Pifithrin-β (also known as QB102 and Cyclic-Pifithrin-α) is a novel and potent p53 inhibitor with an IC50 of 23 μM. It is an analog of Pifithrin-α that is cell-permeable but has greater stability and less cytotoxicity. Pifithrin-β has neuroprotective properties by reversing the effects of Alzheimer peptide non-amyloid component in human SH-SY5Y cells. The TP53 gene in humans is responsible for encoding the protein p53. 53 KD is the molecular weight of p53. The p53 gene controls the cell cycle, acting as a tumor suppressor and preventing the development of cancer. Through the activation of DNA repair proteins, cell growth arrest through holding the cell cycle, and induction of apoptosis, the p53 plays a critical role in apoptosis, the inhibition of angiogenesis, and genomic stability. DNA damage, osmotic shock, oxidative stress, and a variety of other stressors can all cause p53 to become activated. By binding to DNA, including p21, activated p53 activates the expression of numerous genes.

Physicochemical Properties

Molecular Formula	C₁₆H₁₆N₂S
Molecular Weight	268.38
Exact Mass	268.103
Elemental Analysis	C, 55.02; H, 4.91; Br, 22.88; N, 8.02; S, 9.18
CAS #	60477-34-1
Related CAS #	Pifithrin-β hydrobromide;511296-88-1
PubChem CID	443278
Appearance	Solid powder
LogP	4.25
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	2
Rotatable Bond Count	1
Heavy Atom Count	19
Complexity	327
Defined Atom Stereocenter Count	0
SMILES	S1C2=NC(C3C([H])=C([H])C(C([H])([H])[H])=C([H])C=3[H])=C([H])N2C2=C1C([H])([H])C([H])([H])C([H])([H])C2([H])[H]
InChi Key	IMUKUMUNZJILCG-UHFFFAOYSA-N
InChi Code	InChI=1S/C16H16N2S/c1-11-6-8-12(9-7-11)13-10-18-14-4-2-3-5-15(14)19-16(18)17-13/h6-10H,2-5H2,1H3
Chemical Name	2-(4-methylphenyl)-5,6,7,8-tetrahydroimidazo[2,1-b][1,3]benzothiazole
Synonyms	Pifithrin-β; PFTβ; Pifithrin-beta; QB102; QB 102; QB-102; PFT-β; Cyclic-Pifithrin-α
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	p53 (IC50 = 23 μM)
ln Vitro	Pifithrin-α, an inhibitor of the p53 protein, is thought to be a promising drug for the treatment of cancer and neurodegenerative diseases. In culture medium, Pifithrin-α is very unstable and quickly transforms into its condensation product, pifithrin-β (PFT), the N-acetyl derivative[2]. Viability testing reveals that pretreatments with 1 and 10 μM pifithrin-β exert neuroprotective effects after 24 hours[3].
References	[1]. Synthesis and biological evaluation of imidazolo[2,1-b]benzothiazole derivatives, as potential p53 inhibitors. Bioorg Med Chem. 2011 Mar 1;19(5):1649-57. [2]. Biological and chemical studies on aryl hydrocarbon receptor induction by the p53 inhibitor pifithrin-α and its condensation product pifithrin-β. Life Sci. 2011 Apr 25;88(17-18):774-83. [3]. p53 functional inhibitors behaving like pifithrin-β counteract the Alzheimer peptide non-β-amyloid component effects in human SH-SY5Y cells. ACS Chem Neurosci. 2014 May 21;5(5):390-9.
Additional Infomation	2-(4-methylphenyl)-5,6,7,8-tetrahydroimidazo[2,1-b][1,3]benzothiazole is a member of imidazoles.

Solubility Data

Solubility (In Vitro)

DMSO: ~10 mM Water: N/A Ethanol: N/A

Solubility (In Vivo)

注意: 如下所列的是一些常用的体内动物实验溶解配方，主要用于溶解难溶或不溶于水的产品（水溶度<1 mg/mL）。 建议您先取少量样品进行尝试，如该配方可行，再根据实验需求增加样品量。 注射用配方 (IP/IV/IM/SC等) 注射用配方1: DMSO : Tween 80： Saline = 10 : 5 : 85 (如： 100 μL DMSO → 50 μL Tween 80 → 850 μL Saline) *生理盐水/Saline的制备：将0.9g氯化钠/NaCl溶解在100 mL ddH ₂ O中，得到澄清溶液。 注射用配方 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (如： 100 μL DMSO → 400 μL PEG300 → 50 μL Tween 80 → 450 μL Saline) 注射用配方 3: DMSO : Corn oil = 10 : 90 (如： 100 μL DMSO → 900 μL Corn oil) 示例: 以注射用配方 3 (DMSO : Corn oil = 10 : 90) 为例说明, 如果要配制 1 mL 2.5 mg/mL的工作液, 您可以取 100 μL 25 mg/mL 澄清的 DMSO 储备液，加到 900 μL Corn oil/玉米油中, 混合均匀。 注射用配方 4: DMSO : 20% SBE-β-CD in Saline = 10 : 90 [如：100 μL DMSO → 900 μL (20% SBE-β-CD in Saline)] *20% SBE-β-CD in Saline的制备（4°C，储存1周）：将2g SBE-β-CD (磺丁基-β-环糊精) 溶解于10mL生理盐水中，得到澄清溶液。 注射用配方 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (如： 500 μL 2-Hydroxypropyl-β-cyclodextrin (羟丙基环胡精)→ 500 μL Saline) 注射用配方 6: DMSO : PEG300 : Castor oil : Saline = 5 : 10 : 20 : 65 (如： 50 μL DMSO → 100 μL PEG300 → 200 μL Castor oil → 650 μL Saline) 注射用配方 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (如： 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) 注射用配方 8: 溶解于Cremophor/Ethanol (50 : 50), 然后用生理盐水稀释。 注射用配方 9: EtOH : Corn oil = 10 : 90 (如： 100 μL EtOH → 900 μL Corn oil) 注射用配方 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (如： 100 μL EtOH → 400 μL PEG300 → 50 μL Tween 80 → 450 μL Saline) 口服配方 口服配方 1: 悬浮于0.5% CMC Na (羧甲基纤维素钠) 口服配方 2: 悬浮于0.5% Carboxymethyl cellulose (羧甲基纤维素) 示例: 以口服配方 1 (悬浮于 0.5% CMC Na)为例说明, 如果要配制 100 mL 2.5 mg/mL 的工作液, 您可以先取0.5g CMC Na并将其溶解于100mL ddH2O中，得到0.5%CMC-Na澄清溶液；然后将250 mg待测化合物加到100 mL前述 0.5%CMC Na溶液中，得到悬浮液。 口服配方 3: 溶解于 PEG400 (聚乙二醇400) 口服配方 4: 悬浮于0.2% Carboxymethyl cellulose (羧甲基纤维素) 口服配方 5: 溶解于0.25% Tween 80 and 0.5% Carboxymethyl cellulose (羧甲基纤维素) 口服配方 6: 做成粉末与食物混合 注意: 以上为较为常见方法，仅供参考， InvivoChem并未独立验证这些配方的准确性。具体溶剂的选择首先应参照文献已报道溶解方法、配方或剂型，对于某些尚未有文献报道溶解方法的化合物，需通过前期实验来确定（建议先取少量样品进行尝试），包括产品的溶解情况、梯度设置、动物的耐受性等。  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	3.7261 mL	18.6303 mL	37.2606 mL
	5 mM	0.7452 mL	3.7261 mL	7.4521 mL
	10 mM	0.3726 mL	1.8630 mL	3.7261 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.