Cyclic acetals of ethylene glycol, cis-but-2-ene-1,4-diol and their dichlorocyclopropyl derivatives were synthesized. Compounds simultaneously containing the gem-dichlorocyclopropane 1,3-dioxacycloalkane cycles are shown to exhibit cytotoxic activity against HEK293, SH-SY5Y, HepG2, MCF-7, A549, Jurkat cell lines. The obtained results open up prospects for further studies antitumor 2-(2,2-dichlo...

The synthesis of spirocyclic amide acetals (33–93 %) has been achieved through Ru(II)-catalyzed condensations N-carbamate protected pyrrolidinones with metal carbenes derived from α-diazo-β-ketoesters. Thanks to the mildness diazo decomposition conditions induced by a 1 : combination [CpRu(MeCN)3][BArF] and 1,10-phenanthroline, formation sensitive products is possible. Full characterization thi...

Three new phytoecdysteroid compounds, named niuxixinsterone A (1), B (2) and C (3) with acetal functions in the side-chain were isolated from Achyranthes bidentata Bl. The structures were established as (20R,22R,24S)-20-O,22-O-(5'-hydroxymethyl)-furfurylidene-2β,3β,14α,25-tetrahydroxy-5β-ergost-7-en-6-one (1), (20R,22R)-20-O,22-O-(5'-hydroxymethyl)-furfurylidene-2β,3β,25-trihydroxy-14β-methyl-1...

In(OTf)3-catalyzed robust and sustainable one-pot access to previously unknown and synthetically demanding polysubstituted pyrroles via [3 + 2] annulation of α-oxoketene-N,S-acetals with β-nitrostyrenes has been achieved under solvent-free conditions. The merit of this domino Michael addition/cyclization sequence is highlighted by its operational simplicity, short reaction time (5-10 min), good...

The first total syntheses of (-)-trichorabdal A and (-)-longikaurin E are reported. A unified synthetic strategy is employed that relies on a Pd-mediated oxidative cyclization of a silyl ketene acetal to generate an all-carbon quaternary center and build the bicyclo[3.2.1]octane framework. These studies, taken together with our previous synthesis of (-)-maoecrystal Z, demonstrate that three arc...

Because volatile compounds evaporate from surfaces that are usually exposed to daylight, photoresponsive delivery systems are particularly suitable to control their release. In the present study, we investigated 4,4-diphenyl-4H-benzo[d][1,3]dioxins as profragrances for the light-induced delivery of aldehydes in functional perfumery. The efficiency of fragrance release was investigated on cotton...

An efficient and highly diastereoselective method for the construction of the hydroxylated tropane skeleton is described. The method features a new intramolecular reductive coupling reaction of N-acyl N,O-acetal with aldehyde, cooperatively mediated by BF(3)·OEt(2) and SmI(2). On the basis of this method, a new enantioselective total synthesis of (-)-Bao Gong Teng A has been accomplished.