Preparation of Benthiidine Reddenafil_Kain Industrial Additive

Background and overview^[1]

Benthiidine reddenafil can be used as an intermediate in pharmaceutical synthesis and can also be used to treat precancerous lesions or tumors. It is effective in regulating apoptosis, eliminating and inhibiting precancerous lesions and neoplastic cells. If inhaled, move the patient to fresh air; if in contact with skin, remove contaminated clothing, rinse skin thoroughly with soap and water, seek medical attention if you feel unwell; if in contact with eyes, , you should separate your eyelids, rinse with running water or saline, and seek medical attention immediately; if ingested, rinse your mouth immediately, do not induce vomiting, and seek medical attention immediately.

Preparation^[1]

The specific preparation method of phenthiidine reddenafil is as follows: add piperidine (0.22 ml, 0.0022 mol) to stirred 5-(5-bromoacetyl-2-ethoxyphenyl)-1-methyl -3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidine-7-one (Preparation 8, 0.95 g, 0.0022 mol) and anhydrous potassium carbonate (0.6 g, 0.0044 mol) in acetonitrile (50 ml). After 18 hours, the mixture was evaporated in vacuo, the residue was dissolved in water (50 ml) and the solution was extracted with ethyl acetate (3×30 ml). The organic extracts were combined, washed with brine (3 x 20 ml), dried (Na2SO4) and evaporated in vacuo. The resulting yellow solid was chromatographed on silica gel (12 g) using a gradient of methanol in dichloromethane (0-2% methanol) to give an off-white solid. Crystallization from ethyl acetate-hexane gave the title compound phenthiidine reddenafil as an off-white powder (0.27 g, 28%), m.p. 149-151℃. Actual measured value: C, 66.13; Actual measured value: C. High, 6.90; N, 15.95. C24H31N5O5 requires C, 65.88; measured value: 7.14; N, 16.01%.

Main reference materials

[1] (US6200980) Method of treating a patient having precancerous lesions with phenyl purinone derivatives