cycloaddition is a convergent strategy for their assembly. Some natural product targets do not possess seven membered rings, and their syntheses have exploited the functional group endowed (4+3) cycloadducts resulting from these reactions, highlighting the utility of this methodology for the synthesis of a range of complex molecules.

Highly selective gem-difluoroallylation of organoborons with bromodifluoromethylated alkenes catalyzed by palladium.

A first example of Pd-catalyzed gem-difluoroallylation of organoborons using 3-bromo-3,3-difluoropropene (BDFP) in high efficiency with high α/γ-substitution regioselectivity has been developed. The reaction can also be extended to substituted BDFPs and has advantages of low catalyst loading (0.8 to 0.

Construction of Optically Active Quaternary Propargyl Amines by Highly Enantioselective Zinc/BINOL-Catalyzed Alkynylation of Ketoimines.

A general and efficient method for the highly enantioselective alkynylation of ketoimines through a zinc/1,1'-bi-2-naphthol (BINOL)-catalyzed process has been developed. A variety of ketoimines, including α-fluoroalkyl α-imine esters, α-aryl α-imine esters, and trifluoromethyl aryl ketoimines, are applicable and provide their corresponding quaternary propargyl amines in excellent yields with high ee values (up to 99 % ee). Both the steric and electronic effects of substituents at the 3,3' positions of BINOL are critical for the reaction efficiency and enantioselectivity.

(S)-6-{[(S)-2,2-Dimethyl-1,3-dioxolan-4-yl]meth-yl}-5,5-difluoro-5,6-dihydro-2H-pyran-2-one.

The title compound, C(11)H(14)F(2)O(4), is a γ,γ-gem-difluorinated α,β-unsaturated δ-lactone. The dioxolane five-membered ring and the lactone ring adopt half-chair conformations. There are two inter-molecular C-H⋯O inter-actions involving the carbonyl group as an acceptor which stabilize the crystal structure.