Based on recent discoveries concerning the numerous biological properties of thiazolidinones and thiosemicarbazones, new N-substituted heterocyclic derivatives have been designed by combining the indole ring with thioxothiazolidinone, thiazolidinone or thiosemicarbazone. Thus, a series of new thioxothiazolidinone, thiazolidinone, or thiosemicarbazone derivatives bearing indole-based moiety have been designed, synthesized, and developed in good yields.
There are two main molecules in asymmetric unit of the title compound, C27H21N3O6·0.5C2H5OH. In both, the indole ring systems are approximately perpendicular to each other, at dihedral angles of 69.3 (5) and 82.8(4)°. In the crystal, molecules are linked by N—H...O and O—H...O hydrogen bonds into a three-dimensional supramolecular architecture. The solvent ethanol molecule acts as a donor, forming an O—H...O hydrogen bond, reinforcing the structure.
Abstract
Indole diterpenoids constitute a large family of natural products that are characterized by a hybrid molecular architecture consisting of an indole nucleus and diterpenoid moiety. Their pharmacologically and agriculturally important biological properties as well as intriguing molecular architectures have attracted much attention from many synthetic organic chemists. In 2012, we succeeded in the concise total synthesis of a paspalane-type indole diterpenoid, namely paspalinine, by developing a highly efficient indole ring formation protocol. After the report of this total synthesis, 4 research groups achieved the total syntheses of other paspalane- and nodulisporane-type indole diterpenoids using current state-of-the-art methods. This review summarizes the total syntheses of the paspalane- and nodulisporane-type indole diterpenoids that were described in the last 10 years.
AbstractThis introductory chapter describes the various pyrido[1,2-a]indole and azapyrido[1,2-a]indole ring systems that will be covered in subsequent chapters. Biologically active indole alkaloids containing these structural motifs are also detailed, the most well-known of which is the toxic alkaloid strychnine.
Au(I)
complexes catalyze iso-Pictet-Spengler reactions. Ethylamine or methylamine
chains were introduced at C2, C4 or at the nitrogen atom of the indole ring,
and the corresponding substrates were reacted in the presence of aldehydes and
catalytic amounts of Au(I) complexes, leading to a variety of polycyclic
scaffolds. Selectivity could be achieved in the course of a double
iso-Pictet-Spengler reaction involving two successive aldehydes, leading to
highly complex molecules.
Au(I)
complexes catalyze iso-Pictet-Spengler reactions. Ethylamine or methylamine
chains were introduced at C2, C4 or at the nitrogen atom of the indole ring,
and the corresponding substrates were reacted in the presence of aldehydes and
catalytic amounts of Au(I) complexes, leading to a variety of polycyclic
scaffolds. Selectivity could be achieved in the course of a double
iso-Pictet-Spengler reaction involving two successive aldehydes, leading to
highly complex molecules.
Au(I)-Catalyzed Pictet–Spengler Reactions All around the Indole Ring
