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Indolylborates, prepared in situ from 2-bithio-1-methylindol and triethyl borane, form indol-2-yl-ketones by palladium-catalyzed carbonylative cross-coupling reactions. These reactions are fast under carbon monoxide in THF with vinyltriflates at 60 degrees C. All reactions are done in a single vessel. Stereochemistries of the compounds are assigned by NOE studies.

The development of a new atom-economical In[(OTf).sub.3]-catalyzed synthesis of ring-condensed heteroaromatic compounds via a domino intramolecular nucleophilic attack/intermolecular cycloaddition/dehydration reaction is reported. The synthesis used readily available ortho-alkynylanilines and ortho-alkynylbenzaldehydes as starting materials.

Ellipticine, olivacine, and their five reduced natural variants were synthesized via a palladium-catalyzed tandem cyclization/cross-coupling reaction as the key step. In addition, a previously unknown conformer of janetine was obtained through conformational inversion of the D ring in janetine. Because there are few synthetic approaches for reduced natural variants, little is known about the biological activities of these compounds. Six synthetic natural alkaloids and five of their derivatives were evaluated for their antiproliferative activity against HCT-116 and HL-60 cells. The activities of variants with the D-reduced ring or without the C(11)-Me group were lower than those of ellipticine. The conformer of guatambuine showed higher activities than guatambuine. [ABSTRACT FROM AUTHOR]

Concise syntheses of 9-methoxyellipticine, 3,4-dihydroellipticine (µ-alkaloid D), 1,2,3,4-tetrahydroellipticine, 2-methyl-1,2,3,4-tetrahydroellipticine, olivacine, 3,4-dihydroolivacine, (±)-guatambuine, and (±)-janetine were developed starting from hexatriene intermediates readily obtained by Pd-catalyzed tandem cyclization/cross-coupling reaction of indolylborates. The route enables the facile construction of pyrido[4,3- b]carbazoles by Cu-catalyzed 6π-electrocyclization and subsequent transformation of the pyridocarbazole intermediates into pyrido[4,3- b]carbazole alkaloids. [ABSTRACT FROM AUTHOR]

A new approach to form iminoisocoumarins from readily available and stable 2-alkynylbenzamides was developed by using a tandem copper-catalyzed N-arylation and regioselective 6- endo- dig cyclization in the presence of diaryliodonium salts, a copper catalyst, and 2,6-di- tert-butylpyridine. The arylation occurred at the nitrogen atom rather than the oxygen atom of the amide group, the alkynyl carbon, or the benzene ring of the benzamide. Cyclization occurred through a preferential nucleophilic attack by the oxygen rather than the nitrogen atom of the amide group to produce iminoisocoumarin derivatives in good to moderate yields. [ABSTRACT FROM AUTHOR]

Covering: 2012 to 2013. Previous review: Nat. Prod. Rep., 2013, 30, 694–752 This review covers the literature on simple indole alkaloids and those with a nonrearranged monoterpenoid unit from the beginning of 2012 up to the end of 2013, which includes newly isolated alkaloids, structure determinations, total syntheses and biological activities. [ABSTRACT FROM AUTHOR]

( S)-(-)-Dichotomine A and its enantiomer were synthesized from the key intermediate, methyl 1-(1-hydroxyethyl)-β-carboline-3-carboxylate, by enantioselective esterification with Lipase QLM. The first total synthesis of (+)-dichotomide II and its enantiomer were also achieved from ( S)-(-)-dichotomine A methyl ester and its enantiomer. The absolute configuration of the stereogenic center of the reported (+)-dichotomide II was determined to be R. [ABSTRACT FROM AUTHOR]

The palladium-catalyzed tandem cyclization/cross-coupling reaction of triethyl(indol-2-yl)borate with vinyl bromide was successfully used in the concise total synthesis of the indolophenanthridine alkaloids, calothrixins A and B. [ABSTRACT FROM AUTHOR]

Studies the palladium-catalyzed carbonylative cross-coupling reaction with triethyl(1-methylindol-2-yl)borate. Indolylborate intermediate; Transformation of borate; Ketone synthesis.

A new cleavage reaction of carbon–carbon triple bonds proceeds efficiently with NIS and TMSN3, giving the corresponding nitriles in moderate to good yields. [ABSTRACT FROM AUTHOR]

Cu(I)-mediated dimerization of skatoles (I) provides indoloquinazolinones (II). [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "One-Pot Access to 3,3'-Bisindolylmethanes through the Intermolecular Pummerer Reaction" by M. Ishikura and others published in the periodical "Heterocycles" in 2014.

Review: 265 refs. [ABSTRACT FROM AUTHOR]