(5Z)-5-(5-Chloro-1,2-dihydro-2-oxo-3H-indol-3-ylidene)-4-oxo-2-thioxo-3-thiazolidinepropanoic Acid is used in the preparation of substituted isatinylidenerhodanines. BCL6 inhibitor, an anticancer agent.
ChEBI: FX1 is a member of the class of oxindoles that is 5-chloro-oxindole in which the methylene hydrogens at position 3 have been replaced by an N-(2-carboxyethyl)rhodanin-5-ylidene group. It has a role as an antineoplastic agent. It is a member of oxindoles, an organochlorine compound, a thiazolidinone and a monocarboxylic acid. It is functionally related to a 3-methyleneoxindole and a rhodanine.
FX1 is a BCL6 inhibitor that effectively blocks BCL6 N-terminal BTB domain-mediated corepressors chromosome recruitment (by 61-87%/SMRT and 67-82%/BCOR; 50 μM FX1 for 30 min) and selectively suppresses BCL6-depenent growth (GI50 16-54 μM; >125 μM against BCL6-independent cells) in diffuse large B cell lymphoma (DLBCL) cultures, exhibiting greater affinity than its structure analog 79-6 or BCL6 corepressor SMRT for BTB domain (KD = 7 μM/FX1, 30 μM/SMRT, 129 μM/79-6). FX1 shows greater efficacy than 79-6 in reversing BCL6/corepressors-mediated target genes repression in vitro (IC50 = 35 μM vs. 318 μM with 79-6 by HEK293T-based reporter assay) and in suppressing OCI-Ly7 DLBCL xenograft tumor growth mice in vivo (100% vs. 45% suppression with respective compound via 25 mg/kg/day i.p.).
GENERAL METHOD: Acetic acid (5.0 mL) was added to a mixture of 5-chloroindole-2,3-dione (1.0 mmol), 3-(4-oxo-2-thioxothiazolidin-3-yl)propanoic acid (205 mg, 1.0 mmol) and sodium acetate (820 mg, 10.0 mmol). The reaction mixture was stirred at 105 °C for 30 min to 12 h, followed by cooling to room temperature. Water (15 mL) was added to the reaction system and the resulting mixture was sonicated to form an orange colored slurry. After filtration, the solid portion was washed with deionized water (75 mL) and dried under high vacuum to give the final target product (Z)-3-(5-(5-chloro-2-oxoindolin-3-ylidene)-4-oxo-2-thioxothiazolidin-3-yl)propionic acid as a red fine powder in 71-92% yield.
Spleens in FX1-treating mice are macroscopically indistinguishable from vehicle controls. Total B cell abundance measured by flow cytometry is unaffected by FX1. GC B cells (GL7+FAS+B220+) are significantly depleted by exposure to FX1. Splenic architecture is examined by IHC. Staining with B220 antibody reveals normal B cell follicular structures, whereas staining for the GC B cell-specific marker peanut agglutinin shows profound loss of GCs. The half-life is estimated to be approximately 12 hours. Finally, whether FX1 can induce toxic effects in mice is assessed. No signs of toxicity, inflammation, or infection are evident from H&E-stained sections of lung, gastrointestinal tract, heart, kidney, liver, spleen, and bone marrow of the fixed organs from mice treated with FX1 compare with vehicle[1].
[1] Patent: WO2014/204859, 2014, A2. Location in patent: Page/Page column 34
[2] Tetrahedron Letters, 2013, vol. 54, # 13, p. 1700 - 1703
