A New, Efficient Method for the Synthesis of Bisindolylmaleimides

Protecting-group-free synthesis of the bisindolylmaleimide GF109203X

“…of n-C 12 H 25 Br for seven hours to give mono-N-alkylation product 17 in an isolated yield of 18%. When the reaction was run at 55 o C for 16 hours using three equivalents of K 2 CO 3 and three equivlanets of bromide, the mono-N-alkylation product (17) was isolated in 73% yield, accompanied by the mono-N'-alkylated product (16) and N,N'-dialkylated product (18) in yields of 7% and 15% respectively. The 1 H-NMR spectrum of 16 recorded in CDCl 3 showed singlets at 8.65 and 7.86 ppm, which were assigned to the NH of indole and maleimide respectively.…”

“…Indole reacted with oxalic chloride followed by quenching the reaction with methanol at 0 o C to give methyl indole-3-glyoxylate 12 in 69% yield, which was previously synthesized by using NaOMe in MeOH at -60 o C. 18 This was reacted with indole-3-acetamide 14 in the presence of t-BuOK, the intermediates was converted into arcyriarubin A in 96% yield by acidic aqueous work-up. Investigation of the reaction of arcyriarubin A (3) with n-C 12 H 25 Br was carried out to see if any mono-N'-substituted product can be obtained.…”

“…The bisindolylmaleimide core was built up via addition of indole-derived Grignard reagent to dibromide 10, 16,17 and the side-chain was introduced by mono-N'-alkylation of 9 (Scheme 1). Later on, Faul et al 18 developed a more efficient synthesis of GF109203X in 51% yield starting from indole, using an O-trityl (Tr) protecting group (Scheme 1). The binsindolylmaleimide core was made via the coupling 19 between 12 and 13, and the side-chain was introduced by Nalkylation of indole-acetamide 14 at an early stage.…”

Friedel-Crafts Reaction of Indoles with Nitroalkenes Catalyzed by Mesoporous Material MCM-41

“…Friedel-Crafts 反应有所报道, 如 CeCl 3 •7H 2 O/NaI 化合 物 [7] , 硫脲及其衍生物 [14,15] , Zn(II), Cu(II)与唑啉络合 物 [6,16,17] , BINOL 的磷酸衍生物 [18] 等. 此外, 本课题组对 吲哚与硝基烯烃的 Friedel-Crafts 反应也做了一些研究 工作, 如 Yb(OTf) 3 催化剂 [19] 、Cu(II)-席夫碱络合物 [20] 、 的苯环上连有 N(CH 3 ) 2 时, 反应产率有所下降(表 3, Entry 9).…”

A New Methodology for Functionalization at the 3-Position of Indoles by a Combination of Boron Lewis Acid with Nitriles

“…[7][8][9][10][11][12][13][14] Especially, the acylation of indoles at the 3-position has been the subject of considerable interest for a long time because their derivatives are key compounds in natural products syntheses and they have important biological activities. [15][16][17][18] However, among these, acylation using nitriles as reagents has been rarely reported. [19][20][21][22] In particular, a combination of B-LA and nitrile has not been reported.…”