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Research has been conducted on the fluoride-containing building block preparation and their synthetic transformation. The authors report the exploration of the reactions with nucleophiles.

Bioassay-guided isolation of cultures of Aspergillus sp. TJ23 yielded a novel terpene-polyketide hybrid spiromeroterpenoid, spiroaspertrione A (1), bearing a unique spiro[bicyclo[3.2.2]nonane-2,1'-cyclohexane] carbocyclic skeleton, and a new biointermediate, andiconin B (2). Their structures and absolute configurations were elucidated by spectroscopic analyses, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Compound 1 demonstrated potent resensitization of oxacillin against methicillin-resistant Staphylococcus aureus by lowering the oxacillin minimal inhibitory concentration up to 32-fold from 32 to 1 μg/mL. [ABSTRACT FROM AUTHOR]

With the combination of Pd(dppf)Cl2 and Cu(OAc)2, a variety of 5-iminopyrrolones were synthesized in moderate to good yields from terminal alkynes, isocyanide, and water via isocyanide double insertion and cycloaddition reaction. A plausible reaction mechanism for this process is depicted. Furthermore, selected compounds 3c, 3e, and 3h exhibited good activities against HepG2 (human liver cancer), NCI-H460 (human lung cancer), and SK-OV-3 (human ovarian cancer) cell lines with IC50 values in the range of 10.63-22.63 μmol L-1. [ABSTRACT FROM AUTHOR]

A novel and efficient method for the construction of the pyrazolo[5,1-a]isoindole scaffold via a one-pot three-component cascade reaction of 1-(2-bromophenyl)buta-2,3-dien-1-one with hydrazine and isocyanide promoted by a Pd catalyst is described. This cascade process proceeds through initial condensation of the allenic ketone with hydrazine followed by Pd-catalyzed isocyanide insertion into the C-Br bond and intramolecular C-N bond formation. Interestingly, when acetohydrazide was used in place of hydrazine, a more sophisticated procedure involving condensation, isocyanide insertion into C-H and C-Br bonds, deacetylation, and formation of C-C, C-O, and C-N bonds occurred to afford pyrazolo[5,1-a]isoindole-3-carboxamides with good efficiency. [ABSTRACT FROM AUTHOR]

A one-pot procedure for the synthesis of 3-alkynylpyridines via a zinc-mediated tandem reaction of nitriles with propargyl bromides under extremely mild reaction conditions has been developed. This reaction exhibits high efficiency, broad substrate scope, and good functional group tolerance. In addition, the 3-alkynylpyridines obtained herein were found to be versatile and convenient intermediates for the preparation of fused-heterocyclic compounds with potential biological and material interests. [ABSTRACT FROM AUTHOR]

Novel and efficient synthesis of 3-acyl-2-naphthols and 3-substituted isocoumarins via the tunable cascade reactions of 2-(4-hydroxy-but-1-ynyl)benzaldehydes have been developed. Treatment of 2-(4-hydroxy-but-1-ynyl)benzaldehydes with 0.7 equiv of Jones reagent in CH3CN and subsequent purification through column chromatography on silica gel pre-eluted with Et3N afforded 3-acyl-2-naphthols with high efficiency. When the same substrates were treated with 3 equiv of Jones reagents in acetone, on the other hand, 3-substituted isocoumarins could be obtained in good yields. [ABSTRACT FROM AUTHOR]