A General Synthesis of Tris-Indole Derivatives as Potential Iron Chelators

Abstract

The development of a novel route for the synthesis of a new class of compounds is described. The first tripodal, tris-indole amines are prepared by straightforward routes.

Some electrophilic reactivity studies of di-(2-indolyl)dibenzofurans and di-(2-indolyl)carbazoles

“…2 This aspect of our investigations was not pursued, but reactions with hydrazine were carried out, to see if rather different macrocyclic rings could be constructed. Reaction of dialdehydes 7,9,10 and 12 all gave the corresponding bis-hydrazones 19e22 in high yield, but no dimeric macrocycle formation occurred. However, reaction of the bis-hydrazone 22 with the dialdehyde 12 afforded the 28-membered macrocyclic dimer 23 in 48% yield (Scheme 1).…”

“…After stirring for a further 10 min with cooling the resulting precipitate was filtered, yielding the title compound 24 (0.76 g, 56%) as a yellow powder, mp 196e198 C; IR (KBr): n max 3626,3396,3051,1595,1475,1453,1398,1340,1305,1241,1123,1023,822,785,745 11.94 (2H, s, indole NH); : d 100. 9,111.5,112.4,119.2,119.4,119.7,119.8,120.2,120.7,121.1,122.5,128.8 (aryl CH),105.8,124.0,128.5,129.0,133.0,135.6,136.4,136.9 (aryl C) 4.20. 3,6- (25) The bis-biindolyl compound 25 was synthesized according to the method for compound 24 using 2-indolylcarbazole 3 (1.10 g, 2.70 mmol) and indolin-2-one (0.73 g, 5.40 mmol) in phosphoryl chloride (5 mL) to yield the title compound 25 (1.00 g, 57%) as a yellow powder, mp 240e242 C; IR (KBr): n max 3396,3053,2961,2924,2852,1606,1455,1399,1260,1096,1025,799,746 : d 100.…”

“…8,9 Amide derivatives, in particular, have been used in crystal engineering due to their susceptibility to form hydrogen bonding. 10e13 The reaction of oxalyl chloride with 3-aryl-4,6-dimethoxyindoles has been shown to generate both 2 0 -and 7 0 -glyoxylic acid chlorides, which could be converted into a wide range of glyoxylic esters and amides: 14 the latter formed networks of complementary intra-and inter-molecular hydrogen bond motifs.…”

Effects of Indole Amides on Lettuce and Onion Germination and Growth

“…1) were synthesized from indole-3-carboxylic acid (2) via its acid chloride (Sears et al, 2005), followed by the reaction of the latter with morpholine and the symmetrical diamines piperazine, ethylenediamine, propyl- enediamine, and butylenediamine (putrescine), respectively. A large excess of the liquid symmetrical diamines was added to the unstable acid chloride with careful control of temperature and a minimal reaction time, to prevent formation of symmetrical diamides.…”

Clay Catalyzed Reactions of Indole and its Methyl Derivatives with α, β-unsaturated Carbonyl Compounds

“…10−13 Trisindolyl amines are reported to be important intermediates for the development of new drugs with potential ironchelating abilities. 14 However, for years, many synthetic methods for the preparation of the biologically important, diindolyl 15−22 and trisindolylalkanes, 23−27 have been reported and most of these procedures either in strong acidic conditions, 28,29 expensive reagents and catalysts involved 30−35 or they were carried out under dry conditions using microwaves 36,37 and ultrasound accelerated methods. 38 Environmentally, Benign chemical processes using less hazardous catalysts has become a primary goal in synthetic organic chemistry.…”