1. 6-Fluoro-4-oxochroman-2-carboxylic acid
Pei Chen, Shan Qian, Zhe-Qin Shi, Yong Wu Acta Crystallogr Sect E Struct Rep Online. 2010 Jan 9;66(Pt 2):o274. doi: 10.1107/S1600536809054555.
The title compound, C(10)H(7)FO(4), is an inter-mediate in the synthesis of the drug Fidarestat, (2S,4S)-2-aminoformyl-6-fluoro-spiro[chroman-4,4'-imidazolidine]-2',5'-dione. The di-hydro-pyran-one ring adopts an envelope conformation with the asymmetric C atom in the flap position. In the crystal, the mol-ecules are linked into zigzag chains along [100] by O-H⋯O hydrogen bonds and C-H⋯π inter-actions involving the benzene ring.
2. (2S,4S)-3-Acryloyl-6-oxo-2-phenyl-perhydro-pyrimidine-4-carboxylic acid
Sandip K Kundu, Mathew P D Mahindaratne, Brian Quinõnes, George R Negrete, Edward R T Tiekink Acta Crystallogr Sect E Struct Rep Online. 2009 Dec 4;66(Pt 1):o3. doi: 10.1107/S1600536809050892.
In the title compound, C(14)H(14)N(2)O(4), the central six-membered ring adopts a twisted boat conformation with the phenyl substituent occupying an orthogonal position [dihedral angle = 86.88 (11)°]. In the crystal, mol-ecules are linked by carboxylic acid-carbonyl O-H⋯O and amide-carbonyl N-H⋯O hydrogen bonds, forming a three-dimensional network.
3. Optimization of Precursor Synthesis Conditions of (2S,4S)4-[18F]FPArg and Its Application in Glioma Imaging
Yong Huang, Lu Zhang, Meng Wang, Chengze Li, Wei Zheng, Hualong Chen, Ying Liang, Zehui Wu Pharmaceuticals (Basel). 2022 Jul 29;15(8):946. doi: 10.3390/ph15080946.
Although the tracer (2S,4S)4-[18F]FPArg is expected to provide a powerful imaging method for the diagnosis and treatment of clinical tumors, it has not been realized due to the low yield of chemical synthesis and radiolabeling. A simple synthetic method for the radiolabeled precursor of (2S,4S)4-[18F]FPArg in stable yield was obtained by adjusting the sequence of the synthetic steps. Furthermore, the biodistribution experiments confirmed that (2S,4S)4-[18F]FPArg could be cleared out quickly in wild type mouse. Cell uptake experiments and U87MG tumor mouse microPET-CT imaging experiments showed that the tumor had high uptake of (2S,4S)4-[18F]FPArg and the clearance was slow, but (2S,4S)4-[18F]FPArg was rapidly cleared in normal brain tissue. MicroPET-CT imaging of nude mice bearing orthotopic HS683-Luc showed that (2S,4S)4-[18F]FPArg can penetrate blood-brain barrier and image gliomas with a high contrast. Therefore, (2S,4S)4-[18F]FPArg is expected to be further applied in the diagnosis and efficacy evaluation of clinical glioma.
