Clemastanin B is a lignin that has potent anti-influenza activity by inhibiting viral proliferation, preventing and blocking viral attachment. Clemastanin B targets viral endocytosis, uncoating, or ribonucleoprotein (RNP) export from the nucleus. Clemastanin B has antioxidant and anti-inflammatory activities.

Physicochemical Properties

Molecular Formula	C32H44O16
Molecular Weight	684.68
Exact Mass	684.262
CAS #	112747-98-5
PubChem CID	10009802
Appearance	White to off-white solid powder
Density	1.5±0.1 g/cm3
Boiling Point	922.6±65.0 °C at 760 mmHg
Flash Point	511.8±34.3 °C
Vapour Pressure	0.0±0.3 mmHg at 25°C
Index of Refraction	1.630
LogP	-2.82
Hydrogen Bond Donor Count	9
Hydrogen Bond Acceptor Count	16
Rotatable Bond Count	12
Heavy Atom Count	48
Complexity	978
Defined Atom Stereocenter Count	13
SMILES	COC1=C(C=CC(=C1)C[C@H]2CO[C@@H]([C@H]2CO)C3=CC(=C(C=C3)O[C@H]4[C@@H]([C@H]([C@@H]([C@H](O4)CO)O)O)O)OC)O[C@H]5[C@@H]([C@H]([C@@H]([C@H](O5)CO)O)O)O
InChi Key	PBLWZMSRSJTRHJ-NCIRKIHRSA-N
InChi Code	InChI=1S/C32H44O16/c1-42-20-8-14(3-5-18(20)45-31-28(40)26(38)24(36)22(11-34)47-31)7-16-13-44-30(17(16)10-33)15-4-6-19(21(9-15)43-2)46-32-29(41)27(39)25(37)23(12-35)48-32/h3-6,8-9,16-17,22-41H,7,10-13H2,1-2H3/t16-,17-,22+,23+,24+,25+,26-,27-,28+,29+,30+,31+,32+/m0/s1
Chemical Name	(2R,3S,4S,5R,6S)-2-(hydroxymethyl)-6-[4-[[(3R,4R,5S)-4-(hydroxymethyl)-5-[3-methoxy-4-[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxyphenyl]oxolan-3-yl]methyl]-2-methoxyphenoxy]oxane-3,4,5-triol
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 Note: This product requires protection from light (avoid light exposure) during transportation and storage.
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	Clemastanin B was found to be inactive against respiratory syncytial virus (RSV), adenovirus 3 (ADV3), parainfluenza virus 3 (PIV3), enterovirus 71 (EV71), and human rhinovirus (HRV), but it inhibits several subtypes of human (H1N1, including swine-origin H1N1; H3N2 and influenza B) and avian influenza viruses (H6N2, H7N3, and H9N2) at varying magnitudes of activity (IC50 0.087-0.72 mg/ml). Nucleoprotein (NP) distribution in the nuclei of MDCK cells is caused by clemastanin B treatment (0.05, 0.1, 0.2, and 0.4 mg/ml; for 8 hours)[1]. Progeny virus titer reduction in MDCK cells is markedly inhibited by clemastanin B (48–72 hours) following virus incubation (MOI, 0.01; for 2 hours)[1]. When MDCK cell lines are infected with influenza virus, clemastanin B (pre-incubated for 2 hours) has no protective effect[1].
References	[1]. Antiviral activity of Isatis indigotica root-derived clemastanin B against human and avian influenza A and B viruses in vitro. Int J Mol Med. 2013 Apr;31(4):867-73. [2]. Antiviral activities against influenza virus (FM1) of bioactive fractions and representative compounds extracted from Banlangen (Radix Isatidis). J Tradit Chin Med. 2016 Jun;36(3):369-76. [3]. In vitro antioxidant and anti-inflammatory activities of Radix Isatidis extract and bioaccessibility of six bioactive compounds after simulated gastro-intestinal digestion. J Ethnopharmacol. 2014 Nov 18;157:55-61.
Additional Infomation	Clemastanin B has been reported in Plocama calabrica, Brassica rapa, and other organisms with data available.

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	1.4605 mL	7.3027 mL	14.6054 mL
	5 mM	0.2921 mL	1.4605 mL	2.9211 mL
	10 mM	0.1461 mL	0.7303 mL	1.4605 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.