The synthesis of 1,2,3-trisubstituted indoles was investigated. More specifically, straightforward synthetic routes towards 1-(1,2-diarylindol-3-yl)-N-PG-THIQs (PG = protecting group, THIQ = tetrahydroisoquinoline) employing transition metal-catalyzed C-H and N-H-bond functionalization were explored. It was found that the synthesis of the target compounds is strongly dependent on the order of e...

This review describes the discovery of new reactions in the field of heterocyclic chemistry. The reactions taken as typical examples involve 1) the photochemical ring transformations of quinolines to indole rings, 2) the ring transformations of indoles to quinazoline and quinoxaline rings, 3) the ring expansion reactions of indoles to 1H-1-benzazepines, 4) the intramolecular photo[2+2]cycloaddi...

The furanobisindole alkaloid, phalarine, possesses a unique structural framework within the alkaloid family of natural products. Our laboratory recently disclosed the racemic total synthesis of phalarine, featuring an efficient azaspiroindolenine rearrangement; this achievement is revisited in detail. Upon completion of the first-generation total synthesis, we explored some interesting mechanis...

A fast and green method is developed for regioselective acylation of indoles in the 3-position without the need for protection of the NH position. The method is based on Friedel-Crafts acylation using acid anhydrides. The method has been optimized, and Y(OTf)₃ in catalytic amounts is found to be the best catalyst together with the commercially available ionic liquid [BMI]BF₄ (1-butyl-3-methylim...

The synthesis of 2-substituted indoles and benzofurans was achieved by nucleophilic aromatic substitution, followed by subsequent 5-endo-dig cyclization between the nucleophile and an ortho acetylene. The acetylene serves the dual role of the electron withdrawing group to activate the substrate for SNAr, and the C1-C2 carbon scaffold for the newly formed 5-membered heteroaromatic ring. This met...

Indoles constitute extensively explored heterocyclic ring systems with wide range of applications in pathophysiological conditions that is, cancer, microbial and viral infections, inflammation, depression, migraine, emesis, hypertension, etc. Presence of indole nucleus in amino acid tryptophan makes it prominent in phytoconstituents such as perfumes, neurotransmitters, auxins (plant hormones), ...

Several indoles served as substrates for the phenoloxidase of Cryptococcus neoformans and resulted in the production of a melanin-like pigment. In general, a higher percentage of C. neoformans var. neoformans (A and D serotypes) isolates could produce pigment from indoles than could those of var. gattii (B and C serotypes). Only compounds with a hydroxyl or an amino group on the phenyl ring pro...

The method described here is based on a brief report by Harley-Mason and Archer. It involves the use of p-dimethylaminocinnamaldehyde (DMACA), a vinylogue of Ehrlich's reagent, as a color reagent for indoles. Colorimetric analyses of indoleacetic acid (IAA) oxidation reaction mixtures were made with the DMACA reagent as a solution rather than a spray. DMACA reagent will yield a wine-red color w...

The effect of melatonin, methoxytryptophol (ML), methoxytryptamine (MT) and parachlorophenylalanine (p-CPA) on the mass and histology of the testes and the adrenal and thyroid glands and on serum thyroid hormone levels have been studied in the recrudescent phase of the feral pigeon Columba livia. All the pineal indoles showed a common anti-gonadal effect, resulting in the arrest of spermatogene...