1H-Indole-5-sulfonamide → HCID 178464642, compound

Participants

Reaction Steps

100 mg (1 mol equiv.) N-Ethyl-2,3-diaza-spiro[4.4]non-3-ene-2-carboximidothioic acid methyl ester and 92.5 mg (1.05 mol equiv.) 1H-indole-5-sulfonic acid amide were added to 3 mL acetonitrile. The reaction mixture was refluxed overnight and volatiles were removed under reduced pressure. The residue was taken up in ethyl acetate and extracted with 2N NaOH. The organic layer was dried over Na2SO4, filtered and evaporated to dryness. Purification by flash chromatography on silica gel (Et2O:EtOAc=1:1) afforded 152 mg (87%) 1H-indole-5-sulfonic acid (2,3-diaza-spiro[4.4]non-3-en-2-yl)-ethylamino-methyleneamide. 1H NMR (400 MHz, CDCl3) δ 1.14 (t, J=7.2 Hz, 3H), 1.59-1.79 (m, 8H), 3.43-3.51 (m, 2H), 3.79 (br.s., 2H), 6.63-6.65 (m, 1H), 6.76 (s, 1H), 6.99 (br.s., 1H), 7.30 (t, J=2.8 Hz, 1H), 7.43 (d, J=8.6 Hz, 1H), 7.76 (dd, J=8.6, 1.8 Hz, 1H), 8.27 (br.s., 1H), 8.54 (br.s., 1H).

Provenance & Evidence