566169-93-5

Yellow solid

Pittsburgh Compound B (PiB) is a PET tracer for Aβ deposition in Alzheimer's disease (AD), with high affinity and specificity. Through click chemistry modification (introducing a PEG3 linker and an alkyne group at the 6-hydroxy position of Pittsburgh Compound B to generate a clickable Pittsburgh Compound B derivative, followed by covalent conjugation with azide-labeled fluorescent dyes or affinity tags via copper-catalyzed azide-alkyne cycloaddition (CuAAC)), Pittsburgh Compound B and its conjugates can be used for fluorescence imaging, ultrastructural studies, and the enrichment and characterization of Aβ complexes. Pittsburgh Compound B holds great potential in Alzheimer's disease research[1].

BBr3 (1.0 M in CH2Cl2, 10.5 mL, 10.5 mmol) was slowly added dropwise to a solution of 2-[4-(N-monomethyl)aminophenyl]-6-methoxybenzothiazole (44,588 mg, 2.06 mmol) dissolved in dichloromethane (25 mL). The reaction mixture was stirred continuously for 12 hours at room temperature. Upon completion of the reaction, water and aqueous sodium bicarbonate were carefully added to quench the reaction, followed by extraction of the organic phase with dichloromethane. The organic phase was dried over anhydrous sodium sulfate and concentrated under reduced pressure to afford 2-[4-(N-monomethyl)aminophenyl]-6-hydroxybenzothiazole (45,530 mg, 99% yield) as a yellow solid, which did not require further purification. The structure of the product was confirmed by 1H NMR (200 MHz, DMSO-d6) and 13C NMR (100 MHz, DMSO-d6).

[1] Diner I, et al. Generation of Clickable Pittsburgh Compound B for the Detection and Capture of β-Amyloid in Alzheimer's Disease Brain. Bioconjug Chem. 2017 Oct 18;28(10):2627-2637. DOI:10.1021/acs.bioconjchem.7b00500