36070-80-1, In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 36070-80-1 as follows.
In a sealed tube, Intermediate 30 (0.58 g, 1.079 mmol) was dissolved in DMF (5.39 mL). To the resulting solution was added 5-chloropyrazine-2-carboxylic acid (0.188 g, 1.187 mmol), HATU (0.615 g, 1.618 mmol), and pyridine (0.262 mL, 3.24 mmol). The reaction was stirred at 20 C. for 2 hours. The reaction was extracted into ethyl acetate, washed once with water, once with brine, dried with sodium sulfate, filtered through a fritted funnel, and concentrated. The crude material was eluted through a silica gel column using 0-50% EtOAc/Heptane. The desired fractions were combined and concentrated to yield tert-butyl N-[(4aR,6S,11bR)-10-[(5-chloropyrazine-2-carbonyl)amino]-3,3,6,11b-tetramethyl-4,4-dioxo-5,6-dihydro-4-aH-[1]benzoxepino[4,5-b][1,4]thiazin-2-yl]-N-tert-butoxycarbonyl-carbamate (0.640 g, 0.944 mmol, 87% yield) as an off-white solid.
According to the analysis of related databases, 5-Chloropyrazine-2-carboxylic acid, the application of this compound in the production field has become more and more popular.
Reference:
Patent; WHITE, Ryan; ALLEN, Jennifer R.; EPSTEIN, Oleg; HONG, Fang-Tsao; HUA, Zihao; HUMAN, Jason Brooks; LOPEZ, Patricia; OLIVIERI, Philip R.; ROMERO, Karina; SCHENKEL, Laurie; STELLWAGEN, John; TAMAYO, Nuria A.; ZHENG, Xiao Mei; US2014/213581; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem