Crystal structure of tert-butyl (Z)-4-(2-(5-methoxy-3-(2-((methylthio)carbonothioyl)hydrazono)-2-oxoindolin-1-yl)ethyl)piperazine-1-carboxylate, C₂₂H₃₁N₅O₄S₂

Abstract

CCDC no.: 1557526The crystal structure is shown in the figure. Tables 1 and 2 contain details on crystal structure and measurement conditions and a list of the atoms including atomic coordinates and displacement parameters. Source of materialThe title compound was synthesized via a three-step synthetic protocol. The reaction of 5-methoxyindoline-2,3-dione (0.9 g, 5 mmol) with 1,2-dibromoethane (2.8 g,15 mmol) in 15 mL of N,N-dimethylformamide (DMF) in the presence of potassium carbonate (1.0 g, 7.2 mmol) at 40-50°C gave 1-(2-bromoethyl)indoline-2,3-dione [4]. Next, 1-(2-bromoethyl) indoline-2,3-dione (0.6 g, 2.0 mmol) was reacted with tertbutyl piperazine-1-carboxylate (1.1 g, 0.6 mmol) in DMF (5 mL) for 12 h at room temperature to yield 1-((4-(tertbutyloxycarbonyl)piperazin-1-yl)ethyl)-5-methoxyindolin-2,3-dione. Finally, condensation of 1-((4-(tert-butyloxycarbonyl) piperazin-1-yl)-5-methoxyindolin-2,3-dione (0.4 g, 1 mmol) with methyl hydrazinecarbodithioate (0.1 g, 1 mmol) in 5 mL methanol at room temperature for 12 h gave a solid, which was collected by filtration and dried in air. The crude product was purified by recrystallization from methanol (yield 60%; m.p. 421-423 K). Crystals of the title compound were obtained by slow evaporation of the mixed solvent dichloromethane and methanol (5:1, v/v). Experimental detailsH atoms were placed in calculated positions. The U iso values of the hydrogen atoms of methyl groups were set to 1.5U eq (C) and the U iso values of all other hydrogen atoms were set to 1.2U eq (C, N). DiscussionIndolin-2-one derivatives exhibit promising antitumor activity by targeting different biomacromolecules [5,6], of which 3-hydrazinoindolin-2-one derivatives have particularly attracted intensive attention [7,8]. In our previous work, methyl hydrazinecarbodithioate derivatives of 5-fluoro-1-(2-morpholinoethyl)indolin-2-one and 5-methoxy-1-(2-morpholinoethyl)indolin-2-one were used as ligands to achieve two new Pt(II) complexes, which exhibited cytotoxicity against cancer cells by inducing apoptosis [9]. As a continuous work, herein we report a new methyl hydrazinecarbodithioate derivative. X-ray single-crystal diffraction analysis revealed that the hydrazinecarbodithioate and