GSTO1-IN-1, a chloroacetamide-containing compound, is a novel and potent glutathione S-transferase omega 1 (GSTO1) inhibitor with an IC50 of 31 nM. Glutathione S-transferase omega 1 (GSTO1) is an atypical GST isoform that is overexpressed in several cancers and has been implicated in drug resistance. Currently, no small-molecule drug targeting GSTO1 is under clinical development. Co-crystal structures of GSTO1 with GSTO1-IN-1 demonstrate covalent binding to the active site cysteine. These potent GSTO1 inhibitor GSTO1-IN-1 suppresses cancer cell growth, enhance the cytotoxic effects of cisplatin and inhibit tumour growth in colon cancer models as single agent. Bru-seq-based transcription profiling unravelled novel roles for GSTO1 in cholesterol metabolism, oxidative and endoplasmic stress responses, cytoskeleton and cell migration.These findings demonstrate the therapeutic utility of GSTO1 inhibitors as anticancer agents and identify the novel cellular pathways under GSTO1 regulation in colorectal cancer.

Physicochemical Properties

Molecular Formula	C10H12N2O3SCL2
Molecular Weight	311.18488
Exact Mass	309.994
CAS #	568544-03-6
PubChem CID	3860347
Appearance	Light yellow to yellow solid powder
Density	1.5±0.1 g/cm3
Index of Refraction	1.591
LogP	1.25
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	4
Heavy Atom Count	18
Complexity	394
Defined Atom Stereocenter Count	0
InChi Key	YEHYODCKTNLFQU-UHFFFAOYSA-N
InChi Code	InChI=1S/C10H12Cl2N2O3S/c1-14(2)18(16,17)9-5-7(3-4-8(9)12)13-10(15)6-11/h3-5H,6H2,1-2H3,(H,13,15)
Chemical Name	2-chloro-N-[4-chloro-3-(dimethylsulfamoyl)phenyl]acetamide
Synonyms	GSTO1-IN-2; GSTO1 IN2; GSTO1 IN-2
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

ln Vitro	GSTO1-IN-1 (C1-27) has an IC50 value of 31 nM, which is an effective inhibitor of GSTO1 enzyme activity. When it comes to binding to recombinant proteins and endogenous GSTO1 in a soluble proteomic context, GSTO1-IN-1 also faces competition from 5-chloromethylfluorescein diacetate (CMFDA). A dose-dependent reduction in cell viability was also seen in HCT116 cells treated with GSTO1-IN-1. At submicromolar concentrations, GSTO1-IN-1 prevents HCT116 cell clonal survival [1].
ln Vivo	GSTO1-IN-1's effects were assessed in a human colon cancer cell line xenograft model in order to determine whether it is effective in vivo. HCT116 xenograft-bearing nude mice received a single dose of GSTO1-IN-1 (20–45 mg/kg). Following a 5-week course of treatment, the tumor growth of mice in the GSTO1-IN-1 treatment group was considerably suppressed (P<0.05) in comparison to the vehicle treatment group. Throughout the course of the trial, mice showed no overt toxicity and generally tolerated treatment with GSTO1-IN-1 up to 45 mg/kg with no discernible side effects or changes in average body weight [1].
References	[1]. Mechanistic evaluation and transcriptional signature of a glutathione S-transferase omega 1 inhibitor. Nat Commun. 2016 Oct 5;7:13084.

Solubility Data

Solubility (In Vitro)

DMSO : ≥ 300 mg/mL (~964.07 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (8.03 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: ≥ 2.5 mg/mL (8.03 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Solubility in Formulation 3: ≥ 2.5 mg/mL (8.03 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	3.2136 mL	16.0679 mL	32.1357 mL
	5 mM	0.6427 mL	3.2136 mL	6.4271 mL
	10 mM	0.3214 mL	1.6068 mL	3.2136 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.