We report a unified strategy for the total syntheses of (-)-psychotriasine and (+)-pestalazine B based on the advanced intermediates of 3α-amino-hexahydropyrrolo[2,3-b]indole. To construct these structural motifs, a cascade reaction involving a BINOL-derived phosphoric anion-paired catalyst for enantioselective or diastereoselective azo-coupling/iminium-cyclizations was developed. The remaining...

The title compound, C23H19NO2S2, was obtained as an unexpected regioisomer from an attempted synthesis of an inter-mediate for a substituent-effect study on ergot alkaloids. This is the first report of a 1H-indole mono-thio-ating at the 2- and 3-positions to give a 3H-indole. In the crystal, the acid H atom is twisted roughly 180° from the typical carb-oxy conformation and forms centrosymmetric...

Indole alkaloids have attracted the attention of synthetic chemists because of their intriguing structural features and remarkable bioactivities. This interest is perhaps best represented by the Vinca alkaloid vinblastine (1; Scheme 1), isolated from Catharanthus roseus, which is currently among the foremost drugs used to combat cancer. However, de novo synthesis of novel vinblastine analogues ...

Bioactivity-guided fractionation was used to determine the cytotoxic alkaloids from the toxic plant Peganum harmala. Two novel indole alkaloids, together with ten known ones, were isolated and identified. The novel alkaloids were elucidated to be 2-(indol-3-yl)ethyl-α-L-rhamnopyranosyl-(1 → 6)-β-D-glucopyranoside (2) and 3-hydroxy-3-(N-acetyl-2-aminoethyl)-6-methoxyindol-2-one (3). The cytotoxi...

The cladoniamides are bis-indole alkaloids isolated from Streptomyces uncialis, a lichen-associated actinomycete strain. The cladoniamides have an unusual, indenotryptoline structure rarely observed among bis-indole alkaloids. I report here the isolation, sequencing, and annotation of the cladoniamide biosynthetic gene cluster and compare it to the recently published gene cluster for BE-54017, ...