86919-14-4

Upstream product

• 21320-91-2 2-methoxy-4-nitrobenzene-1-sulfonyl chloride 
• 141-43-5 ethanolamine 

Downstream Products

• 1370451-37-8 1-[2-(2-methoxy-4-nitrophenylsulfonylamino)ethyl]-4,7,10-tris(carboxymethyl)-1,4,7,10-tetraazacyclododecane 
• 1370451-43-6 1-[2-(4-amino-2-methoxyphenylsulfonylamino)ethyl]-4,7,10-tris(carboxymethyl)-1,4,7,10-tetraazacyclododecane 
• 1370451-46-9 C₉H₁₀N₂O₅S 
• 1370451-31-2 2-(2-methoxy-4-nitrophenylsulfonylamino)ethyl methanesulfonate 

Relevant academic research and scientific papers

Development of hypoxia-sensitive Gd3+-based MRI contrast agents

Hypoxia occurs in various diseases, including cancer, ischemia, and acute and chronic vascular diseases. Here we describe the design and synthesis of the first hypoxia-sensitive MRI contrast agents, SAGds. SAGds showed a pH-dependent r1 relaxivity change associated with intramolecular chelation of the nitrogen atom of the sulfonamide moiety to the Gd3+ center. There was a correlation between the pKa of the r1 relaxivity change and the sum of the Hammett σ constants of substituents on the aromatic ring. Among the synthesized compounds, 4NO22MeOSAGd was selectively reduced to the amine by rat liver microsomes under hypoxic conditions, resulting in a 1.8-fold increment of the r1 relaxivity owing to the change in pKa of the arylsulfonamide moiety. This enhancement of the r 1 relaxivity could be clearly detected in T1-weighted MR images. Thus, 4NO22MeOSAGd is a 'smart' MRI contrast agent for the detection of hypoxia under physiological conditions.