SMPT is a non-cleavable (non-degradable) ADC linker that may be utilized to prepare antibody-conjugated active molecules (ADC).

Physicochemical Properties

Molecular Formula	C18H16N2O4S2
Molecular Weight	388.46064
Exact Mass	388.055
CAS #	112241-19-7
PubChem CID	130706
Appearance	Light yellow to yellow solid powder
Density	1.43g/cm3
Boiling Point	547ºC at 760mmHg
Flash Point	284.6ºC
Vapour Pressure	5.11E-12mmHg at 25°C
Index of Refraction	1.675
LogP	3.741
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	7
Rotatable Bond Count	7
Heavy Atom Count	26
Complexity	521
Defined Atom Stereocenter Count	0
InChi Key	GKSPIZSKQWTXQG-UHFFFAOYSA-N
InChi Code	InChI=1S/C18H16N2O4S2/c1-12(25-26-15-4-2-3-11-19-15)13-5-7-14(8-6-13)18(23)24-20-16(21)9-10-17(20)22/h2-8,11-12H,9-10H2,1H3
Chemical Name	(2,5-dioxopyrrolidin-1-yl) 4-[1-(pyridin-2-yldisulfanyl)ethyl]benzoate
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	ADC cytotoxins are connected to antibodies through an ADC connector to form ADCs [1].
References	[1]. Strategies and challenges for the next generation of antibody-drug conjugates. Nat Rev Drug Discov. 2017 May;16(5):315-337.

Solubility Data

Solubility (In Vitro)

DMSO : ~200 mg/mL (~514.85 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 5 mg/mL (12.87 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 50.0 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: ≥ 5 mg/mL (12.87 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 50.0 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	2.5743 mL	12.8713 mL	25.7427 mL
	5 mM	0.5149 mL	2.5743 mL	5.1485 mL
	10 mM	0.2574 mL	1.2871 mL	2.5743 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.