Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2024 Feb 29;29(5):1089. doi: 10.3390/molecules29051089

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© 2024 by the authors.

Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

PMC Copyright notice

ESI(+) HPLC-MS analysis of the crude product solution obtained by reaction of precursor 8 with methyl triflate. (A) Calculated m/z values for the different main products and the derived benzothiazol fragments. (B) Total ion current (TIC) chromatogram filtered to m/z 407, which corresponds to tozadenant (t_R = 10.4 min) and its regioisomers (t_R = 7.6 and 11.2 min). (C) TIC filtered to m/z 292, which corresponds to the methylated benzothiazol fragment expected for tozadenant and its N-methylated regioisomer. The peak at 6.5 min (m/z = 421) corresponds to a product formed by double methylation and is therefore not relevant for no-carrier-added ¹¹C-methylation reactions. HPLC conditions: Column: Phenomenex Kinetex® F5, 5 µm, 250 × 4.6 mm; eluent: 25% MeCN in H₂O + 0.2% HCOOH, flow rate: 1.5 mL/min.