Application of 83-10-3, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 83-10-3 name is 1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carboxylic acid, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.
EXAMPLE 1 6beta-[D,2-(2,3-dimethyl-1-phenyl-3-pyrazolin-5-one-4-carbonylamino)-2-phenyl]acetamido penicillanic acid, sodium salt 2,3-Dimethyl-1-phenyl-3-pyrazolin-5-one-4-carboxylic acid (0.186 g, 0.8 mmol) in dry dimethyl formamide (D.M.F) (4 ml) was treated with triethylamine (0.12 ml, 0.8 mmol). The solution was cooled to -10 C. and isobutyl chloroformate (0.10 ml, 0.76 mmol) added dropwise. After 1 hour at -10 C., solids were removed by filtration and the solution added to ampicillin (anhydrous) (0.28 g, 0.8 mmol) premixed with triethylamine (0.12 ml, 0.8 mmol) in D.M.F. (10 ml) at -40 C. The solution was allowed to warm to 0 C., stirred for 90 minutes and poured into excess dry ether, with stirring. The precipitate was isolated and partitioned between ethyl acetate and water. The pH was adjusted to 7.5 (bicarbonate addition); the aqueous layer separated and acidified to pH 1.5 (HCl(5N)). Extraction with ethyl acetate, drying (Na2 SO4) and evaporation gave the title product as the free penicillanic acid (0.09 g, 20%), delta((CD3)2 CO) 1.50, 1.58 (2*3H, 2s, (CH3)2), 2.68 (3H, s,=C–CH3), 3.34 (3H, s, –NCH3), 4.36 (1H, s, C3 -proton), 5.53 (1H, d, J 4 Hz, C5 -proton), 5.71 (1H, d of d, J 4, 8 Hz, C6 -proton), 5.94 (1H, d, J 8 Hz, –CHCON–), 7.53 (10H, complex, aryl protons), 8.20 (1H, d, J 8 Hz, –NH–), 9.78 (1H, d, J 8 Hz, –NH–), 6.5-9 (1H, br, –CO2 H).
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carboxylic acid, and friends who are interested can also refer to it.
Reference:
Patent; Beecham Group p.l.c.; US4537886; (1985); A;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics