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Lactols II , obtained by DIBAL reduction of their corresponding lactones I , in equilibrium with their hydroxyaldehyde tautomers III were used in a three-component reductive alkylation with 2-hydroxy-1,4-naphthoquinone to give a series of 3-alkylated 2-hydroxy-1,4-naphthoquinone derivatives IV . [ABSTRACT FROM AUTHOR]

Monofluorinated 3-alkyl-2-hydroxy-1,4-naphthoquinone 4 was prepared in eight steps from commercially available 8-bromooctanoic acid ( 10 ). The key step involved l -proline-catalyzed three-component reductive alkylation (TCRA) of 2-hydroxy-1,4-naphthoquinone ( 5 ) with the optically active aldehyde 7 . [ABSTRACT FROM AUTHOR]

A six step synthesis of furano abietane cyano enone 12 is described, in which the key step is a palladium-catalyzed intramolecular Heck reaction of bromo 3-phenoxyacrylate 17, prepared from enone phenol 13 in high yield. [ABSTRACT FROM AUTHOR]

Abstract: 2-Cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid (CDDO, 2) was condensed with various amino acid methyl esters at the C-28 carboxylic acid. The new amide conjugates were evaluated for their inhibition of nitric oxide (NO) production in RAW264.7 cells stimulated with interferon-γ (IFNγ). Of these new compounds, CDDO conjugates with alanine, valine, and serine are nearly equipotent to CDDO-ethyl amide (4), a triterpenoid with promising biological activity in numerous disease models. Some of these conjugates also induce the in vitro expression of heme oxygenase-1, and inhibit the proliferation of Panc-1343 pancreatic cells. [Copyright &y& Elsevier]

• Synthesis of a phenylene-fused dimer of anthracene. • A mimic of hexacene that is stable. • Electronic properties show through-conjugation but not a fully conjugated acene. We describe the synthesis and electronic properties of the novel interrupted hexacene 5,16-diphenylcyclobuta[1,2- b :3,4- b ′]dianthracene (1). The synthesis is rooted in a sequential twin Sonogashira coupling of 2,3-dibromo-9,10-dihydro-9,10-epoxyanthracene followed by a Vollhardt 2+2+2 cyclotrimerization to give o- bromoaryl(trimethylsilyl) 8 , after selective bromination. A Diels-Alder cycloaddition of the aryne from 8 and 1,3-diphenylisobenzofuran gave 1 after deoxygenation. Photophysical studies suggest that the fused cyclobutane ring been the two anthracene rings allows through-conjugation, but does not allow 1 to behave as a conjugated acene. Attempts to synthesize the parent analogue, cyclobuta[1,2- b :3,4- b ′]dianthracene (2) were not successful, but detailed calculations are reported for both 1 and 2. [ABSTRACT FROM AUTHOR]