HDAC6-IN-44 (compound H10) is a selective HDAC6 inhibitor with an IC50 value of 8.97 nM. HDAC6-IN-44 can inhibit the phenotype of idiopathic pulmonary fibrosis and has anti-pulmonary fibrosis activity. HDAC6-IN-44 has been shown to inhibit the progression of pulmonary fibrosis in a bleomycin-induced pulmonary fibrosis mouse model and has good metabolic stability. HDAC6-IN-44 is expected to be used in the study of idiopathic pulmonary fibrosis.

Physicochemical Properties

Molecular Formula	C20H21N3O3
Molecular Weight	351.40
Appearance	Typically exists as solids at room temperature
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

Targets	HDAC6 8.97 nM (IC50) HDAC1 878 nM (IC50) HDAC2 3144 nM (IC50) HDAC4 847 nM (IC50) HDAC7 894 nM (IC50) HDAC10 1319 nM (IC50) HDAC11 >5000 nM (IC50)
ln Vitro	HDAC6-IN-44 (compound H10) (2.5-10 μM, 1-300 μM, 48 h) inhibits TGF-β-induced HELF cell proliferation, cell viability and HDAC6 activity in a dose-dependent manner without causing significant cytotoxic effects[1]. HDAC6-IN-44 (2.5-10 μM, 48h) intervenes in the TGF-β1-related fibrotic process by acting on the HDAC6-related signaling pathway[1].
ln Vivo	HDAC6-IN-44 (compound H10) (0.1 mL/10g, intraperitoneal injection, daily injection for three weeks) has a significant inhibitory effect on the increase in HDAC6 activity and collagen deposition in lung tissue in a mouse model of pulmonary fibrosis [1]. HDAC6-IN-44 (0.1 mL/10g, intraperitoneal injection, daily injection for three weeks) can dose-dependently inhibit the progression of pulmonary fibrosis in a mouse model of pulmonary fibrosis [1].
Cell Assay	Cell Viability Assay[1] Cell Types: HELF Tested Concentrations: 2.5-10 μM (cell proliferation test), 1-300 μM (survival toxicity test) Incubation Duration: 48 h Experimental Results: Inhibited TGF-β-induced HELF cell proliferation without significantly inhibiting cell survival at a maximum concentration of approximately 10 μM. Western Blot Analysis[1] Cell Types: HELF Tested Concentrations: 2.5-10 μM Incubation Duration: 48 h Experimental Results: Exhibited dose-dependent increase in acetylated α-tubulin expression and has no effect on histone H3 acetylation, while attenuating the elevated expression of all marker proteins induced by TGF-β1.
Animal Protocol	Animal/Disease Models: Bleomycin-induced pulmonary fibrosis mouse model[1] Doses: 0.1 mL/10g Route of Administration: Intraperitoneal injection (i.p.) , daily for 3 weeks Experimental Results: Caused the blue collagen fiber deposition to be spot-like, with the surrounding alveolar cavity slightly collapsed and the alveolar wall thickened, but the collagen fiber deposition was significantly less than that in the model group. Additionally, HDAC6-IN-44 could dose-dependently inhibit the expression of α-SMA and p-Smad2/3 in BLM-induced pulmonary fibrosis in mice.
References	[1]. Li Y, et al. Discovery of novel pyrrolo[2,1-c][1,4]benzodiazepine-3,11-dione (PBD) derivatives as selective HDAC6 inhibitors for the efficient treatment of idiopathic pulmonary fibrosis (IPF) in vitro and in vivo. Eur J Med Chem. 2024 Jun 17;275:116608.

Solubility Data

Solubility (In Vitro)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Solubility (In Vivo)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples. Injection Formulations (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] *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. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Oral Formulations Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.8458 mL	14.2288 mL	28.4576 mL
	5 mM	0.5692 mL	2.8458 mL	5.6915 mL
	10 mM	0.2846 mL	1.4229 mL	2.8458 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.