Uses
7-Chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepine-2-thione (cas# 4547-02-8) is a positive allosteric modulator for the muscarinic M1 receptor, which could be a potential treament for the Alzheimer's disease or Schizophrenia.
Synthesis
Under nitrogen protection, 975 g of toluene, 160 g of triethylamine and 204 g (0.92 mol) of phosphorus pentasulfide were added to a dry reaction flask and stirred until the solution was clarified, then 230 g (0.85 mol) of nortrazepam was added. The reaction mixture was heated to 75°C and maintained for 8 hours. After completion of the reaction, it was cooled to room temperature, filtered and dried to obtain light yellow crystals 7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepine-2-thione (M5) 195g in 80% yield and >94% HPLC purity.
The purification step of the crude product M5 obtained from the above preparation: at room temperature, the crude product was dissolved with an equal weight of N,N-dimethylformamide and filtered to remove insoluble matter. Subsequently, water of equal mass with N,N-dimethylformamide was added for recrystallization, and after M5 was completely recrystallized, it was filtered and dried to obtain 175 g of light yellow or nearly yellow crystalline powder, with a purification rate of 90% and an HPLC content of ≥98.5%.
References
[1] Synthesis, 1987, # 2, p. 162 - 164
[2] Collection of Czechoslovak Chemical Communications, 1983, vol. 48, # 1, p. 123-136)
[3] Synthesis, 2004, # 16, p. 2697 - 2703
[4] Bioorganic and Medicinal Chemistry Letters, 2010, vol. 20, # 20, p. 5984 - 5987
[5] Patent: CN104130201, 2016, B. Location in patent: Paragraph 0019; 0025; 0026; 0027; 0028
