SPDP-C6-NHS ester is a PROTAC (PROteolysis TArgeting Chimera) linker of the alkyl/ether class, may be utilized to prepare PROTAC protein degraders.

Physicochemical Properties

Molecular Formula	C18H23N3O5S2
Molecular Weight	425.52232
Exact Mass	425.108
CAS #	158913-22-5
PubChem CID	157808
Appearance	White to off-white solid powder
Density	1.36g/cm3
Melting Point	82-84ºC
Index of Refraction	1.61
LogP	2.824
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	8
Rotatable Bond Count	13
Heavy Atom Count	28
Complexity	545
Defined Atom Stereocenter Count	0
SMILES	O=C(ON1C(CCC1=O)=O)CCCCCNC(CCSSC2=NC=CC=C2)=O
InChi Key	QYEAAMBIUQLHFQ-UHFFFAOYSA-N
InChi Code	InChI=1S/C18H23N3O5S2/c22-14(10-13-27-28-15-6-3-5-12-20-15)19-11-4-1-2-7-18(25)26-21-16(23)8-9-17(21)24/h3,5-6,12H,1-2,4,7-11,13H2,(H,19,22)
Chemical Name	(2,5-dioxopyrrolidin-1-yl) 6-[3-(pyridin-2-yldisulfanyl)propanoylamino]hexanoate
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	One ligand is for an E3 ubiquitin ligase, and the other is for the target protein; these two ligands are joined by a linker to form PROTACs. The intracellular ubiquitin-proteasome system is utilized by PROTACs to specifically destroy target proteins[1].
References	[1]. An S, et al. Small-molecule PROTACs: An emerging and promising approach for the development of targeted therapy drugs. EBioMedicine. 2018 Oct;36:553-562

Solubility Data

Solubility (In Vitro)

DMSO : ~50 mg/mL (~117.50 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (5.88 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 (5.88 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 (5.88 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	2.3501 mL	11.7503 mL	23.5007 mL
	5 mM	0.4700 mL	2.3501 mL	4.7001 mL
	10 mM	0.2350 mL	1.1750 mL	2.3501 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.